Articles | Volume 12, issue 9
Atmos. Meas. Tech., 12, 4813–4828, 2019
https://doi.org/10.5194/amt-12-4813-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue: Arctic mixed-phase clouds as studied during the ACLOUD/PASCAL...
Atmos. Meas. Tech., 12, 4813–4828, 2019
https://doi.org/10.5194/amt-12-4813-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article 10 Sep 2019
Research article | 10 Sep 2019
peakTree: a framework for structure-preserving radar Doppler spectra analysis
Martin Radenz et al.
Related authors
Ronny Engelmann, Albert Ansmann, Kevin Ohneiser, Hannes Griesche, Martin Radenz, Julian Hofer, Dietrich Althausen, Sandro Dahlke, Marion Maturilli, Igor Veselovskii, Cristofer Jimenez, Robert Wiesen, Holger Baars, Johannes Bühl, Henriette Gebauer, Moritz Haarig, Patric Seifert, Ulla Wandinger, and Andreas Macke
Atmos. Chem. Phys., 21, 13397–13423, https://doi.org/10.5194/acp-21-13397-2021, https://doi.org/10.5194/acp-21-13397-2021, 2021
Short summary
Short summary
A Raman lidar was operated aboard the icebreaker Polarstern during MOSAiC and monitored aerosol and cloud layers in the central Arctic up to 30 km height. The article provides an overview of the spectrum of aerosol profiling observations and shows aerosol–cloud interaction studies for liquid-water and ice clouds. A highlight was the detection of a 10 km deep wildfire smoke layer over the North Pole up to 17 km height from the fire season of 2019, which persisted over the whole winter period.
Moritz Haarig, Albert Ansmann, Ronny Engelmann, Holger Baars, Dietrich Althausen, Carlos Toledano, Benjamin Torres, Martin Radenz, and Ulla Wandinger
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-608, https://doi.org/10.5194/acp-2021-608, 2021
Preprint under review for ACP
Short summary
Short summary
The irregular shape of the dust particles makes it difficult to treat them correctly in optical models. Atmospheric measurements of the dust optical properties are therefore of great importance. The present study increases the space of observed parameters from 355 and 532 nm towards 1064 nm, which is of special importance for the large dust particles. The lidar ratio influenced by mineralogy and the depolarization ratio influenced by shape are measured for the first time at all 3 wavelengths.
Birgit Heese, Athena Augusta Floutsi, Holger Baars, Dietrich Althausen, Julian Hofer, Alina Herzog, Silke Mewes, Martin Radenz, and Yoav Y. Schechner
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-558, https://doi.org/10.5194/acp-2021-558, 2021
Preprint under review for ACP
Short summary
Short summary
The aerosol distribution over Haifa, Israel, was measured for two years by a laser based vertically resolved measurement technique called lidar. From these data, the aerosol types and their percentages of the observed aerosol mixtures were identified in terms of their size and shape. We found mostly desert dust from the surrounding deserts and sea salt from the close by Mediterranean Sea. But, also aerosol from anthropogenic and industrial pollution from local and far away sources were detected.
Hannes J. Griesche, Kevin Ohneiser, Patric Seifert, Martin Radenz, Ronny Engelmann, and Albert Ansmann
Atmos. Chem. Phys., 21, 10357–10374, https://doi.org/10.5194/acp-21-10357-2021, https://doi.org/10.5194/acp-21-10357-2021, 2021
Short summary
Short summary
Heterogeneous ice formation in Arctic mixed-phase clouds under consideration of their surface-coupling state is investigated. Cloud phase and macrophysical properties were determined by means of lidar and cloud radar measurements, the coupling state, and cloud minimum temperature by radiosonde profiles. Above −15 °C cloud minimum temperature, surface-coupled clouds are more likely to contain ice by a factor of 2–6. By means of a literature survey, causes of the observed effects are discussed.
Martin Radenz, Johannes Bühl, Patric Seifert, Holger Baars, Ronny Engelmann, Boris Barja González, Rodanthi-Elisabeth Mamouri, Félix Zamorano, and Albert Ansmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-360, https://doi.org/10.5194/acp-2021-360, 2021
Revised manuscript under review for ACP
Short summary
Short summary
This study brings together long-term ground-based remote sensing observations of mixed-phase clouds at three key locations of aerosol-cloud interactions in the northern and southern hemisphere mid-latitudes. The findings contribute several new aspects on the nature of the excess of supercooled liquid clouds in the southern hemisphere, such as a long-term lidar-based estimate of ice nucleating particle profiles as well as the effects of boundary layer coupling and gravity waves on ice formation.
Fabiola Ramelli, Jan Henneberger, Robert O. David, Johannes Bühl, Martin Radenz, Patric Seifert, Jörg Wieder, Annika Lauber, Julie T. Pasquier, Ronny Engelmann, Claudia Mignani, Maxime Hervo, and Ulrike Lohmann
Atmos. Chem. Phys., 21, 6681–6706, https://doi.org/10.5194/acp-21-6681-2021, https://doi.org/10.5194/acp-21-6681-2021, 2021
Short summary
Short summary
Orographic mixed-phase clouds are an important source of precipitation, but the ice formation processes within them remain uncertain. Here we investigate the origin of ice crystals in a mixed-phase cloud in the Swiss Alps using aerosol and cloud data from in situ and remote sensing observations. We found that ice formation primarily occurs in cloud top generating cells. Our results indicate that secondary ice processes are active in the feeder region, which can enhance orographic precipitation.
Martin Radenz, Patric Seifert, Holger Baars, Athena Augusta Floutsi, Zhenping Yin, and Johannes Bühl
Atmos. Chem. Phys., 21, 3015–3033, https://doi.org/10.5194/acp-21-3015-2021, https://doi.org/10.5194/acp-21-3015-2021, 2021
Kevin Ohneiser, Albert Ansmann, Ronny Engelmann, Christoph Ritter, Alexandra Chudnovsky, Igor Veselovskii, Holger Baars, Henriette Gebauer, Hannes Griesche, Martin Radenz, Julian Hofer, Dietrich Althausen, Sandro Dahlke, and Marion Maturilli
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-117, https://doi.org/10.5194/acp-2021-117, 2021
Revised manuscript accepted for ACP
Short summary
Short summary
The highlight of the lidar measurements during the one-year MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition of the German icebreaker Polarstern (October 2019–October 2020) was the detection of a persistent, 10 km deep Siberian wildfire smoke layer in the upper troposphere and lower stratosphere (UTLS) from about 7–8 km to 17–18 km height that could potentially have impacted the record-breaking ozone depletion over the Arctic in the spring of 2020.
Cristofer Jimenez, Albert Ansmann, Ronny Engelmann, David Donovan, Aleksey Malinka, Patric Seifert, Robert Wiesen, Martin Radenz, Zhenping Yin, Johannes Bühl, Jörg Schmidt, Boris Barja, and Ulla Wandinger
Atmos. Chem. Phys., 20, 15265–15284, https://doi.org/10.5194/acp-20-15265-2020, https://doi.org/10.5194/acp-20-15265-2020, 2020
Short summary
Short summary
Part 2 presents the application of the dual-FOV polarization lidar technique introduced in Part 1. A lidar system was upgraded with a second polarization telescope, and it was deployed at the southernmost tip of South America. A comparison with alternative remote sensing techniques and the evaluation of the aerosol–cloud–wind relation in a convective boundary layer in pristine marine conditions are presented in two case studies, demonstrating the potential of the approach for ACI studies.
Hannes J. Griesche, Patric Seifert, Albert Ansmann, Holger Baars, Carola Barrientos Velasco, Johannes Bühl, Ronny Engelmann, Martin Radenz, Yin Zhenping, and Andreas Macke
Atmos. Meas. Tech., 13, 5335–5358, https://doi.org/10.5194/amt-13-5335-2020, https://doi.org/10.5194/amt-13-5335-2020, 2020
Short summary
Short summary
In summer 2017, the research vessel Polarstern performed cruise PS106 to the Arctic north of Svalbard. In the frame of the cruise, remote-sensing observations of the atmosphere were performed on Polarstern to continuously monitor aerosol and clouds above the vessel. In our study, we present the deployed instrumentation and applied data analysis methods and provide case studies of the aerosol and cloud observations made during the cruise. Statistics of low-cloud occurrence are presented as well.
Kevin Ohneiser, Albert Ansmann, Holger Baars, Patric Seifert, Boris Barja, Cristofer Jimenez, Martin Radenz, Audrey Teisseire, Athina Floutsi, Moritz Haarig, Andreas Foth, Alexandra Chudnovsky, Ronny Engelmann, Félix Zamorano, Johannes Bühl, and Ulla Wandinger
Atmos. Chem. Phys., 20, 8003–8015, https://doi.org/10.5194/acp-20-8003-2020, https://doi.org/10.5194/acp-20-8003-2020, 2020
Short summary
Short summary
Unique lidar observations of a strong perturbation in stratospheric aerosol conditions in the Southern Hemisphere caused by the extreme Australian bushfires in 2019–2020 are presented. One of the main goals of this article is to provide the CALIPSO and Aeolus spaceborne lidar science teams with basic input parameters (lidar ratios, depolarization ratios) for a trustworthy documentation of this record-breaking event.
Athena Augusta Floutsi, Holger Baars, Martin Radenz, Moritz Haarig, Zhenping Yin, Patric Seifert, Cristofer Jimenez, Ulla Wandinger, Ronny Engelmann, Boris Barja, Felix Zamorano, and Albert Ansmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-453, https://doi.org/10.5194/acp-2020-453, 2020
Preprint withdrawn
Diego Villanueva, Bernd Heinold, Patric Seifert, Hartwig Deneke, Martin Radenz, and Ina Tegen
Atmos. Chem. Phys., 20, 2177–2199, https://doi.org/10.5194/acp-20-2177-2020, https://doi.org/10.5194/acp-20-2177-2020, 2020
Short summary
Short summary
Spaceborne retrievals of cloud phase were analysed together with an atmospheric composition model to assess the global frequency of ice and liquid clouds. This analysis showed that at equal temperature the average occurrence of ice clouds increases for higher dust mixing ratios on a day-to-day basis in the middle and high latitudes. This indicates that mineral dust may have a strong impact on the occurrence of ice clouds even in remote areas.
Johannes Bühl, Patric Seifert, Martin Radenz, Holger Baars, and Albert Ansmann
Atmos. Meas. Tech., 12, 6601–6617, https://doi.org/10.5194/amt-12-6601-2019, https://doi.org/10.5194/amt-12-6601-2019, 2019
Short summary
Short summary
In the present paper, we present a novel remote-sensing technique for the measurement of ice crystal number concentrations in clouds. The fall velocity of ice crystals measured with values from cloud radar and a radar wind profiler is used in order to derive information about ice crystal size and number concentration. In contrast to existing methods based on the combination of lidar and cloud radar, the present method can also be used in optically thick clouds.
Zhenping Yin, Albert Ansmann, Holger Baars, Patric Seifert, Ronny Engelmann, Martin Radenz, Cristofer Jimenez, Alina Herzog, Kevin Ohneiser, Karsten Hanbuch, Luc Blarel, Philippe Goloub, Gaël Dubois, Stephane Victori, and Fabrice Maupin
Atmos. Meas. Tech., 12, 5685–5698, https://doi.org/10.5194/amt-12-5685-2019, https://doi.org/10.5194/amt-12-5685-2019, 2019
Short summary
Short summary
A new shipborne Sun–sky–lunar photometer was validated through comparisons with collocated MICROTOPS II and multiwavelength Raman polarization lidar measurements during two trans-Atlantic cruises. A full diurnal cycle of mixed dust–smoke episode was captured by both the shipborne photometer and lidar. The coefficient of determination for the linear regression between MICROTOPS II and the shipborne photometer was 0.993 for AOD at 500 nm based on the entire dataset.
Andreas Foth, Thomas Kanitz, Ronny Engelmann, Holger Baars, Martin Radenz, Patric Seifert, Boris Barja, Michael Fromm, Heike Kalesse, and Albert Ansmann
Atmos. Chem. Phys., 19, 6217–6233, https://doi.org/10.5194/acp-19-6217-2019, https://doi.org/10.5194/acp-19-6217-2019, 2019
Short summary
Short summary
In this study, we present the vertical aerosol distribution in the pristine region of the southern tip of South America determined by ground-based and spaceborne lidar observations. Most aerosol load is contained within the planetary boundary layer up to about 1200 m. The free troposphere is characterized by a very low aerosol concentration but a frequent occurrence of clouds. Lofted aerosol layers were rarely observed and, when present, were characterized by very low optical thicknesses.
Diego Villanueva, Bernd Heinold, Patric Seifert, Hartwig Deneke, Martin Radenz, and Ina Tegen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-1074, https://doi.org/10.5194/acp-2018-1074, 2018
Revised manuscript not accepted
Short summary
Short summary
Two different satellite products were analysed together with an atmospheric composition model to assess the global frequency of ice and liquid stratiform clouds. This analysis showed that at equal temperature the average occurrence of fully glaciated stratiform clouds was found to increase for higher dust mixing-ratios on a day-to-day basis in the mid- and high latitudes. This indicates that mineral dust may have a strong impact in the occurrence of ice clouds even in remote areas.
Martin Radenz, Johannes Bühl, Volker Lehmann, Ulrich Görsdorf, and Ronny Leinweber
Atmos. Meas. Tech., 11, 5925–5940, https://doi.org/10.5194/amt-11-5925-2018, https://doi.org/10.5194/amt-11-5925-2018, 2018
Short summary
Short summary
Ultra-high-frequency radar wind profilers are widely used for remote sensing of horizontal and vertical wind velocity. They emit electromagnetic radiation at a wavelength of 60 cm and receive signals from both falling particles and the air itself. In this paper, we describe a method to separate both signal components with the help of an additional cloud radar system in order to come up with undisturbed measurements of both vertical air velocity and the fall velocity of particles.
Stephanie Bohlmann, Holger Baars, Martin Radenz, Ronny Engelmann, and Andreas Macke
Atmos. Chem. Phys., 18, 9661–9679, https://doi.org/10.5194/acp-18-9661-2018, https://doi.org/10.5194/acp-18-9661-2018, 2018
Short summary
Short summary
Lidar measurements of two expeditions across the Atlantic Ocean aboard the research vessel Polarstern are presented. In addition to Saharan dust layers and complex dust–smoke mixtures, pure marine conditions with enhanced particle depolarisation ratios on top of the marine boundary layer could be observed. A statistical analysis shows latitudinal differences in the optical properties within the marine boundary layer and illustrates the potential of these properties for aerosol classification.
Moritz Haarig, Albert Ansmann, Josef Gasteiger, Konrad Kandler, Dietrich Althausen, Holger Baars, Martin Radenz, and David A. Farrell
Atmos. Chem. Phys., 17, 14199–14217, https://doi.org/10.5194/acp-17-14199-2017, https://doi.org/10.5194/acp-17-14199-2017, 2017
Short summary
Short summary
The depolarization ratio and the backscatter coefficient of marine particles are correlated with the relative humidity. The measurements were performed under atmospheric conditions with a multi-wavelength lidar system in pure marine conditions over Barbados in February 2014. For RH < 50 % the sea salt particles have a cubic-like shape resulting in an enhanced depolarization ratio of up to 0.15. This agrees with model results of cubic sea salt. The extinction enhancement f(RH) factor was derived.
Ronny Engelmann, Albert Ansmann, Kevin Ohneiser, Hannes Griesche, Martin Radenz, Julian Hofer, Dietrich Althausen, Sandro Dahlke, Marion Maturilli, Igor Veselovskii, Cristofer Jimenez, Robert Wiesen, Holger Baars, Johannes Bühl, Henriette Gebauer, Moritz Haarig, Patric Seifert, Ulla Wandinger, and Andreas Macke
Atmos. Chem. Phys., 21, 13397–13423, https://doi.org/10.5194/acp-21-13397-2021, https://doi.org/10.5194/acp-21-13397-2021, 2021
Short summary
Short summary
A Raman lidar was operated aboard the icebreaker Polarstern during MOSAiC and monitored aerosol and cloud layers in the central Arctic up to 30 km height. The article provides an overview of the spectrum of aerosol profiling observations and shows aerosol–cloud interaction studies for liquid-water and ice clouds. A highlight was the detection of a 10 km deep wildfire smoke layer over the North Pole up to 17 km height from the fire season of 2019, which persisted over the whole winter period.
Philipp Richter, Mathias Palm, Christine Weinzierl, Hannes Griesche, Penny M. Rowe, and Justus Notholt
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2021-284, https://doi.org/10.5194/essd-2021-284, 2021
Preprint under review for ESSD
Short summary
Short summary
We present a dataset of cloud optical depths, effective radii and water paths from optically thin clouds observed in the Arctic around Svalbard. The data has been retrieved from infrared spectral radiance measured using a FTIR spectrometer. Besides a description of the measurements and retrieval technique, the data is set into context with results of corresponding measurements from microwave radiometer, lidar and cloud radar.
Carmen Córdoba-Jabonero, Albert Ansmann, Cristofer Jiménez, Holger Baars, María-Ángeles López-Cayuela, and Ronny Engelmann
Atmos. Meas. Tech., 14, 5225–5239, https://doi.org/10.5194/amt-14-5225-2021, https://doi.org/10.5194/amt-14-5225-2021, 2021
Short summary
Short summary
An experimental assessment of a polarized micro-pulse lidar (P-MPL) in comparison to reference lidars is presented regarding the retrieval of aerosol optical properties. The evaluation is focused on both the optimally determined overlap function and volume linear depolarization ratio. A P-MPL overlap must be regularly estimated to derive suitable aerosol products (backscatter, extinction, and particle depolarization ratio). This methodology can be easily applied to other P-MPL systems.
Moritz Haarig, Albert Ansmann, Ronny Engelmann, Holger Baars, Dietrich Althausen, Carlos Toledano, Benjamin Torres, Martin Radenz, and Ulla Wandinger
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-608, https://doi.org/10.5194/acp-2021-608, 2021
Preprint under review for ACP
Short summary
Short summary
The irregular shape of the dust particles makes it difficult to treat them correctly in optical models. Atmospheric measurements of the dust optical properties are therefore of great importance. The present study increases the space of observed parameters from 355 and 532 nm towards 1064 nm, which is of special importance for the large dust particles. The lidar ratio influenced by mineralogy and the depolarization ratio influenced by shape are measured for the first time at all 3 wavelengths.
Birgit Heese, Athena Augusta Floutsi, Holger Baars, Dietrich Althausen, Julian Hofer, Alina Herzog, Silke Mewes, Martin Radenz, and Yoav Y. Schechner
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-558, https://doi.org/10.5194/acp-2021-558, 2021
Preprint under review for ACP
Short summary
Short summary
The aerosol distribution over Haifa, Israel, was measured for two years by a laser based vertically resolved measurement technique called lidar. From these data, the aerosol types and their percentages of the observed aerosol mixtures were identified in terms of their size and shape. We found mostly desert dust from the surrounding deserts and sea salt from the close by Mediterranean Sea. But, also aerosol from anthropogenic and industrial pollution from local and far away sources were detected.
Hannes J. Griesche, Kevin Ohneiser, Patric Seifert, Martin Radenz, Ronny Engelmann, and Albert Ansmann
Atmos. Chem. Phys., 21, 10357–10374, https://doi.org/10.5194/acp-21-10357-2021, https://doi.org/10.5194/acp-21-10357-2021, 2021
Short summary
Short summary
Heterogeneous ice formation in Arctic mixed-phase clouds under consideration of their surface-coupling state is investigated. Cloud phase and macrophysical properties were determined by means of lidar and cloud radar measurements, the coupling state, and cloud minimum temperature by radiosonde profiles. Above −15 °C cloud minimum temperature, surface-coupled clouds are more likely to contain ice by a factor of 2–6. By means of a literature survey, causes of the observed effects are discussed.
Albert Ansmann, Kevin Ohneiser, Rodanthi-Elisavet Mamouri, Daniel A. Knopf, Igor Veselovskii, Holger Baars, Ronny Engelmann, Andreas Foth, Cristofer Jimenez, Patric Seifert, and Boris Barja
Atmos. Chem. Phys., 21, 9779–9807, https://doi.org/10.5194/acp-21-9779-2021, https://doi.org/10.5194/acp-21-9779-2021, 2021
Short summary
Short summary
We present retrievals of tropospheric and stratospheric height profiles of particle mass, volume, surface area concentration of wildfire smoke layers, and related cloud condensation nuclei (CCN) and ice-nucleating particle (INP) concentrations. The new analysis scheme is applied to ground-based lidar observations of stratospheric Australian smoke over southern South America and to spaceborne lidar observations of tropospheric North American smoke.
Jerónimo Escribano, Enza Di Tomaso, Oriol Jorba, Martina Klose, Maria Gonçalves Ageitos, Francesca Macchia, Vassilis Amiridis, Holger Baars, Eleni Marinou, Emmanouil Proestakis, Claudia Urbanneck, Dietrich Althausen, Johannes Bühl, Rodanthi-Elisavet Mamouri, and Carlos Pérez García-Pando
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-442, https://doi.org/10.5194/acp-2021-442, 2021
Preprint under review for ACP
Short summary
Short summary
We explore the benefits and consistency in adding lidar dust observations in a dust optical depth assimilation. We show that adding lidar data to an dust optical depth assimilation has valuable benefits and the dust analyses improves. We discuss the impact of the narrow satellite footprint of the lidar dust observations in the assimilation.
Heike Kalesse-Los, Willi Schimmel, Edward Luke, and Patric Seifert
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-60, https://doi.org/10.5194/amt-2021-60, 2021
Preprint under review for AMT
Short summary
Short summary
It is important to detect the vertical distribution of cloud droplets and ice in mixed-phase clouds. Here, an artificial neural network previously developed for Arctic clouds is applied to a mid-latitudinal cloud radar data set. The performance of this technique is contrasted to the Cloudnet target classification. For thick/multi-layer clouds, the machine-learning technique is better at detecting liquid, but in convective clouds where lidar data is available, Cloudnet performs better.
Silke Trömel, Clemens Simmer, Ulrich Blahak, Armin Blanke, Florian Ewald, Michael Frech, Mathias Gergely, Martin Hagen, Sabine Hörnig, Tijana Janjic, Heike Kalesse, Stefan Kneifel, Christoph Knote, Jana Mendrok, Manuel Moser, Gregor Möller, Kai Mühlbauer, Alexander Myagkov, Velibor Pejcic, Patric Seifert, Prabhakar Shrestha, Audrey Teisseire, Leoni von Terzi, Eleni Tetoni, Teresa Vogl, Christiane Voigt, Yuefei Zeng, Tobias Zinner, and Johannes Quaas
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-346, https://doi.org/10.5194/acp-2021-346, 2021
Revised manuscript accepted for ACP
Short summary
Short summary
The article introduces the ACP readership to ongoing research in Germany on cloud and precipitation related process information inherent in polarimetric radar measurements, outlines pathways to inform atmospheric models with radar-based information and points to remaining challenges towards an improved fusion of radar polarimetry and atmospheric modelling.
Martin Radenz, Johannes Bühl, Patric Seifert, Holger Baars, Ronny Engelmann, Boris Barja González, Rodanthi-Elisabeth Mamouri, Félix Zamorano, and Albert Ansmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-360, https://doi.org/10.5194/acp-2021-360, 2021
Revised manuscript under review for ACP
Short summary
Short summary
This study brings together long-term ground-based remote sensing observations of mixed-phase clouds at three key locations of aerosol-cloud interactions in the northern and southern hemisphere mid-latitudes. The findings contribute several new aspects on the nature of the excess of supercooled liquid clouds in the southern hemisphere, such as a long-term lidar-based estimate of ice nucleating particle profiles as well as the effects of boundary layer coupling and gravity waves on ice formation.
Fabiola Ramelli, Jan Henneberger, Robert O. David, Johannes Bühl, Martin Radenz, Patric Seifert, Jörg Wieder, Annika Lauber, Julie T. Pasquier, Ronny Engelmann, Claudia Mignani, Maxime Hervo, and Ulrike Lohmann
Atmos. Chem. Phys., 21, 6681–6706, https://doi.org/10.5194/acp-21-6681-2021, https://doi.org/10.5194/acp-21-6681-2021, 2021
Short summary
Short summary
Orographic mixed-phase clouds are an important source of precipitation, but the ice formation processes within them remain uncertain. Here we investigate the origin of ice crystals in a mixed-phase cloud in the Swiss Alps using aerosol and cloud data from in situ and remote sensing observations. We found that ice formation primarily occurs in cloud top generating cells. Our results indicate that secondary ice processes are active in the feeder region, which can enhance orographic precipitation.
Ulrike Egerer, André Ehrlich, Matthias Gottschalk, Hannes Griesche, Roel A. J. Neggers, Holger Siebert, and Manfred Wendisch
Atmos. Chem. Phys., 21, 6347–6364, https://doi.org/10.5194/acp-21-6347-2021, https://doi.org/10.5194/acp-21-6347-2021, 2021
Short summary
Short summary
This paper describes a case study of a three-day period with a persistent humidity inversion above a mixed-phase cloud layer in the Arctic. It is based on measurements with a tethered balloon, complemented with results from a dedicated high-resolution large-eddy simulation. Both methods show that the humidity layer acts to provide moisture to the cloud layer through downward turbulent transport. This supply of additional moisture can contribute to the persistence of Arctic clouds.
Ville Vakkari, Holger Baars, Stephanie Bohlmann, Johannes Bühl, Mika Komppula, Rodanthi-Elisavet Mamouri, and Ewan James O'Connor
Atmos. Chem. Phys., 21, 5807–5820, https://doi.org/10.5194/acp-21-5807-2021, https://doi.org/10.5194/acp-21-5807-2021, 2021
Short summary
Short summary
The depolarization ratio is a valuable parameter for aerosol categorization from remote sensing measurements. Here, we introduce particle depolarization ratio measurements at the 1565 nm wavelength, which is substantially longer than previously utilized wavelengths and enhances our capabilities to study the wavelength dependency of the particle depolarization ratio.
Fabiola Ramelli, Jan Henneberger, Robert O. David, Annika Lauber, Julie T. Pasquier, Jörg Wieder, Johannes Bühl, Patric Seifert, Ronny Engelmann, Maxime Hervo, and Ulrike Lohmann
Atmos. Chem. Phys., 21, 5151–5172, https://doi.org/10.5194/acp-21-5151-2021, https://doi.org/10.5194/acp-21-5151-2021, 2021
Short summary
Short summary
Interactions between dynamics, microphysics and orography can enhance precipitation. Yet the exact role of these interactions is still uncertain. Here we investigate the role of low-level blocking and turbulence for precipitation by combining remote sensing and in situ observations. The observations show that blocked flow can induce the formation of feeder clouds and that turbulence can enhance hydrometeor growth, demonstrating the importance of local flow effects for orographic precipitation.
Martin Radenz, Patric Seifert, Holger Baars, Athena Augusta Floutsi, Zhenping Yin, and Johannes Bühl
Atmos. Chem. Phys., 21, 3015–3033, https://doi.org/10.5194/acp-21-3015-2021, https://doi.org/10.5194/acp-21-3015-2021, 2021
Kevin Ohneiser, Albert Ansmann, Ronny Engelmann, Christoph Ritter, Alexandra Chudnovsky, Igor Veselovskii, Holger Baars, Henriette Gebauer, Hannes Griesche, Martin Radenz, Julian Hofer, Dietrich Althausen, Sandro Dahlke, and Marion Maturilli
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-117, https://doi.org/10.5194/acp-2021-117, 2021
Revised manuscript accepted for ACP
Short summary
Short summary
The highlight of the lidar measurements during the one-year MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition of the German icebreaker Polarstern (October 2019–October 2020) was the detection of a persistent, 10 km deep Siberian wildfire smoke layer in the upper troposphere and lower stratosphere (UTLS) from about 7–8 km to 17–18 km height that could potentially have impacted the record-breaking ozone depletion over the Arctic in the spring of 2020.
Cristofer Jimenez, Albert Ansmann, Ronny Engelmann, David Donovan, Aleksey Malinka, Jörg Schmidt, Patric Seifert, and Ulla Wandinger
Atmos. Chem. Phys., 20, 15247–15263, https://doi.org/10.5194/acp-20-15247-2020, https://doi.org/10.5194/acp-20-15247-2020, 2020
Short summary
Short summary
A novel lidar method to study cloud microphysical properties (of liquid water clouds) and to study aerosol–cloud interaction (ACI) is developed and presented in this paper. In Part 1, the theoretical framework including an error analysis is given together with an overview of the aerosol information that the same lidar system can obtain. The ACI concept based on aerosol and cloud information is also explained. Applications of the proposed approach to lidar measurements are presented in Part 2.
Cristofer Jimenez, Albert Ansmann, Ronny Engelmann, David Donovan, Aleksey Malinka, Patric Seifert, Robert Wiesen, Martin Radenz, Zhenping Yin, Johannes Bühl, Jörg Schmidt, Boris Barja, and Ulla Wandinger
Atmos. Chem. Phys., 20, 15265–15284, https://doi.org/10.5194/acp-20-15265-2020, https://doi.org/10.5194/acp-20-15265-2020, 2020
Short summary
Short summary
Part 2 presents the application of the dual-FOV polarization lidar technique introduced in Part 1. A lidar system was upgraded with a second polarization telescope, and it was deployed at the southernmost tip of South America. A comparison with alternative remote sensing techniques and the evaluation of the aerosol–cloud–wind relation in a convective boundary layer in pristine marine conditions are presented in two case studies, demonstrating the potential of the approach for ACI studies.
Martin Bauch, Thomas Labbé, Annabell Engel, and Patric Seifert
Clim. Past, 16, 2343–2358, https://doi.org/10.5194/cp-16-2343-2020, https://doi.org/10.5194/cp-16-2343-2020, 2020
Short summary
Short summary
The onset of Little Ice Age cooling around 1310 CE was preceded in Europe by a series of droughts in the first decade of the 14th century that were uniquely severe in the period 1200–1400. Based mainly on information from chronicles and other historical texts, we reconstructed the socioeconomic and cultural impact of these events but also a seesaw pattern of multiannual droughts in the Mediterranean and Europe north of the Alps that has remarkable resemblances to the 2018–2019 dry period.
Holger Baars, Alina Herzog, Birgit Heese, Kevin Ohneiser, Karsten Hanbuch, Julian Hofer, Zhenping Yin, Ronny Engelmann, and Ulla Wandinger
Atmos. Meas. Tech., 13, 6007–6024, https://doi.org/10.5194/amt-13-6007-2020, https://doi.org/10.5194/amt-13-6007-2020, 2020
Short summary
Short summary
A first validation for the European satellite Aeolus is presented. Aeolus is the first satellite that can actively measure horizontal wind profiles from space.
Radiosonde launches on board the German research vessel Polarstern have been utilized to validate Aeolus observations over the Atlantic Ocean, a region where almost no other reference measurements are available. It is shown that Aeolus is able to measure accurately atmospheric winds and thus may significantly improve weather forecasts.
Hannes J. Griesche, Patric Seifert, Albert Ansmann, Holger Baars, Carola Barrientos Velasco, Johannes Bühl, Ronny Engelmann, Martin Radenz, Yin Zhenping, and Andreas Macke
Atmos. Meas. Tech., 13, 5335–5358, https://doi.org/10.5194/amt-13-5335-2020, https://doi.org/10.5194/amt-13-5335-2020, 2020
Short summary
Short summary
In summer 2017, the research vessel Polarstern performed cruise PS106 to the Arctic north of Svalbard. In the frame of the cruise, remote-sensing observations of the atmosphere were performed on Polarstern to continuously monitor aerosol and clouds above the vessel. In our study, we present the deployed instrumentation and applied data analysis methods and provide case studies of the aerosol and cloud observations made during the cruise. Statistics of low-cloud occurrence are presented as well.
Julian Hofer, Albert Ansmann, Dietrich Althausen, Ronny Engelmann, Holger Baars, Khanneh Wadinga Fomba, Ulla Wandinger, Sabur F. Abdullaev, and Abduvosit N. Makhmudov
Atmos. Chem. Phys., 20, 9265–9280, https://doi.org/10.5194/acp-20-9265-2020, https://doi.org/10.5194/acp-20-9265-2020, 2020
Short summary
Short summary
For the first time, a dense data set of particle extinction-to-backscatter ratios (lidar ratios), depolarization ratios, and backscatter- and extinction-related Ångström exponents for a Central Asian site are presented. The observations were performed with a continuously running multiwavelength polarization Raman lidar at Dushanbe, Tajikistan, during an 18-month campaign. The found optical properties reflect the large range of occurring aerosol mixtures.
Maria Filioglou, Elina Giannakaki, John Backman, Jutta Kesti, Anne Hirsikko, Ronny Engelmann, Ewan O'Connor, Jari T. T. Leskinen, Xiaoxia Shang, Hannele Korhonen, Heikki Lihavainen, Sami Romakkaniemi, and Mika Komppula
Atmos. Chem. Phys., 20, 8909–8922, https://doi.org/10.5194/acp-20-8909-2020, https://doi.org/10.5194/acp-20-8909-2020, 2020
Short summary
Short summary
Dust optical properties are region-dependent. Saharan, Asian, and Arabian dusts do not pose similar optical properties in terms of lidar ratios; thus, a universal lidar ratio for dust particles will lead to biases. The present study analyses observations over the United Arab Emirates, quantifying the optical and geometrical extents of the aerosol layers in the area, providing at the same time the Arabian dust properties along with chemical analysis of dust samples collected in the region.
Philipp Richter, Mathias Palm, Christine Weinzierl, Hannes Griesche, Penny M. Rowe, and Justus Notholt
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-266, https://doi.org/10.5194/amt-2020-266, 2020
Preprint withdrawn
Short summary
Short summary
Optically thin clouds containing low amounts of water are difficult to observe, but due to their frequent presence they have a non-neglectible impact on Earth's radiative budget. Here we present a retrieval for mixed-phase clouds from thermal-infared spectra, measured using a FTIR spectrometer. Even in situations where the atmospheric windows in the far-infrared are not applicable, cloud optical depths, effective droplet radii and water paths of mixed-phase clouds can be retrieved.
Kevin Ohneiser, Albert Ansmann, Holger Baars, Patric Seifert, Boris Barja, Cristofer Jimenez, Martin Radenz, Audrey Teisseire, Athina Floutsi, Moritz Haarig, Andreas Foth, Alexandra Chudnovsky, Ronny Engelmann, Félix Zamorano, Johannes Bühl, and Ulla Wandinger
Atmos. Chem. Phys., 20, 8003–8015, https://doi.org/10.5194/acp-20-8003-2020, https://doi.org/10.5194/acp-20-8003-2020, 2020
Short summary
Short summary
Unique lidar observations of a strong perturbation in stratospheric aerosol conditions in the Southern Hemisphere caused by the extreme Australian bushfires in 2019–2020 are presented. One of the main goals of this article is to provide the CALIPSO and Aeolus spaceborne lidar science teams with basic input parameters (lidar ratios, depolarization ratios) for a trustworthy documentation of this record-breaking event.
Athena Augusta Floutsi, Holger Baars, Martin Radenz, Moritz Haarig, Zhenping Yin, Patric Seifert, Cristofer Jimenez, Ulla Wandinger, Ronny Engelmann, Boris Barja, Felix Zamorano, and Albert Ansmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-453, https://doi.org/10.5194/acp-2020-453, 2020
Preprint withdrawn
Montserrat Costa-Surós, Odran Sourdeval, Claudia Acquistapace, Holger Baars, Cintia Carbajal Henken, Christa Genz, Jonas Hesemann, Cristofer Jimenez, Marcel König, Jan Kretzschmar, Nils Madenach, Catrin I. Meyer, Roland Schrödner, Patric Seifert, Fabian Senf, Matthias Brueck, Guido Cioni, Jan Frederik Engels, Kerstin Fieg, Ksenia Gorges, Rieke Heinze, Pavan Kumar Siligam, Ulrike Burkhardt, Susanne Crewell, Corinna Hoose, Axel Seifert, Ina Tegen, and Johannes Quaas
Atmos. Chem. Phys., 20, 5657–5678, https://doi.org/10.5194/acp-20-5657-2020, https://doi.org/10.5194/acp-20-5657-2020, 2020
Short summary
Short summary
The impact of anthropogenic aerosols on clouds is a key uncertainty in climate change. This study analyses large-domain simulations with a new high-resolution model to investigate the differences in clouds between 1985 and 2013 comparing multiple observational datasets. The differences in aerosol and in cloud droplet concentrations are clearly detectable. For other quantities, the detection and attribution proved difficult, despite a substantial impact on the Earth's energy budget.
Julian Hofer, Albert Ansmann, Dietrich Althausen, Ronny Engelmann, Holger Baars, Sabur F. Abdullaev, and Abduvosit N. Makhmudov
Atmos. Chem. Phys., 20, 4695–4711, https://doi.org/10.5194/acp-20-4695-2020, https://doi.org/10.5194/acp-20-4695-2020, 2020
Short summary
Short summary
For the first time, continuous, vertically resolved long-term aerosol measurements were conducted with a state-of-the-art multiwavelength lidar over a Central Asian site. Such observations are urgently required in efforts to predict future climate and environmental conditions and to support spaceborne remote sensing (ground truth activities).
Carola Barrientos Velasco, Hartwig Deneke, Hannes Griesche, Patric Seifert, Ronny Engelmann, and Andreas Macke
Atmos. Meas. Tech., 13, 1757–1775, https://doi.org/10.5194/amt-13-1757-2020, https://doi.org/10.5194/amt-13-1757-2020, 2020
Short summary
Short summary
In the changing Arctic, quantifying the resulting variability of incoming solar radiation is important to better elucidate the net radiative effect of clouds. As part of a multidisciplinary expedition in the central Arctic held in early summer 2017, a novel network of pyranometers was deployed over an ice floe to investigate the spatiotemporal variability of solar radiation under different sky conditions. This study presents the collected data and an analysis of the spatiotemporal variability.
Sabine Griessbach, Lars Hoffmann, Reinhold Spang, Peggy Achtert, Marc von Hobe, Nina Mateshvili, Rolf Müller, Martin Riese, Christian Rolf, Patric Seifert, and Jean-Paul Vernier
Atmos. Meas. Tech., 13, 1243–1271, https://doi.org/10.5194/amt-13-1243-2020, https://doi.org/10.5194/amt-13-1243-2020, 2020
Short summary
Short summary
In this paper we study the cloud top height derived from MIPAS measurements. Previous studies showed contradictory results with respect to MIPAS, both underestimating and overestimating cloud top height. We used simulations and found that overestimation and/or underestimation depend on cloud extinction. To support our findings we compared MIPAS cloud top heights of volcanic sulfate aerosol with measurements from CALIOP, ground-based lidar, and ground-based twilight measurements.
Diego Villanueva, Bernd Heinold, Patric Seifert, Hartwig Deneke, Martin Radenz, and Ina Tegen
Atmos. Chem. Phys., 20, 2177–2199, https://doi.org/10.5194/acp-20-2177-2020, https://doi.org/10.5194/acp-20-2177-2020, 2020
Short summary
Short summary
Spaceborne retrievals of cloud phase were analysed together with an atmospheric composition model to assess the global frequency of ice and liquid clouds. This analysis showed that at equal temperature the average occurrence of ice clouds increases for higher dust mixing ratios on a day-to-day basis in the middle and high latitudes. This indicates that mineral dust may have a strong impact on the occurrence of ice clouds even in remote areas.
Johannes Bühl, Patric Seifert, Martin Radenz, Holger Baars, and Albert Ansmann
Atmos. Meas. Tech., 12, 6601–6617, https://doi.org/10.5194/amt-12-6601-2019, https://doi.org/10.5194/amt-12-6601-2019, 2019
Short summary
Short summary
In the present paper, we present a novel remote-sensing technique for the measurement of ice crystal number concentrations in clouds. The fall velocity of ice crystals measured with values from cloud radar and a radar wind profiler is used in order to derive information about ice crystal size and number concentration. In contrast to existing methods based on the combination of lidar and cloud radar, the present method can also be used in optically thick clouds.
Albert Ansmann, Rodanthi-Elisavet Mamouri, Johannes Bühl, Patric Seifert, Ronny Engelmann, Julian Hofer, Argyro Nisantzi, James D. Atkinson, Zamin A. Kanji, Berko Sierau, Mihalis Vrekoussis, and Jean Sciare
Atmos. Chem. Phys., 19, 15087–15115, https://doi.org/10.5194/acp-19-15087-2019, https://doi.org/10.5194/acp-19-15087-2019, 2019
Short summary
Short summary
For the first time, a closure study of the relationship between the ice-nucleating particle concentration (INPC) and ice crystal number concentration (ICNC) in altocumulus and cirrus layers, solely based on ground-based active remote sensing, is presented. The closure studies were conducted in Cyprus. A focus was on altocumulus and cirrus layers which developed in pronounced Saharan dust layers. The closure studies show that heterogeneous ice nucleation can play a dominant role in ice formation.
Holger Baars, Albert Ansmann, Kevin Ohneiser, Moritz Haarig, Ronny Engelmann, Dietrich Althausen, Ingrid Hanssen, Michael Gausa, Aleksander Pietruczuk, Artur Szkop, Iwona S. Stachlewska, Dongxiang Wang, Jens Reichardt, Annett Skupin, Ina Mattis, Thomas Trickl, Hannes Vogelmann, Francisco Navas-Guzmán, Alexander Haefele, Karen Acheson, Albert A. Ruth, Boyan Tatarov, Detlef Müller, Qiaoyun Hu, Thierry Podvin, Philippe Goloub, Igor Veselovskii, Christophe Pietras, Martial Haeffelin, Patrick Fréville, Michaël Sicard, Adolfo Comerón, Alfonso Javier Fernández García, Francisco Molero Menéndez, Carmen Córdoba-Jabonero, Juan Luis Guerrero-Rascado, Lucas Alados-Arboledas, Daniele Bortoli, Maria João Costa, Davide Dionisi, Gian Luigi Liberti, Xuan Wang, Alessia Sannino, Nikolaos Papagiannopoulos, Antonella Boselli, Lucia Mona, Giuseppe D'Amico, Salvatore Romano, Maria Rita Perrone, Livio Belegante, Doina Nicolae, Ivan Grigorov, Anna Gialitaki, Vassilis Amiridis, Ourania Soupiona, Alexandros Papayannis, Rodanthi-Elisaveth Mamouri, Argyro Nisantzi, Birgit Heese, Julian Hofer, Yoav Y. Schechner, Ulla Wandinger, and Gelsomina Pappalardo
Atmos. Chem. Phys., 19, 15183–15198, https://doi.org/10.5194/acp-19-15183-2019, https://doi.org/10.5194/acp-19-15183-2019, 2019
Zhenping Yin, Albert Ansmann, Holger Baars, Patric Seifert, Ronny Engelmann, Martin Radenz, Cristofer Jimenez, Alina Herzog, Kevin Ohneiser, Karsten Hanbuch, Luc Blarel, Philippe Goloub, Gaël Dubois, Stephane Victori, and Fabrice Maupin
Atmos. Meas. Tech., 12, 5685–5698, https://doi.org/10.5194/amt-12-5685-2019, https://doi.org/10.5194/amt-12-5685-2019, 2019
Short summary
Short summary
A new shipborne Sun–sky–lunar photometer was validated through comparisons with collocated MICROTOPS II and multiwavelength Raman polarization lidar measurements during two trans-Atlantic cruises. A full diurnal cycle of mixed dust–smoke episode was captured by both the shipborne photometer and lidar. The coefficient of determination for the linear regression between MICROTOPS II and the shipborne photometer was 0.993 for AOD at 500 nm based on the entire dataset.
Eleni Marinou, Matthias Tesche, Athanasios Nenes, Albert Ansmann, Jann Schrod, Dimitra Mamali, Alexandra Tsekeri, Michael Pikridas, Holger Baars, Ronny Engelmann, Kalliopi-Artemis Voudouri, Stavros Solomos, Jean Sciare, Silke Groß, Florian Ewald, and Vassilis Amiridis
Atmos. Chem. Phys., 19, 11315–11342, https://doi.org/10.5194/acp-19-11315-2019, https://doi.org/10.5194/acp-19-11315-2019, 2019
Short summary
Short summary
We assess the feasibility of ground-based and spaceborne lidars to retrieve profiles of cloud-relevant aerosol concentrations and ice-nucleating particles. The retrieved profiles are in good agreement with airborne in situ measurements. Our methodology will be applied to satellite observations in the future so as to provide a global 3D product of cloud-relevant properties.
Andreas Foth, Thomas Kanitz, Ronny Engelmann, Holger Baars, Martin Radenz, Patric Seifert, Boris Barja, Michael Fromm, Heike Kalesse, and Albert Ansmann
Atmos. Chem. Phys., 19, 6217–6233, https://doi.org/10.5194/acp-19-6217-2019, https://doi.org/10.5194/acp-19-6217-2019, 2019
Short summary
Short summary
In this study, we present the vertical aerosol distribution in the pristine region of the southern tip of South America determined by ground-based and spaceborne lidar observations. Most aerosol load is contained within the planetary boundary layer up to about 1200 m. The free troposphere is characterized by a very low aerosol concentration but a frequent occurrence of clouds. Lofted aerosol layers were rarely observed and, when present, were characterized by very low optical thicknesses.
Cristofer Jimenez, Albert Ansmann, Ronny Engelmann, Moritz Haarig, Jörg Schmidt, and Ulla Wandinger
Atmos. Meas. Tech., 12, 1077–1093, https://doi.org/10.5194/amt-12-1077-2019, https://doi.org/10.5194/amt-12-1077-2019, 2019
Short summary
Short summary
We propose an extended formalism for a full instrumental characterization of a three-channel lidar system, allowing the retrieval of highly accurate linear depolarization profiles. The results obtained at several depolarizing scenarios, the good agreement with the retrievals of a second collocated calibrated lidar system, and the long-term stability of the calibration parameters corroborate the potential and robustness of the new technique.
Michael Weger, Bernd Heinold, Christa Engler, Ulrich Schumann, Axel Seifert, Romy Fößig, Christiane Voigt, Holger Baars, Ulrich Blahak, Stephan Borrmann, Corinna Hoose, Stefan Kaufmann, Martina Krämer, Patric Seifert, Fabian Senf, Johannes Schneider, and Ina Tegen
Atmos. Chem. Phys., 18, 17545–17572, https://doi.org/10.5194/acp-18-17545-2018, https://doi.org/10.5194/acp-18-17545-2018, 2018
Short summary
Short summary
The impact of desert dust on cloud formation is investigated for a major Saharan dust event over Europe by interactive regional dust modeling. Dust particles are very efficient ice-nucleating particles promoting the formation of ice crystals in clouds. The simulations show that the observed extensive cirrus development was likely related to the above-average dust load. The interactive dust–cloud feedback in the model significantly improves the agreement with aircraft and satellite observations.
Diego Villanueva, Bernd Heinold, Patric Seifert, Hartwig Deneke, Martin Radenz, and Ina Tegen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-1074, https://doi.org/10.5194/acp-2018-1074, 2018
Revised manuscript not accepted
Short summary
Short summary
Two different satellite products were analysed together with an atmospheric composition model to assess the global frequency of ice and liquid stratiform clouds. This analysis showed that at equal temperature the average occurrence of fully glaciated stratiform clouds was found to increase for higher dust mixing-ratios on a day-to-day basis in the mid- and high latitudes. This indicates that mineral dust may have a strong impact in the occurrence of ice clouds even in remote areas.
Martin Radenz, Johannes Bühl, Volker Lehmann, Ulrich Görsdorf, and Ronny Leinweber
Atmos. Meas. Tech., 11, 5925–5940, https://doi.org/10.5194/amt-11-5925-2018, https://doi.org/10.5194/amt-11-5925-2018, 2018
Short summary
Short summary
Ultra-high-frequency radar wind profilers are widely used for remote sensing of horizontal and vertical wind velocity. They emit electromagnetic radiation at a wavelength of 60 cm and receive signals from both falling particles and the air itself. In this paper, we describe a method to separate both signal components with the help of an additional cloud radar system in order to come up with undisturbed measurements of both vertical air velocity and the fall velocity of particles.
Albert Ansmann, Holger Baars, Alexandra Chudnovsky, Ina Mattis, Igor Veselovskii, Moritz Haarig, Patric Seifert, Ronny Engelmann, and Ulla Wandinger
Atmos. Chem. Phys., 18, 11831–11845, https://doi.org/10.5194/acp-18-11831-2018, https://doi.org/10.5194/acp-18-11831-2018, 2018
Short summary
Short summary
Extremely large light extinction coefficients of 500 Mm-1, about 20 times higher than after the Pinatubo volcanic eruptions in 1991, were observed by EARLINET lidars in the stratosphere over central Europe from 21 to 22 August, 2017. This paper provides an overview based on ground-based (lidar, AERONET) and satellite (MODIS, OMI) remote sensing.
Moritz Haarig, Albert Ansmann, Holger Baars, Cristofer Jimenez, Igor Veselovskii, Ronny Engelmann, and Dietrich Althausen
Atmos. Chem. Phys., 18, 11847–11861, https://doi.org/10.5194/acp-18-11847-2018, https://doi.org/10.5194/acp-18-11847-2018, 2018
Short summary
Short summary
The worldwide only triple-wavelength polarization/Raman lidar was used to measure optical, microphysical, and morphological properties of aged Canadian wildfire smoke occurring in the troposphere and stratosphere over Leipzig, Germany, in August 2017. A strong contrast between the tropospheric and stratospheric smoke properties was found.
Stephanie Bohlmann, Holger Baars, Martin Radenz, Ronny Engelmann, and Andreas Macke
Atmos. Chem. Phys., 18, 9661–9679, https://doi.org/10.5194/acp-18-9661-2018, https://doi.org/10.5194/acp-18-9661-2018, 2018
Short summary
Short summary
Lidar measurements of two expeditions across the Atlantic Ocean aboard the research vessel Polarstern are presented. In addition to Saharan dust layers and complex dust–smoke mixtures, pure marine conditions with enhanced particle depolarisation ratios on top of the marine boundary layer could be observed. A statistical analysis shows latitudinal differences in the optical properties within the marine boundary layer and illustrates the potential of these properties for aerosol classification.
Dimitra Mamali, Eleni Marinou, Jean Sciare, Michael Pikridas, Panagiotis Kokkalis, Michael Kottas, Ioannis Binietoglou, Alexandra Tsekeri, Christos Keleshis, Ronny Engelmann, Holger Baars, Albert Ansmann, Vassilis Amiridis, Herman Russchenberg, and George Biskos
Atmos. Meas. Tech., 11, 2897–2910, https://doi.org/10.5194/amt-11-2897-2018, https://doi.org/10.5194/amt-11-2897-2018, 2018
Short summary
Short summary
The paper's scope is to evaluate the performance of in situ atmospheric aerosol instrumentation on board unmanned aerial vehicles (UAVs) and the performance of algorithms used to calculate the aerosol mass from remote sensing instruments by comparing the two independent techniques to each other. Our results indicate that UAV-based aerosol measurements (using specific in situ and remote sensing instrumentation) can provide reliable ways to determine the aerosol mass throughout the atmosphere.
Guangyao Dai, Dietrich Althausen, Julian Hofer, Ronny Engelmann, Patric Seifert, Johannes Bühl, Rodanthi-Elisavet Mamouri, Songhua Wu, and Albert Ansmann
Atmos. Meas. Tech., 11, 2735–2748, https://doi.org/10.5194/amt-11-2735-2018, https://doi.org/10.5194/amt-11-2735-2018, 2018
Short summary
Short summary
The presented calibration method grants access to quality approved automated atmospheric water vapor profiles from lidar measurements. This method uses the Raman lidar data from the water vapor and nitrogen channels and additional data from sun photometer and GDAS. The retrieved water vapor profiles agree well with respective profiles from radio soundings. The paper describes this method and shows results from the CyCARE (Cyprus Cloud Aerosol and Rain Experiment) campaign in 2015–2017.
Livio Belegante, Juan Antonio Bravo-Aranda, Volker Freudenthaler, Doina Nicolae, Anca Nemuc, Dragos Ene, Lucas Alados-Arboledas, Aldo Amodeo, Gelsomina Pappalardo, Giuseppe D'Amico, Francesco Amato, Ronny Engelmann, Holger Baars, Ulla Wandinger, Alexandros Papayannis, Panos Kokkalis, and Sérgio N. Pereira
Atmos. Meas. Tech., 11, 1119–1141, https://doi.org/10.5194/amt-11-1119-2018, https://doi.org/10.5194/amt-11-1119-2018, 2018
Short summary
Short summary
This paper presents different depolarization calibration procedures used to improve the quality of the depolarization data. The results illustrate a significant improvement of the depolarization lidar products for all the selected EARLINET lidar instruments. The calibrated volume and particle depolarization profiles at 532 nm show values that fall within a range that is accepted in the literature. The depolarization accuracy estimate at 532 nm is better than ±0.03 for all cases.
Sebastian Düsing, Birgit Wehner, Patric Seifert, Albert Ansmann, Holger Baars, Florian Ditas, Silvia Henning, Nan Ma, Laurent Poulain, Holger Siebert, Alfred Wiedensohler, and Andreas Macke
Atmos. Chem. Phys., 18, 1263–1290, https://doi.org/10.5194/acp-18-1263-2018, https://doi.org/10.5194/acp-18-1263-2018, 2018
Alexandra Tsekeri, Anton Lopatin, Vassilis Amiridis, Eleni Marinou, Julia Igloffstein, Nikolaos Siomos, Stavros Solomos, Panagiotis Kokkalis, Ronny Engelmann, Holger Baars, Myrto Gratsea, Panagiotis I. Raptis, Ioannis Binietoglou, Nikolaos Mihalopoulos, Nikolaos Kalivitis, Giorgos Kouvarakis, Nikolaos Bartsotas, George Kallos, Sara Basart, Dirk Schuettemeyer, Ulla Wandinger, Albert Ansmann, Anatoli P. Chaikovsky, and Oleg Dubovik
Atmos. Meas. Tech., 10, 4995–5016, https://doi.org/10.5194/amt-10-4995-2017, https://doi.org/10.5194/amt-10-4995-2017, 2017
Short summary
Short summary
The Generalized Aerosol Retrieval from Radiometer and Lidar Combined data algorithm (GARRLiC) and the LIdar-Radiometer Inversion Code (LIRIC) provide the opportunity to study the aerosol vertical distribution by combining ground-based lidar and sun-photometric measurements. Here, we utilize the capabilities of both algorithms for the characterization of Saharan dust and marine particles, along with their mixtures, in the south-eastern Mediterranean.
Albert Ansmann, Franziska Rittmeister, Ronny Engelmann, Sara Basart, Oriol Jorba, Christos Spyrou, Samuel Remy, Annett Skupin, Holger Baars, Patric Seifert, Fabian Senf, and Thomas Kanitz
Atmos. Chem. Phys., 17, 14987–15006, https://doi.org/10.5194/acp-17-14987-2017, https://doi.org/10.5194/acp-17-14987-2017, 2017
Julian Hofer, Dietrich Althausen, Sabur F. Abdullaev, Abduvosit N. Makhmudov, Bakhron I. Nazarov, Georg Schettler, Ronny Engelmann, Holger Baars, K. Wadinga Fomba, Konrad Müller, Bernd Heinold, Konrad Kandler, and Albert Ansmann
Atmos. Chem. Phys., 17, 14559–14577, https://doi.org/10.5194/acp-17-14559-2017, https://doi.org/10.5194/acp-17-14559-2017, 2017
Short summary
Short summary
The Central Asian Dust Experiment provides unprecedented data on vertically resolved aerosol optical properties over Central Asia from continuous 18-month polarization Raman lidar observations in Dushanbe, Tajikistan. Central Asia is affected by climate change (e.g. glacier retreat) but in a large part missing vertically resolved aerosol measurements, which would help to better understand transport of dust and pollution aerosol across Central Asia and their influence on climate and health.
Moritz Haarig, Albert Ansmann, Josef Gasteiger, Konrad Kandler, Dietrich Althausen, Holger Baars, Martin Radenz, and David A. Farrell
Atmos. Chem. Phys., 17, 14199–14217, https://doi.org/10.5194/acp-17-14199-2017, https://doi.org/10.5194/acp-17-14199-2017, 2017
Short summary
Short summary
The depolarization ratio and the backscatter coefficient of marine particles are correlated with the relative humidity. The measurements were performed under atmospheric conditions with a multi-wavelength lidar system in pure marine conditions over Barbados in February 2014. For RH < 50 % the sea salt particles have a cubic-like shape resulting in an enhanced depolarization ratio of up to 0.15. This agrees with model results of cubic sea salt. The extinction enhancement f(RH) factor was derived.
Franziska Rittmeister, Albert Ansmann, Ronny Engelmann, Annett Skupin, Holger Baars, Thomas Kanitz, and Stefan Kinne
Atmos. Chem. Phys., 17, 12963–12983, https://doi.org/10.5194/acp-17-12963-2017, https://doi.org/10.5194/acp-17-12963-2017, 2017
Moritz Haarig, Albert Ansmann, Dietrich Althausen, André Klepel, Silke Groß, Volker Freudenthaler, Carlos Toledano, Rodanthi-Elisavet Mamouri, David A. Farrell, Damien A. Prescod, Eleni Marinou, Sharon P. Burton, Josef Gasteiger, Ronny Engelmann, and Holger Baars
Atmos. Chem. Phys., 17, 10767–10794, https://doi.org/10.5194/acp-17-10767-2017, https://doi.org/10.5194/acp-17-10767-2017, 2017
Short summary
Short summary
Our measurements performed with a lidar on Barbados give a vertical profile of Saharan dust, which was transported over 5000 km across the Atlantic. The new triple-wavelength depolarization technique reveals more information about the shape and size of dust, which will improve our understanding of the aging process of dust in the atmosphere and its representation in dust models. Changing properties of dust particles influence the solar radiation and the cloud properties and thus our climate.
Holger Baars, Patric Seifert, Ronny Engelmann, and Ulla Wandinger
Atmos. Meas. Tech., 10, 3175–3201, https://doi.org/10.5194/amt-10-3175-2017, https://doi.org/10.5194/amt-10-3175-2017, 2017
Short summary
Short summary
A novel technique for multiwavelength lidars is introduced to derive information on the particle type in the tropospheric profile in analogy to the Cloudnet target classification. Four different aerosol classes and several cloud classes are defined. The technique is based on absolute calibrated lidar signals in temporally high resolution and thus is also well suited for aerosol–cloud-interaction studies. The approach was applied on a 2-month data set of the HOPE campaign in western Germany.
Johannes Bühl, Patric Seifert, Ronny Engelmann, Julia Fruntke, and Albert Ansmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-230, https://doi.org/10.5194/acp-2017-230, 2017
Revised manuscript not accepted
Short summary
Short summary
Vertical air motion is a key driver of physical processes in clouds. The stability of clouds and the process of ice formation have been shown to depend critically on vertical air motions. However, observations of vertical air motions and ice formation in clouds are rare. This motivated us in the Up- and downdraft in Drop and Ice Nucleation Experiment (UDINE) to deliver a comprehensive statistics, connecting remote-sensing observations of vertical motions and ice formation.
Andreas Macke, Patric Seifert, Holger Baars, Christian Barthlott, Christoph Beekmans, Andreas Behrendt, Birger Bohn, Matthias Brueck, Johannes Bühl, Susanne Crewell, Thomas Damian, Hartwig Deneke, Sebastian Düsing, Andreas Foth, Paolo Di Girolamo, Eva Hammann, Rieke Heinze, Anne Hirsikko, John Kalisch, Norbert Kalthoff, Stefan Kinne, Martin Kohler, Ulrich Löhnert, Bomidi Lakshmi Madhavan, Vera Maurer, Shravan Kumar Muppa, Jan Schween, Ilya Serikov, Holger Siebert, Clemens Simmer, Florian Späth, Sandra Steinke, Katja Träumner, Silke Trömel, Birgit Wehner, Andreas Wieser, Volker Wulfmeyer, and Xinxin Xie
Atmos. Chem. Phys., 17, 4887–4914, https://doi.org/10.5194/acp-17-4887-2017, https://doi.org/10.5194/acp-17-4887-2017, 2017
Short summary
Short summary
This article provides an overview of the instrumental setup and the main results obtained during the two HD(CP)2 Observational Prototype Experiments HOPE-Jülich and HOPE-Melpitz conducted in Germany in April–May and Sept 2013, respectively. Goal of the field experiments was to provide high-resolution observational datasets for both, improving the understaning of boundary layer and cloud processes, as well as for the evaluation of the new ICON model that is run at 156 m horizontal resolution.
Diego A. Gouveia, Boris Barja, Henrique M. J. Barbosa, Patric Seifert, Holger Baars, Theotonio Pauliquevis, and Paulo Artaxo
Atmos. Chem. Phys., 17, 3619–3636, https://doi.org/10.5194/acp-17-3619-2017, https://doi.org/10.5194/acp-17-3619-2017, 2017
Short summary
Short summary
We derive the first comprehensive statistics of cirrus clouds over a tropical rain forest. Monthly frequency of occurrence can be as high as 88 %. The diurnal cycle follows that of precipitation, and frequently cirrus is found in the tropopause layer. The mean values of cloud top, base, thickness, optical depth and lidar ratio were 14.3 km, 12.9 km, 1.4 km, 0.25, and 23 sr respectively. The high fraction (42 %) of subvisible clouds may contaminate satellite measurements to an unknown extent.
Juan Antonio Bravo-Aranda, Livio Belegante, Volker Freudenthaler, Lucas Alados-Arboledas, Doina Nicolae, María José Granados-Muñoz, Juan Luis Guerrero-Rascado, Aldo Amodeo, Giusseppe D'Amico, Ronny Engelmann, Gelsomina Pappalardo, Panos Kokkalis, Rodanthy Mamouri, Alex Papayannis, Francisco Navas-Guzmán, Francisco José Olmo, Ulla Wandinger, Francesco Amato, and Martial Haeffelin
Atmos. Meas. Tech., 9, 4935–4953, https://doi.org/10.5194/amt-9-4935-2016, https://doi.org/10.5194/amt-9-4935-2016, 2016
Short summary
Short summary
This work analyses the lidar polarizing sensitivity by means of the Stokes–Müller formalism and provides a new tool to quantify the systematic error of the volume linear depolarization ration (δ) using the Monte Carlo technique. Results evidence the importance of the lidar polarizing effects which can lead to systematic errors larger than 100 %. Additionally, we demonstrate that a proper lidar characterization helps to reduce the uncertainty.
Moritz Haarig, Ronny Engelmann, Albert Ansmann, Igor Veselovskii, David N. Whiteman, and Dietrich Althausen
Atmos. Meas. Tech., 9, 4269–4278, https://doi.org/10.5194/amt-9-4269-2016, https://doi.org/10.5194/amt-9-4269-2016, 2016
Johannes Bühl, Patric Seifert, Alexander Myagkov, and Albert Ansmann
Atmos. Chem. Phys., 16, 10609–10620, https://doi.org/10.5194/acp-16-10609-2016, https://doi.org/10.5194/acp-16-10609-2016, 2016
Short summary
Short summary
We probe thin layered clouds with remote sensing instruments from ground in order to get insight into atmospheric processes like the formation of rain or snow. We think that the findings of our work can be used to improve climate and weather simulations. The present paper presents a new technique that can be used to detect the shape, fall speed and mass of ice particles falling from layered clouds. With such information the impact of cloud ice, e.g., on the lifetime of a cloud, can be estimated.
Alexander Myagkov, Patric Seifert, Ulla Wandinger, Johannes Bühl, and Ronny Engelmann
Atmos. Meas. Tech., 9, 3739–3754, https://doi.org/10.5194/amt-9-3739-2016, https://doi.org/10.5194/amt-9-3739-2016, 2016
Short summary
Short summary
This paper presents first quantitative estimations of ice particle shape at the top of liquid-topped clouds. The estimation is based on polarimetric measurements from a Ka-band cloud radar. 22 cases observed during the ACCEPT (Analysis of the Composition of Clouds with Extended Polarization Techniques) campaign were used. Data from a free-fall chamber were used for the comparison. A good agreement of detected shapes with known shape–temperature dependencies observed in laboratories was found.
Erika Kienast-Sjögren, Christian Rolf, Patric Seifert, Ulrich K. Krieger, Bei P. Luo, Martina Krämer, and Thomas Peter
Atmos. Chem. Phys., 16, 7605–7621, https://doi.org/10.5194/acp-16-7605-2016, https://doi.org/10.5194/acp-16-7605-2016, 2016
Short summary
Short summary
We present a climatology of mid-latitude cirrus cloud properties based on 13 000 hours of automatically analyzed lidar measurements at three different sites. Jungfraujoch,
situated at 3580 m a.s.l., is found to be ideal to measure high and optically thin
cirrus. We use our retrieved optical properties together with a radiation model and
estimate the radiative forcing by mid-latitude cirrus.
All cirrus clouds detected here have a positive net radiative effect.
Holger Baars, Thomas Kanitz, Ronny Engelmann, Dietrich Althausen, Birgit Heese, Mika Komppula, Jana Preißler, Matthias Tesche, Albert Ansmann, Ulla Wandinger, Jae-Hyun Lim, Joon Young Ahn, Iwona S. Stachlewska, Vassilis Amiridis, Eleni Marinou, Patric Seifert, Julian Hofer, Annett Skupin, Florian Schneider, Stephanie Bohlmann, Andreas Foth, Sebastian Bley, Anne Pfüller, Eleni Giannakaki, Heikki Lihavainen, Yrjö Viisanen, Rakesh Kumar Hooda, Sérgio Nepomuceno Pereira, Daniele Bortoli, Frank Wagner, Ina Mattis, Lucja Janicka, Krzysztof M. Markowicz, Peggy Achtert, Paulo Artaxo, Theotonio Pauliquevis, Rodrigo A. F. Souza, Ved Prakesh Sharma, Pieter Gideon van Zyl, Johan Paul Beukes, Junying Sun, Erich G. Rohwer, Ruru Deng, Rodanthi-Elisavet Mamouri, and Felix Zamorano
Atmos. Chem. Phys., 16, 5111–5137, https://doi.org/10.5194/acp-16-5111-2016, https://doi.org/10.5194/acp-16-5111-2016, 2016
Short summary
Short summary
The findings from more than 10 years of global aerosol lidar measurements with Polly systems are summarized, and a data set of optical properties for specific aerosol types is given. An automated data retrieval algorithm for continuous Polly lidar observations is presented and discussed by means of a Saharan dust advection event in Leipzig, Germany. Finally, a statistic on the vertical aerosol distribution including the seasonal variability at PollyNET locations around the globe is presented.
Ronny Engelmann, Thomas Kanitz, Holger Baars, Birgit Heese, Dietrich Althausen, Annett Skupin, Ulla Wandinger, Mika Komppula, Iwona S. Stachlewska, Vassilis Amiridis, Eleni Marinou, Ina Mattis, Holger Linné, and Albert Ansmann
Atmos. Meas. Tech., 9, 1767–1784, https://doi.org/10.5194/amt-9-1767-2016, https://doi.org/10.5194/amt-9-1767-2016, 2016
Short summary
Short summary
The atmospheric science community demands for autonomous and quality-assured vertically resolved measurements of aerosol and cloud properties. For this purpose, a portable lidar called Polly
was developed at TROPOS in 2003. This lidar type was continuously improved with gained experience from EARLINET, worldwide field campaigns, and institute collaborations within the last 10 years. We present recent changes to the setup of our portable multiwavelength Raman and polarization lidar PollyXT.
Ulla Wandinger, Volker Freudenthaler, Holger Baars, Aldo Amodeo, Ronny Engelmann, Ina Mattis, Silke Groß, Gelsomina Pappalardo, Aldo Giunta, Giuseppe D'Amico, Anatoli Chaikovsky, Fiodor Osipenko, Alexander Slesar, Doina Nicolae, Livio Belegante, Camelia Talianu, Ilya Serikov, Holger Linné, Friedhelm Jansen, Arnoud Apituley, Keith M. Wilson, Martin de Graaf, Thomas Trickl, Helmut Giehl, Mariana Adam, Adolfo Comerón, Constantino Muñoz-Porcar, Francesc Rocadenbosch, Michaël Sicard, Sergio Tomás, Diego Lange, Dhiraj Kumar, Manuel Pujadas, Francisco Molero, Alfonso J. Fernández, Lucas Alados-Arboledas, Juan Antonio Bravo-Aranda, Francisco Navas-Guzmán, Juan Luis Guerrero-Rascado, María José Granados-Muñoz, Jana Preißler, Frank Wagner, Michael Gausa, Ivan Grigorov, Dimitar Stoyanov, Marco Iarlori, Vincenco Rizi, Nicola Spinelli, Antonella Boselli, Xuan Wang, Teresa Lo Feudo, Maria Rita Perrone, Ferdinando De Tomasi, and Pasquale Burlizzi
Atmos. Meas. Tech., 9, 1001–1023, https://doi.org/10.5194/amt-9-1001-2016, https://doi.org/10.5194/amt-9-1001-2016, 2016
Short summary
Short summary
We introduce the quality-assurance efforts of the European Aerosol Research Lidar Network (EARLINET) at instrument level. Within several campaigns, 21 EARLINET systems from 18 EARLINET stations were intercompared. A comprehensive strategy for campaign setup and data evaluation was established. The intercomparisons have reinforced our confidence in the EARLINET data quality and allowed us to draw conclusions on necessary system improvements and to identify major challenges for our future work.
A. Skupin, A. Ansmann, R. Engelmann, P. Seifert, and T. Müller
Atmos. Chem. Phys., 16, 1863–1876, https://doi.org/10.5194/acp-16-1863-2016, https://doi.org/10.5194/acp-16-1863-2016, 2016
A. Myagkov, P. Seifert, M. Bauer-Pfundstein, and U. Wandinger
Atmos. Meas. Tech., 9, 469–489, https://doi.org/10.5194/amt-9-469-2016, https://doi.org/10.5194/amt-9-469-2016, 2016
Short summary
Short summary
In this paper a newly developed scanning 35 GHz cloud radar MIRA-35 is described. The issues concerned with implementation, polarization calibration, and data processing are considered. Also, an algorithm for a characterization of shape and orientation distribution based on polarimetric observations from the cloud radar is presented. For demonstration, the developed retrieval technique is applied to a cloud system containing ice crystals with different habits.
L. Belegante, J. A. Bravo-Aranda, V. Freudenthaler, D. Nicolae, A. Nemuc, L. Alados-Arboledas, A. Amodeo, G. Pappalardo, G. D’Amico, R. Engelmann, H. Baars, U. Wandinger, A. Papayannis, P. Kokkalis, and S. N. Pereira
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2015-337, https://doi.org/10.5194/amt-2015-337, 2016
Revised manuscript has not been submitted
Short summary
Short summary
This study aims to present techniques developed to calibrate the lidar depolarization channels.
The experimental approach of the paper is designed to present how calibration procedures are implemented. Most of the literature is focused on the theoretical perspective of the topic and practical issues usually remain an open topic. A hands on approach for the assessment of the lidar polarization sensitivity is welcomed since most of these techniques require comprehensive practical description.
D. Merk, H. Deneke, B. Pospichal, and P. Seifert
Atmos. Chem. Phys., 16, 933–952, https://doi.org/10.5194/acp-16-933-2016, https://doi.org/10.5194/acp-16-933-2016, 2016
Short summary
Short summary
A 2-year data set is analyzed to evaluate the consistency and limitations of current ground-based and satellite-retrieved cloud property data sets. We demonstrate that neither the assumption of a completely adiabatic cloud nor the assumption of a constant sub-adiabatic factor is fulfilled. As cloud adiabaticity is required to estimate the cloud droplet number concentration, but is not available from passive satellite observations, we need an independent method to estimate the adiabatic factor.
J. Schmidt, A. Ansmann, J. Bühl, and U. Wandinger
Atmos. Chem. Phys., 15, 10687–10700, https://doi.org/10.5194/acp-15-10687-2015, https://doi.org/10.5194/acp-15-10687-2015, 2015
M. Simmel, J. Bühl, A. Ansmann, and I. Tegen
Atmos. Chem. Phys., 15, 10453–10470, https://doi.org/10.5194/acp-15-10453-2015, https://doi.org/10.5194/acp-15-10453-2015, 2015
Short summary
Short summary
The paper combines remote sensing observations and detailed cloud modeling. It was shown that the main features of the observations could be captured which allows one to perform sensitivity studies. Those show that the liquid phase is mainly determined by the dynamical parameters of the model, whereas the ice phase is dominated by microphysical parameters such as ice nuclei number and ice particle shape.
E. Giannakaki, A. Pfüller, K. Korhonen, T. Mielonen, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, M. Josipovic, P. Tiitta, K. Chiloane, S. Piketh, H. Lihavainen, K. E. J. Lehtinen, and M. Komppula
Atmos. Chem. Phys., 15, 5429–5442, https://doi.org/10.5194/acp-15-5429-2015, https://doi.org/10.5194/acp-15-5429-2015, 2015
Short summary
Short summary
In this study we summarize 1 year of Raman lidar observations over South Africa. The analyses of lidar measurements presented here could assist in bridging existing gaps in the knowledge of vertical distribution of aerosols above South Africa, since limited long-term data of this type are available for this region. For the first time, we have been able to cover the full seasonal cycle on geometrical characteristics and optical properties of free tropospheric aerosol layers in the region.
T. Kanitz, A. Ansmann, A. Foth, P. Seifert, U. Wandinger, R. Engelmann, H. Baars, D. Althausen, C. Casiccia, and F. Zamorano
Atmos. Meas. Tech., 7, 2061–2072, https://doi.org/10.5194/amt-7-2061-2014, https://doi.org/10.5194/amt-7-2061-2014, 2014
F. Dahlkötter, M. Gysel, D. Sauer, A. Minikin, R. Baumann, P. Seifert, A. Ansmann, M. Fromm, C. Voigt, and B. Weinzierl
Atmos. Chem. Phys., 14, 6111–6137, https://doi.org/10.5194/acp-14-6111-2014, https://doi.org/10.5194/acp-14-6111-2014, 2014
K. Korhonen, E. Giannakaki, T. Mielonen, A. Pfüller, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, A. Ramandh, L. Ntsangwane, M. Josipovic, P. Tiitta, G. Fourie, I. Ngwana, K. Chiloane, and M. Komppula
Atmos. Chem. Phys., 14, 4263–4278, https://doi.org/10.5194/acp-14-4263-2014, https://doi.org/10.5194/acp-14-4263-2014, 2014
A. Skupin, A. Ansmann, R. Engelmann, H. Baars, and T. Müller
Atmos. Meas. Tech., 7, 701–712, https://doi.org/10.5194/amt-7-701-2014, https://doi.org/10.5194/amt-7-701-2014, 2014
Related subject area
Subject: Clouds | Technique: Remote Sensing | Topic: Data Processing and Information Retrieval
Triple frequency radar retrieval of microphysical properties of snow
Physical characteristics of frozen hydrometeors inferred with parameter estimation
Cloud height measurement by a network of all-sky imagers
Increasing the spatial resolution of cloud property retrievals from Meteosat SEVIRI by use of its high-resolution visible channel: implementation and examples
Why we need radar, lidar, and solar radiance observations to constrain ice cloud microphysics
Estimating the optical extinction of liquid water clouds in the cloud base region
W-band radar observations for fog forecast improvement: an analysis of model and forward operator errors
Retrieving microphysical properties of concurrent pristine ice and snow using polarimetric radar observations
Identification of snowfall microphysical processes from Eulerian vertical gradients of polarimetric radar variables
Identifying insects, clouds, and precipitation using vertically pointing polarimetric radar Doppler velocity spectra
MICRU: an effective cloud fraction algorithm designed for UV–vis satellite instruments with large viewing angles
A simplified method for the detection of convection using high-resolution imagery from GOES-16
Introducing hydrometeor orientation into all-sky microwave and submillimeter assimilation
Version 4 CALIPSO Imaging Infrared Radiometer ice and liquid water cloud microphysical properties – Part II: Results over oceans
Version 4 CALIPSO Imaging Infrared Radiometer ice and liquid water cloud microphysical properties – Part I: The retrieval algorithms
Observation of cirrus clouds with GLORIA during the WISE campaign: detection methods and cirrus characterization
Comparison of mid-latitude single and mixed-phase cloud optical depth from co-located infrared spectrometer and backscatter LiDAR measurements
Applying machine learning methods to detect convection using Geostationary Operational Environmental Satellite-16 (GOES-16) advanced baseline imager (ABI) data
A new method to detect and classify polar stratospheric nitric acid trihydrate clouds derived from radiative transfer simulations and its first application to airborne infrared limb emission observations
A study of polarimetric error induced by satellite motion: application to the 3MI and similar sensors
A robust low-level cloud and clutter discrimination method for ground-based millimeter-wavelength cloud radar
Two-dimensional and multi-channel feature detection algorithm for the CALIPSO lidar measurements
Analysis of 3D cloud effects in OCO-2 XCO2 retrievals
Improving cloud type classification of ground-based images using region covariance descriptors
Global cloud property models for real-time triage on board visible–shortwave infrared spectrometers
Applying deep learning to NASA MODIS data to create a community record of marine low-cloud mesoscale morphology
Microwave single-scattering properties of non-spheroidal raindrops
Determining cloud thermodynamic phase from the polarized Micro Pulse Lidar
Improved cloud detection over sea ice and snow during Arctic summer using MERIS data
A kernel-driven BRDF model to inform satellite-derived visible anvil cloud detection
Cloud-top pressure retrieval with DSCOVR EPIC oxygen A- and B-band observations
Estimating total attenuation using Rayleigh targets at cloud top: applications in multilayer and mixed-phase clouds observed by ground-based multifrequency radars
A new Orbiting Carbon Observatory 2 cloud flagging method and rapid retrieval of marine boundary layer cloud properties
CALIOP V4 cloud thermodynamic phase assignment and the impact of near-nadir viewing angles
Detection of the cloud liquid water path horizontal inhomogeneity in a coastline area by means of ground-based microwave observations: feasibility study
Synergistic radar and radiometer retrievals of ice hydrometeors
Improvement in cloud retrievals from VIIRS through the use of infrared absorption channels constructed from VIIRS+CrIS data fusion
Using two-stream theory to capture fluctuations of satellite-perceived TOA SW radiances reflected from clouds over ocean
Exploration of machine learning methods for the classification of infrared limb spectra of polar stratospheric clouds
Three-dimensional wind profiles using a stabilized shipborne cloud radar in wind profiler mode
Low-level liquid cloud properties during ORACLES retrieved using airborne polarimetric measurements and a neural network algorithm
A machine-learning-based cloud detection and thermodynamic-phase classification algorithm using passive spectral observations
SegCloud: a novel cloud image segmentation model using a deep convolutional neural network for ground-based all-sky-view camera observation
Spatial distribution of cloud droplet size properties from Airborne Hyper-Angular Rainbow Polarimeter (AirHARP) measurements
Towards objective identification and tracking of convective outflow boundaries in next-generation geostationary satellite imagery
Cloud detection over snow and ice with oxygen A- and B-band observations from the Earth Polychromatic Imaging Camera (EPIC)
Ground-based observations of cloud and drizzle liquid water path in stratocumulus clouds
Increasing the spatial resolution of cloud property retrievals from Meteosat SEVIRI by use of its high-resolution visible channel: evaluation of candidate approaches with MODIS observations
Estimation of cloud optical thickness, single scattering albedo and effective droplet radius using a shortwave radiative closure study in Payerne
Towards an operational Ice Cloud Imager (ICI) retrieval product
Kamil Mroz, Alessandro Battaglia, Cuong Nguyen, Andrew Heymsfield, Alain Protat, and Mengistu Wolde
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-227, https://doi.org/10.5194/amt-2021-227, 2021
Revised manuscript accepted for AMT
Short summary
Short summary
A method for estimating microphysical properties of ice clouds based on the radar measurements is presented. The algorithm exploits the information provided by differences in the radar response at different frequency bands in a relation to changes in the snow morphology. The inversion scheme is based on a statistical relation between the radar simulations and the properties of snow calculated from in cloud samplings.
Alan J. Geer
Atmos. Meas. Tech., 14, 5369–5395, https://doi.org/10.5194/amt-14-5369-2021, https://doi.org/10.5194/amt-14-5369-2021, 2021
Short summary
Short summary
Satellite observations sensitive to cloud and precipitation help improve the quality of weather forecasts. However, they are sensitive to things that models do not forecast, such as the shapes and sizes of snow and ice particles. These details can be estimated from the observations themselves and then incorporated in the satellite simulators used in weather forecasting. This approach, known as parameter estimation, will be increasingly useful to build models of poorly known physical processes.
Niklas Benedikt Blum, Bijan Nouri, Stefan Wilbert, Thomas Schmidt, Ontje Lünsdorf, Jonas Stührenberg, Detlev Heinemann, Andreas Kazantzidis, and Robert Pitz-Paal
Atmos. Meas. Tech., 14, 5199–5224, https://doi.org/10.5194/amt-14-5199-2021, https://doi.org/10.5194/amt-14-5199-2021, 2021
Short summary
Short summary
Cloud base height (CBH) is important, e.g., to forecast solar irradiance and, with it, photovoltaic production. All-sky imagers (ASIs), cameras monitoring the sky above their point of installation, can provide such forecasts and also measure CBH. We present a network of ASIs to measure CBH. The network provides numerous readings of CBH simultaneously. We combine these with a statistical procedure. Validation attests to significantly higher accuracy of the combination compared to two ASIs alone.
Hartwig Deneke, Carola Barrientos-Velasco, Sebastian Bley, Anja Hünerbein, Stephan Lenk, Andreas Macke, Jan Fokke Meirink, Marion Schroedter-Homscheidt, Fabian Senf, Ping Wang, Frank Werner, and Jonas Witthuhn
Atmos. Meas. Tech., 14, 5107–5126, https://doi.org/10.5194/amt-14-5107-2021, https://doi.org/10.5194/amt-14-5107-2021, 2021
Short summary
Short summary
The SEVIRI instrument flown on the European geostationary Meteosat satellites acquires multi-spectral images at a relatively coarse pixel resolution of 3 × 3 km2, but it also has a broadband high-resolution visible channel with 1 × 1 km2 spatial resolution. In this study, the modification of an existing cloud property and solar irradiance retrieval to use this channel to improve the spatial resolution of its output products as well as the resulting benefits for applications are described.
Florian Ewald, Silke Groß, Martin Wirth, Julien Delanoë, Stuart Fox, and Bernhard Mayer
Atmos. Meas. Tech., 14, 5029–5047, https://doi.org/10.5194/amt-14-5029-2021, https://doi.org/10.5194/amt-14-5029-2021, 2021
Short summary
Short summary
In this study, we show how solar radiance observations can be used to validate and further constrain ice cloud microphysics retrieved from the synergy of radar–lidar measurements. Since most radar–lidar retrievals rely on a global assumption about the ice particle shape, ice water content and particle size biases are to be expected in individual cloud regimes. In this work, we identify and correct these biases by reconciling simulated and measured solar radiation reflected from these clouds.
Karolina Sarna, David P. Donovan, and Herman W. J. Russchenberg
Atmos. Meas. Tech., 14, 4959–4970, https://doi.org/10.5194/amt-14-4959-2021, https://doi.org/10.5194/amt-14-4959-2021, 2021
Short summary
Short summary
We show a method for obtaining cloud optical extinction with a lidar system. We use a scheme in which a lidar signal is inverted based on the estimated value of cloud extinction at the far end of the cloud and apply a correction for multiple scattering within the cloud and a range resolution correction. By applying our technique, we show that it is possible to obtain the cloud optical extinction with an error better than 5 % up to 90 m within the cloud.
Alistair Bell, Pauline Martinet, Olivier Caumont, Benoît Vié, Julien Delanoë, Jean-Charles Dupont, and Mary Borderies
Atmos. Meas. Tech., 14, 4929–4946, https://doi.org/10.5194/amt-14-4929-2021, https://doi.org/10.5194/amt-14-4929-2021, 2021
Short summary
Short summary
This paper presents work towards making retrievals on the liquid water content in fog and low clouds. Future retrievals will rely on a radar simulator and high-resolution forecast. In this work, real observations are used to assess the errors associated with the simulator and forecast. A selection method to reduce errors associated with the forecast is proposed. It is concluded that the distribution of errors matches the requirements for future retrievals.
Nicholas J. Kedzuf, J. Christine Chiu, V. Chandrasekar, Sounak Biswas, Shashank S. Joshil, Yinghui Lu, Peter Jan van Leeuwen, Christopher Westbrook, Yann Blanchard, and Sebastian O'Shea
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-168, https://doi.org/10.5194/amt-2021-168, 2021
Revised manuscript accepted for AMT
Short summary
Short summary
Ice clouds play a key role in our climate system, due to their strong controls on precipitation and radiation budget. However, it is difficult to characterize co-existing ice species using radar observations. We present a new method that separates the radar signals of pristine ice embedded in snow aggregates and retrieves their respective abundances and sizes for the first time. The ability to provide their quantitative microphysical properties will open many research opportunities.
Noémie Planat, Josué Gehring, Étienne Vignon, and Alexis Berne
Atmos. Meas. Tech., 14, 4543–4564, https://doi.org/10.5194/amt-14-4543-2021, https://doi.org/10.5194/amt-14-4543-2021, 2021
Short summary
Short summary
We implement a new method to identify microphysical processes during cold precipitation events based on the sign of the vertical gradient of polarimetric radar variables. We analytically asses the meteorological conditions for this vertical analysis to hold, apply it on two study cases and successfully compare it with other methods informing about the microphysics. Finally, we are able to obtain the main vertical structure and characteristics of the different processes during these study cases.
Christopher R. Williams, Karen L. Johnson, Scott E. Giangrande, Joseph C. Hardin, Ruşen Öktem, and David M. Romps
Atmos. Meas. Tech., 14, 4425–4444, https://doi.org/10.5194/amt-14-4425-2021, https://doi.org/10.5194/amt-14-4425-2021, 2021
Short summary
Short summary
In addition to detecting clouds, vertically pointing cloud radars detect individual insects passing over head. If these insects are not identified and removed from raw observations, then radar-derived cloud properties will be contaminated. This work identifies clouds in radar observations due to their continuous and smooth structure in time, height, and velocity. Cloud masks are produced that identify cloud vertical structure that are free of insect contamination.
Holger Sihler, Steffen Beirle, Steffen Dörner, Marloes Gutenstein-Penning de Vries, Christoph Hörmann, Christian Borger, Simon Warnach, and Thomas Wagner
Atmos. Meas. Tech., 14, 3989–4031, https://doi.org/10.5194/amt-14-3989-2021, https://doi.org/10.5194/amt-14-3989-2021, 2021
Short summary
Short summary
MICRU is an algorithm for the retrieval of effective cloud fractions (CFs) from satellite measurements. CFs describe the amount of clouds, which have a significant impact on the vertical sensitivity profile of trace gases like NO2 and HCHO. MICRU retrieves small CFs with an accuracy of 0.04 over the entire satellite swath. It features an empirical surface reflectivity model accounting for physical anisotropy (BRDF, sun glitter) and instrumental effects. MICRU is also applicable to imager data.
Yoonjin Lee, Christian D. Kummerow, and Milija Zupanski
Atmos. Meas. Tech., 14, 3755–3771, https://doi.org/10.5194/amt-14-3755-2021, https://doi.org/10.5194/amt-14-3755-2021, 2021
Short summary
Short summary
This study suggests two methods to detect convection using 1 min data from GOES-16: one method detects early convective clouds using their vertical growth rate and the other method detects mature convective clouds using their lumpy cloud top surfaces. Applying the two methods to 1-month data showed that the accuracy of the combined methods was 85.8 % and showed their potential to be used in regions where radar data are not available.
Vasileios Barlakas, Alan J. Geer, and Patrick Eriksson
Atmos. Meas. Tech., 14, 3427–3447, https://doi.org/10.5194/amt-14-3427-2021, https://doi.org/10.5194/amt-14-3427-2021, 2021
Short summary
Short summary
Oriented nonspherical ice particles induce polarization that is ignored when cloud-sensitive satellite observations are used in numerical weather prediction systems. We present a simple approach for approximating particle orientation, requiring minor adaption of software and no additional calculation burden. With this approach, the system realistically simulates the observed polarization patterns, increasing the physical consistency between instruments with different polarizations.
Anne Garnier, Jacques Pelon, Nicolas Pascal, Mark A. Vaughan, Philippe Dubuisson, Ping Yang, and David L. Mitchell
Atmos. Meas. Tech., 14, 3277–3299, https://doi.org/10.5194/amt-14-3277-2021, https://doi.org/10.5194/amt-14-3277-2021, 2021
Short summary
Short summary
The IIR Level 2 data products include cloud effective emissivities and cloud microphysical properties such as effective diameter (De) and ice or liquid water path estimates. This paper (Part II) shows retrievals over ocean and describes the improvements made with respect to version 3 as a result of the significant changes implemented in the version 4 algorithms, which are presented in a companion paper (Part I).
Anne Garnier, Jacques Pelon, Nicolas Pascal, Mark A. Vaughan, Philippe Dubuisson, Ping Yang, and David L. Mitchell
Atmos. Meas. Tech., 14, 3253–3276, https://doi.org/10.5194/amt-14-3253-2021, https://doi.org/10.5194/amt-14-3253-2021, 2021
Short summary
Short summary
The IIR Level 2 data products include cloud effective emissivities and cloud microphysical properties such as effective diameter (De) and ice or liquid water path estimates. This paper (Part I) describes the improvements in the V4 algorithms compared to those used in the version 3 (V3) release, while results are presented in a companion paper (Part II).
Irene Bartolome Garcia, Reinhold Spang, Jörn Ungermann, Sabine Griessbach, Martina Krämer, Michael Höpfner, and Martin Riese
Atmos. Meas. Tech., 14, 3153–3168, https://doi.org/10.5194/amt-14-3153-2021, https://doi.org/10.5194/amt-14-3153-2021, 2021
Short summary
Short summary
Cirrus clouds contribute to the general radiation budget of the Earth. Measuring optically thin clouds is challenging but the IR limb sounder GLORIA possesses the necessary technical characteristics to make it possible. This study analyses data from the WISE campaign obtained with GLORIA. We developed a cloud detection method and derived characteristics of the observed cirrus-like cloud top, cloud bottom or position with respect to the tropopause.
Gianluca Di Natale, Marco Barucci, Claudio Belotti, Giovanni Bianchini, Francesco D'Amato, Samuele Del Bianco, Marco Gai, Alessio Montori, Ralf Sussmann, Silvia Viciani, Hannes Vogelmann, and Luca Palchetti
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-104, https://doi.org/10.5194/amt-2021-104, 2021
Revised manuscript accepted for AMT
Short summary
Short summary
The importance of the cirrus and mixed phase clouds in the Earth Radiation Budget has been proven by many studies, since they interact with the shortwave and thermal radiation coming from the sun and the Earth. In this paper the main properties which characterize cirrus clouds are retrieved from the far infrared spectral and lidar measurements performed on field during Winter 2018–2019 on the Zugspitze Mount (Germany) within the FIRMOS project, founded by the European Space Agency (ESA).
Yoonjin Lee, Christian D. Kummerow, and Imme Ebert-Uphoff
Atmos. Meas. Tech., 14, 2699–2716, https://doi.org/10.5194/amt-14-2699-2021, https://doi.org/10.5194/amt-14-2699-2021, 2021
Short summary
Short summary
Convective clouds are usually associated with intense rain that can cause severe damage, and thus it is important to accurately detect convective clouds. This study develops a machine learning model that can identify convective clouds from five temporal visible and infrared images as humans can point at convective regions by finding bright and bubbling areas. The results look promising when compared to radar-derived products, which are commonly used for detecting convection.
Christoph Kalicinsky, Sabine Griessbach, and Reinhold Spang
Atmos. Meas. Tech., 14, 1893–1915, https://doi.org/10.5194/amt-14-1893-2021, https://doi.org/10.5194/amt-14-1893-2021, 2021
Short summary
Short summary
For an airborne viewing geometry, radiative transfer simulations of infrared limb emission spectra in the presence of polar stratospheric clouds – nitric acid trihydrate (NAT), supercooled ternary solution, ice, and mixtures – were used to develop a size-sensitive NAT detection algorithm. Characteristic size-dependent spectral features in the 810–820 cm−1 region were exploited to subgroup the NAT into three size regimes: small NAT (≤ 1.0 μm), medium NAT (1.5–4.0 μm), and large NAT (≥ 3.5 μm).
Souichiro Hioki, Jérôme Riedi, and Mohamed S. Djellali
Atmos. Meas. Tech., 14, 1801–1816, https://doi.org/10.5194/amt-14-1801-2021, https://doi.org/10.5194/amt-14-1801-2021, 2021
Short summary
Short summary
This research estimates the magnitude of a motion-induced error in the measurement of polarimetric state of light by a planned instrument on a future satellite. We discovered that the motion-induced error can not be cancelled out by spatiotemporal averaging, but it can be predicted from the along-track change of the intensity of light. With the estimated statistics and the simulation model, this research paves a way to provide pixel-level quality information in the future satellite products.
Xiaoyu Hu, Jinming Ge, Jiajing Du, Qinghao Li, Jianping Huang, and Qiang Fu
Atmos. Meas. Tech., 14, 1743–1759, https://doi.org/10.5194/amt-14-1743-2021, https://doi.org/10.5194/amt-14-1743-2021, 2021
Short summary
Short summary
Cloud radars are powerful instruments that can probe detailed cloud structures. However, radar echoes in the lower atmosphere are always contaminated by clutter. We proposed a multi-dimensional probability distribution function that can effectively discriminate low-level clouds from clutter by considering their different features in several variables. We applied this method to the radar observations at the SACOL site and found the results have good agreement with lidar detection.
Thibault Vaillant de Guélis, Mark A. Vaughan, David M. Winker, and Zhaoyan Liu
Atmos. Meas. Tech., 14, 1593–1613, https://doi.org/10.5194/amt-14-1593-2021, https://doi.org/10.5194/amt-14-1593-2021, 2021
Short summary
Short summary
We introduce a new lidar feature detection algorithm that dramatically improves the fine details of layers identified in the CALIOP data. By applying our two-dimensional scanning technique to the measurements in all three channels, we minimize false positives while accurately identifying previously undetected features such as subvisible cirrus and the full vertical extent of dense smoke plumes. Multiple comparisons to version 4.2 CALIOP retrievals illustrate the scope of the improvements made.
Steven T. Massie, Heather Cronk, Aronne Merrelli, Christopher O'Dell, K. Sebastian Schmidt, Hong Chen, and David Baker
Atmos. Meas. Tech., 14, 1475–1499, https://doi.org/10.5194/amt-14-1475-2021, https://doi.org/10.5194/amt-14-1475-2021, 2021
Short summary
Short summary
The OCO-2 science team is working to retrieve CO2 measurements that can be used by the carbon cycle community to calculate regional sources and sinks of CO2. The retrieved data, however, are in need of improvements in accuracy. This paper discusses several ways in which 3D cloud metrics (such as the distance of a measurement to the nearest cloud) can be used to account for cloud effects in the OCO-2 CO2 data files.
Yuzhu Tang, Pinglv Yang, Zeming Zhou, Delu Pan, Jianyu Chen, and Xiaofeng Zhao
Atmos. Meas. Tech., 14, 737–747, https://doi.org/10.5194/amt-14-737-2021, https://doi.org/10.5194/amt-14-737-2021, 2021
Short summary
Short summary
An automatic cloud classification method on whole-sky images is presented. We first extract multiple pixel-level features to form region covariance descriptors (RCovDs) and then encode RCovDs by the Riemannian bag-of-feature (BoF) method to output the histogram representation. Reults show that a very high prediction accuracy can be obtained with a small number of training samples, which validate the proposed method and exhibit the competitive performance against state-of-the-art methods.
Macey W. Sandford, David R. Thompson, Robert O. Green, Brian H. Kahn, Raffaele Vitulli, Steve Chien, Amruta Yelamanchili, and Winston Olson-Duvall
Atmos. Meas. Tech., 13, 7047–7057, https://doi.org/10.5194/amt-13-7047-2020, https://doi.org/10.5194/amt-13-7047-2020, 2020
Short summary
Short summary
We demonstrate an onboard cloud-screening approach to significantly reduce the amount of cloud-contaminated data transmitted from orbit. We have produced location-specific models that improve performance by taking into account the unique cloud statistics in different latitudes. We have shown that screening clouds based on their location or surface type will improve the ability for a cloud-screening tool to improve the volume of usable science data.
Tianle Yuan, Hua Song, Robert Wood, Johannes Mohrmann, Kerry Meyer, Lazaros Oreopoulos, and Steven Platnick
Atmos. Meas. Tech., 13, 6989–6997, https://doi.org/10.5194/amt-13-6989-2020, https://doi.org/10.5194/amt-13-6989-2020, 2020
Short summary
Short summary
We use deep transfer learning techniques to classify satellite cloud images into different morphology types. It achieves the state-of-the-art results and can automatically process a large amount of satellite data. The algorithm will help low-cloud researchers to better understand their mesoscale organizations.
Robin Ekelund, Patrick Eriksson, and Michael Kahnert
Atmos. Meas. Tech., 13, 6933–6944, https://doi.org/10.5194/amt-13-6933-2020, https://doi.org/10.5194/amt-13-6933-2020, 2020
Short summary
Short summary
Raindrops become flattened due to aerodynamic drag as they increase in mass and fall speed. This study calculated the electromagnetic interaction between microwave radiation and non-spheroidal raindrops. The calculations are made publicly available to the scientific community, in order to promote accurate representations of raindrops in measurements. Tests show that the drop shape can have a noticeable effect on microwave observations of heavy rainfall.
Jasper R. Lewis, James R. Campbell, Sebastian A. Stewart, Ivy Tan, Ellsworth J. Welton, and Simone Lolli
Atmos. Meas. Tech., 13, 6901–6913, https://doi.org/10.5194/amt-13-6901-2020, https://doi.org/10.5194/amt-13-6901-2020, 2020
Short summary
Short summary
In this work, the authors describe a process to determine the thermodynamic cloud phase using the Micro Pulse Lidar Network volume depolarization ratio measurements and temperature profiles from the Global Modeling and Assimilation Office GEOS-5 model. A multi-year analysis and comparisons to supercooled liquid water fractions derived from CALIPSO satellite measurements are used to demonstrate the efficacy of the method.
Larysa Istomina, Henrik Marks, Marcus Huntemann, Georg Heygster, and Gunnar Spreen
Atmos. Meas. Tech., 13, 6459–6472, https://doi.org/10.5194/amt-13-6459-2020, https://doi.org/10.5194/amt-13-6459-2020, 2020
Benjamin R. Scarino, Kristopher Bedka, Rajendra Bhatt, Konstantin Khlopenkov, David R. Doelling, and William L. Smith Jr.
Atmos. Meas. Tech., 13, 5491–5511, https://doi.org/10.5194/amt-13-5491-2020, https://doi.org/10.5194/amt-13-5491-2020, 2020
Short summary
Short summary
This paper highlights a technique for facilitating anvil cloud detection based on visible observations that relies on comparative analysis with expected cloud reflectance for a given set of angles. A 1-year database of anvil-identified pixels, as determined from IR observations, from several geostationary satellites was used to construct a bidirectional reflectance distribution function model to quantify typical anvil reflectance across almost all expected viewing, solar, and azimuth angles.
Bangsheng Yin, Qilong Min, Emily Morgan, Yuekui Yang, Alexander Marshak, and Anthony B. Davis
Atmos. Meas. Tech., 13, 5259–5275, https://doi.org/10.5194/amt-13-5259-2020, https://doi.org/10.5194/amt-13-5259-2020, 2020
Short summary
Short summary
Cloud-top pressure (CTP) is an important cloud property for climate and weather studies. Based on differential oxygen absorption, both oxygen A-band and B-band pairs can be used to retrieve CTP. However, it is currently very challenging to perform a CTP retrieval accurately due to the complicated in-cloud penetration effect. To address this issue, we propose an analytic transfer inverse model for DSCOVR EPIC observations to retrieve CTP considering in-cloud photon penetration.
Frédéric Tridon, Alessandro Battaglia, and Stefan Kneifel
Atmos. Meas. Tech., 13, 5065–5085, https://doi.org/10.5194/amt-13-5065-2020, https://doi.org/10.5194/amt-13-5065-2020, 2020
Short summary
Short summary
The droplets and ice crystals composing clouds and precipitation interact with microwaves and can therefore be observed by radars, but they can also attenuate the signal they emit. By combining the observations made by two ground-based radars, this study describes an original approach for estimating such attenuation. As a result, the latter can be not only corrected in the radar observations but also exploited for providing an accurate characterization of droplet and ice crystal properties.
Mark Richardson, Matthew D. Lebsock, James McDuffie, and Graeme L. Stephens
Atmos. Meas. Tech., 13, 4947–4961, https://doi.org/10.5194/amt-13-4947-2020, https://doi.org/10.5194/amt-13-4947-2020, 2020
Short summary
Short summary
We previously combined CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) lidar data and reflected-sunlight measurements from OCO-2 (Orbiting Carbon Observatory 2) for information about low clouds over oceans. The satellites are no longer formation-flying, so this work is a step towards getting new information about these clouds using only OCO-2. We can rapidly and accurately identify liquid oceanic clouds and obtain their height better than a widely used passive sensor.
Melody A. Avery, Robert A. Ryan, Brian J. Getzewich, Mark A. Vaughan, David M. Winker, Yongxiang Hu, Anne Garnier, Jacques Pelon, and Carolus A. Verhappen
Atmos. Meas. Tech., 13, 4539–4563, https://doi.org/10.5194/amt-13-4539-2020, https://doi.org/10.5194/amt-13-4539-2020, 2020
Short summary
Short summary
CALIOP data users will find more cloud layers detected in V4, with edges that extend further than in V3, for an increase in total atmospheric cloud volume of 6 %–9 % for high-confidence cloud phases and 1 %–2 % for all cloudy bins, including cloud fringes and unknown cloud phases. In V4 there are many fewer cloud layers identified as horizontally oriented ice, particularly in the 3° off-nadir view. Depolarization at 532 nm is the predominant parameter determining cloud thermodynamic phase.
Vladimir S. Kostsov, Dmitry V. Ionov, and Anke Kniffka
Atmos. Meas. Tech., 13, 4565–4587, https://doi.org/10.5194/amt-13-4565-2020, https://doi.org/10.5194/amt-13-4565-2020, 2020
Short summary
Short summary
Previously, observations from satellites provided evidence for systematic differences between the values of the cloud liquid water path over land and water areas in northern Europe. An attempt is made to detect such differences by means of ground-based microwave measurements performed near the coastline of the Gulf of Finland. The results demonstrate the existence of the cloud liquid water path gradient, which is positive as in the case of the satellite measurements (larger values over land).
Simon Pfreundschuh, Patrick Eriksson, Stefan A. Buehler, Manfred Brath, David Duncan, Richard Larsson, and Robin Ekelund
Atmos. Meas. Tech., 13, 4219–4245, https://doi.org/10.5194/amt-13-4219-2020, https://doi.org/10.5194/amt-13-4219-2020, 2020
Short summary
Short summary
The next generation of European operational weather satellites will carry a novel microwave sensor, the Ice Cloud Imager (ICI), which will provide observations of clouds at microwave frequencies that were not available before. We investigate the potential benefits of combining observations from ICI with that of a radar. We find that such combined observations provide additional information on the properties of the cloud and help to reduce uncertainties in retrieved mass and number densities.
Yue Li, Bryan A. Baum, Andrew K. Heidinger, W. Paul Menzel, and Elisabeth Weisz
Atmos. Meas. Tech., 13, 4035–4049, https://doi.org/10.5194/amt-13-4035-2020, https://doi.org/10.5194/amt-13-4035-2020, 2020
Short summary
Short summary
Use of VIIRS+CrIS fusion products, which provide VIIRS with MODIS-like IR sounding channels, improves cloud mask, cloud phase, and cloud top height retrievals when compared to those using VIIRS data only. NOAA CLAVR-x cloud retrievals for both S-NPP and NOAA-20 data are evaluated through comparisons to the CALIPSO v4 and MODIS Collection 6.1 cloud products. Cloud height retrievals show significant improvement for semitransparent ice clouds, with a reduction in retrieval uncertainties.
Florian Tornow, Carlos Domenech, Howard W. Barker, René Preusker, and Jürgen Fischer
Atmos. Meas. Tech., 13, 3909–3922, https://doi.org/10.5194/amt-13-3909-2020, https://doi.org/10.5194/amt-13-3909-2020, 2020
Short summary
Short summary
Clouds reflect sunlight unevenly, which makes it difficult to quantify the portion reflected back to space via satellite observation. To improve quantification, we propose a new statistical model that incorporates more satellite-inferred cloud and atmospheric properties than state-of-the-art models. We use concepts from radiative transfer theory that we statistically optimize to fit observations. The new model often explains past satellite observations better and predicts reflection plausibly.
Rocco Sedona, Lars Hoffmann, Reinhold Spang, Gabriele Cavallaro, Sabine Griessbach, Michael Höpfner, Matthias Book, and Morris Riedel
Atmos. Meas. Tech., 13, 3661–3682, https://doi.org/10.5194/amt-13-3661-2020, https://doi.org/10.5194/amt-13-3661-2020, 2020
Short summary
Short summary
Polar stratospheric clouds (PSCs) play a key role in polar ozone depletion in the stratosphere. In this paper, we explore the potential of applying machine learning (ML) methods to classify PSC observations of infrared spectra to classify PSC types. ML methods have proved to reach results in line with those obtained using well-established approaches. Among the considered ML methods, random forest (RF) seems to be the most promising one, being able to produce explainable classification results.
Alain Protat and Ian McRobert
Atmos. Meas. Tech., 13, 3609–3620, https://doi.org/10.5194/amt-13-3609-2020, https://doi.org/10.5194/amt-13-3609-2020, 2020
Short summary
Short summary
Three-dimensional (3D) wind motions play a major role in driving the life cycle of clouds. In this pilot study we have developed a technique to measure the 3D winds in clouds, using a shipborne Doppler cloud radar on a stabilized platform. The stabilized platform is driven to point in a series of predefined directions to collect the required measurements. Comparisons with radiosondes demonstrate that accurate 1 min resolution 3D wind motions can be obtained from this instrumental setup.
Daniel J. Miller, Michal Segal-Rozenhaimer, Kirk Knobelspiesse, Jens Redemann, Brian Cairns, Mikhail Alexandrov, Bastiaan van Diedenhoven, and Andrzej Wasilewski
Atmos. Meas. Tech., 13, 3447–3470, https://doi.org/10.5194/amt-13-3447-2020, https://doi.org/10.5194/amt-13-3447-2020, 2020
Short summary
Short summary
A neural network (NN) is developed and used to retrieve cloud microphysical properties from multiangular and multispectral polarimetric remote sensing observations. The NN is applied to research scanning polarimeter (RSP) observations obtained during the ORACLES field campaign and compared to other co-located remote sensing retrievals of cloud effective radius and optical thickness. A NN approach can advance more complex iterative search retrieval algorithms by providing a quick initial guess.
Chenxi Wang, Steven Platnick, Kerry Meyer, Zhibo Zhang, and Yaping Zhou
Atmos. Meas. Tech., 13, 2257–2277, https://doi.org/10.5194/amt-13-2257-2020, https://doi.org/10.5194/amt-13-2257-2020, 2020
Short summary
Short summary
A machine-learning (ML)-based approach that can be used for cloud mask and phase detection is developed. An all-day model that uses infrared (IR) observations and a daytime model that uses shortwave and IR observations from a passive instrument are trained separately for different surface types. The training datasets are selected by using reference pixel types from collocated space lidar. The ML approach is validated carefully and the overall performance is better than traditional methods.
Wanyi Xie, Dong Liu, Ming Yang, Shaoqing Chen, Benge Wang, Zhenzhu Wang, Yingwei Xia, Yong Liu, Yiren Wang, and Chaofan Zhang
Atmos. Meas. Tech., 13, 1953–1961, https://doi.org/10.5194/amt-13-1953-2020, https://doi.org/10.5194/amt-13-1953-2020, 2020
Brent A. McBride, J. Vanderlei Martins, Henrique M. J. Barbosa, William Birmingham, and Lorraine A. Remer
Atmos. Meas. Tech., 13, 1777–1796, https://doi.org/10.5194/amt-13-1777-2020, https://doi.org/10.5194/amt-13-1777-2020, 2020
Short summary
Short summary
Clouds play a large role in the way our Earth system distributes energy. The measurement of cloud droplet size distribution (DSD) is one way to connect small-scale cloud processes to scattered radiation. Our small satellite instrument, the Airborne Hyper-Angular Rainbow Polarimeter, is the first to infer DSDs over a wide spatial cloud field using polarized light. This study improves the way we interpret cloud properties and shows that high-quality science does not require a large taxpayer cost.
Jason M. Apke, Kyle A. Hilburn, Steven D. Miller, and David A. Peterson
Atmos. Meas. Tech., 13, 1593–1608, https://doi.org/10.5194/amt-13-1593-2020, https://doi.org/10.5194/amt-13-1593-2020, 2020
Short summary
Short summary
Objective identification of deep convection outflow boundaries (OFBs) in next-generation geostationary satellite imagery is explored here using motion derived from a tuned advanced optical flow algorithm. Motion discontinuity preservation within the derivation is found crucial for successful OFB tracking between images, which yields new meteorological data for objective systems to use. These results provide the first step towards a fully automated satellite-based OFB identification algorithm.
Yaping Zhou, Yuekui Yang, Meng Gao, and Peng-Wang Zhai
Atmos. Meas. Tech., 13, 1575–1591, https://doi.org/10.5194/amt-13-1575-2020, https://doi.org/10.5194/amt-13-1575-2020, 2020
Short summary
Short summary
Satellite cloud detection over snow and ice has been difficult for passive remote sensing instruments due to the lack of contrast between clouds and the bright and cold surfaces; the Earth Polychromatic Imaging Camera (EPIC) on board the Deep Space Climate Observatory (DSCOVR) has very limited channels. This study investigates the methodology of applying EPIC's two oxygen absorption band pair ratios for cloud detection over snow and ice surfaces.
Maria P. Cadeddu, Virendra P. Ghate, and Mario Mech
Atmos. Meas. Tech., 13, 1485–1499, https://doi.org/10.5194/amt-13-1485-2020, https://doi.org/10.5194/amt-13-1485-2020, 2020
Short summary
Short summary
A combination of ground-based active and passive observations is used to partition cloud and precipitation liquid water path in precipitating stratocumulous clouds. Results show that neglecting scattering effects from drizzle drops leads to 8–15 % overestimation of the liquid amount in the cloud. In closed-cell systems only ~20 % of the available drizzle in the cloud falls below the cloud base, compared to ~40 % in open-cell systems.
Frank Werner and Hartwig Deneke
Atmos. Meas. Tech., 13, 1089–1111, https://doi.org/10.5194/amt-13-1089-2020, https://doi.org/10.5194/amt-13-1089-2020, 2020
Short summary
Short summary
The reliability of remotely sensed cloud variables from space depends on the horizontal resolution of the instrument. This study presents and evaluates several candidate approaches for increasing the spatial resolution of observations from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) from the native 3 km scale to a horizontal resolution of 1 km. It is shown that uncertainties in the derived cloud products can be significantly mitigated by applying an appropriate downscaling scheme.
Christine Aebi, Julian Gröbner, Stelios Kazadzis, Laurent Vuilleumier, Antonis Gkikas, and Niklaus Kämpfer
Atmos. Meas. Tech., 13, 907–923, https://doi.org/10.5194/amt-13-907-2020, https://doi.org/10.5194/amt-13-907-2020, 2020
Short summary
Short summary
Clouds are one of the largest sources of uncertainties in climate models. The current study estimates the cloud optical thickness (COT), the effective droplet radius and the single scattering albedo of stratus–altostratus and cirrus–cirrostratus clouds in Payerne, Switzerland, by combining ground- and satellite-based measurements and radiative transfer models. The estimated values are thereafter compared with data retrieved from other methods. The mean COT is distinct for different seasons.
Patrick Eriksson, Bengt Rydberg, Vinia Mattioli, Anke Thoss, Christophe Accadia, Ulf Klein, and Stefan A. Buehler
Atmos. Meas. Tech., 13, 53–71, https://doi.org/10.5194/amt-13-53-2020, https://doi.org/10.5194/amt-13-53-2020, 2020
Short summary
Short summary
The Ice Cloud Imager (ICI) will be the first operational satellite sensor operating at sub-millimetre wavelengths and this novel mission will thus provide important new data to weather forecasting and climate studies. The series of ICI instruments will together cover about 20 years. This article presents the basic technical characteristics of the sensor and outlines the day-one operational retrievals. An updated estimation of the expected retrieval performance is also presented.
Cited articles
Baumgardner, D., Abel, S. J., Axisa, D., Cotton, R., Crosier, J., Field, P.,
Gurganus, C., Heymsfield, A., Korolev, A., Krämer, M., Lawson, P.,
McFarquhar, G., Ulanowski, Z., and Um, J.: Cloud Ice Properties: In Situ
Measurement Challenges, Meteor. Mon., 58, 9.1–9.23,
https://doi.org/10.1175/AMSMONOGRAPHS-D-16-0011.1, 2017. a
Bharadwaj, N., Matthews, A., Nelson, D., Lindenmaier, I., Isom, B., Hardin, J.,
and Johnson, K.: Atmospheric Radiation Measurement (ARM) user facility,
updated hourly, Ka ARM Zenith Radar (KAZRSPECCMASKGECOPOL), 2014-02-02 to
2014-02-03, ARM Mobile Facility (TMP) U. of Helsinki Research Station (SMEAR
II), Hyytiala, Finland; AMF2 (M1), https://doi.org/10.5439/1025218,
2014. a
Bühl, J., Seifert, P., Myagkov, A., and Ansmann, A.: Measuring ice- and liquid-water properties in mixed-phase cloud layers at the Leipzig Cloudnet station, Atmos. Chem. Phys., 16, 10609–10620, https://doi.org/10.5194/acp-16-10609-2016, 2016. a, b
Bühl, J., Alexander, S., Crewell, S., Heymsfield, A., Kalesse, H., Khain, A.,
Maahn, M., Van Tricht, K., and Wendisch, M.: Remote Sensing, Meteor.
Mon., 58, 10.1–10.21, https://doi.org/10.1175/AMSMONOGRAPHS-D-16-0015.1, 2017. a
Carter, D. A., Gage, K. S., Ecklund, W. L., Angevine, W. M., Johnston, P. E.,
Riddle, A. C., Wilson, J., and Williams, C. R.: Developments in UHF lower
tropospheric wind profiling at NOAA's Aeronomy Laboratory, Radio Sci., 30,
977–1001, https://doi.org/10.1029/95RS00649, 1995. a
Clothiaux, E. E., Ackerman, T. P., Mace, G. G., Moran, K. P., Marchand, R. T.,
Miller, M. A., and Martner, B. E.: Objective Determination of Cloud Heights
and Radar Reflectivities Using a Combination of Active Remote Sensors at the
ARM CART Sites, J. Appl. Meteorol., 39, 645–665,
https://doi.org/10.1175/1520-0450(2000)039<0645:ODOCHA>2.0.CO;2, 2000. a, b
Doviak, R. J. and Zrnic, D. S.: Doppler Radar & Weather Observations,
Courier Corporation, Academic Press, San Diego, https://doi.org/10.1016/C2009-0-22358-0, 1993. a
Engelmann, R., Kanitz, T., Baars, H., Heese, B., Althausen, D., Skupin, A., Wandinger, U., Komppula, M., Stachlewska, I. S., Amiridis, V., Marinou, E., Mattis, I., Linné, H., and Ansmann, A.: The automated multiwavelength Raman polarization and water-vapor lidar PollyXT: the neXT generation, Atmos. Meas. Tech., 9, 1767–1784, https://doi.org/10.5194/amt-9-1767-2016, 2016. a
Fan, J., Ghan, S., Ovchinnikov, M., Liu, X., Rasch, P. J., and Korolev, A.:
Representation of Arctic mixed-phase clouds and the
Wegener-Bergeron-Findeisen process in climate models: Perspectives from a
cloud-resolving study, J. Geophys. Res.-Atmos., 116, D1,
https://doi.org/10.1029/2010JD015375, 2011. a
Frisch, A. S., Fairall, C. W., and Snider, J. B.: Measurement of Stratus Cloud
and Drizzle Parameters in ASTEX with a Ka-Band Doppler Radar and a Microwave
Radiometer, J. Atmos. Sci., 52, 2788–2799,
https://doi.org/10.1175/1520-0469(1995)052<2788:MOSCAD>2.0.CO;2, 1995. a, b
Fukao, S. and Hamazu, K.: Radar for Meteorological and Atmospheric
Observations, Springer, Tokyo, https://doi.org/10.1007/978-4-431-54334-3, 2014. a
Garnier, R. and Taylor, J.: Discrete Mathematics: Proofs, Structures and
Applications, Third Edition, CRC Press, Hoboken, 2009. a
Görsdorf, U., Lehmann, V., Bauer-Pfundstein, M., Peters, G., Vavriv, D.,
Vinogradov, V., and Volkov, V.: A 35-GHz Polarimetric Doppler Radar for
Long-Term Observations of Cloud Parameters – Description of System and Data
Processing, J. Atmos. Ocean. Tech., 32, 675–690,
https://doi.org/10.1175/JTECH-D-14-00066.1, 2015. a, b, c
Hogan, R. J., Mittermaier, M. P., and Illingworth, A. J.: The Retrieval of Ice
Water Content from Radar Reflectivity Factor and Temperature and Its Use in
Evaluating a Mesoscale Model, J. Appl. Meteorol. Climatol.,
45, 301–317, https://doi.org/10.1175/JAM2340.1, 2006. a, b
Illingworth, A. J., Hogan, R. J., O'Connor, E. J., Bouniol, D., Delanoë,
J., Pelon, J., Protat, A., Brooks, M. E., Gaussiat, N., Wilson, D. R.,
Donovan, D. P., Baltink, H. K., van Zadelhoff, G.-J., Eastment, J. D.,
Goddard, J. W. F., Wrench, C. L., Haeffelin, M., Krasnov, O. A.,
Russchenberg, H. W. J., Piriou, J.-M., Vinit, F., Seifert, A., Tompkins,
A. M., and Willén, U.: Cloudnet: Continuous Evaluation of Cloud
Profiles in Seven Operational Models Using Ground-Based
Observations, B. Am. Meteorol. Soc., 88,
883–898, https://doi.org/10.1175/BAMS-88-6-883, 2007. a
Kalesse, H., Szyrmer, W., Kneifel, S., Kollias, P., and Luke, E.: Fingerprints of a riming event on cloud radar Doppler spectra: observations and modeling, Atmos. Chem. Phys., 16, 2997–3012, https://doi.org/10.5194/acp-16-2997-2016, 2016. a, b, c, d
Klepp, C., Michel, S., Protat, A., Burdanowitz, J., Albern, N., Kähnert, M.,
Dahl, A., Louf, V., Bakan, S., and Buehler, S. A.: OceanRAIN, a new in-situ
shipboard global ocean surface-reference dataset of all water cycle
components, Sci. Data, 5, 180122, https://doi.org/10.1038/sdata.2018.122, 2018. a
Kogan, Z. N., Mechem, D. B., and Kogan, Y. L.: Assessment of variability in
continental low stratiform clouds based on observations of radar
reflectivity, J. Geophys. Res.-Atmos., 110, D18,
https://doi.org/10.1029/2005JD006158, 2005. a
Kollias, P., Clothiaux, E. E., Miller, M. A., Albrecht, B. A., Stephens, G. L.,
and Ackerman, T. P.: Millimeter-Wavelength Radars: New Frontier in
Atmospheric Cloud and Precipitation Research, B.
Am. Meteor. Soc., 88, 1608–1624,
https://doi.org/10.1175/BAMS-88-10-1608, 2007a. a
Kollias, P., Miller, M. A., Luke, E. P., Johnson, K. L., Clothiaux, E. E.,
Moran, K. P., Widener, K. B., and Albrecht, B. A.: The Atmospheric Radiation
Measurement Program Cloud Profiling Radars: Second-Generation Sampling
Strategies, Processing, and Cloud Data Products, J. Atmos.
Ocean. Tech., 24, 1199–1214, https://doi.org/10.1175/JTECH2033.1,
2007b. a
Kollias, P., Clothiaux, E. E., Ackerman, T. P., Albrecht, B. A., Widener,
K. B., Moran, K. P., Luke, E. P., Johnson, K. L., Bharadwaj, N., Mead, J. B.,
Miller, M. A., Verlinde, J., Marchand, R. T., and Mace, G. G.: Development
and Applications of ARM Millimeter-Wavelength Cloud Radars, Meteor.
Mon., 57, 17.1–17.19, https://doi.org/10.1175/AMSMONOGRAPHS-D-15-0037.1, 2016. a, b
Korolev, A., McFarquhar, G., Field, P. R., Franklin, C., Lawson, P., Wang, Z.,
Williams, E., Abel, S. J., Axisa, D., Borrmann, S., Crosier, J., Fugal, J.,
Krämer, M., Lohmann, U., Schlenczek, O., Schnaiter, M., and Wendisch, M.:
Mixed-Phase Clouds: Progress and Challenges, Meteor. Mon., 58,
5.1–5.50, https://doi.org/10.1175/AMSMONOGRAPHS-D-17-0001.1, 2017. a
Luke, E. P. and Kollias, P.: Separating Cloud and Drizzle Radar Moments
during Precipitation Onset Using Doppler Spectra, J.
Atmos. Ocean. Tech., 30, 1656–1671,
https://doi.org/10.1175/JTECH-D-11-00195.1, 2013. a
Luke, E. P., Kollias, P., Johnson, K. L., and Clothiaux, E. E.: A Technique for
the Automatic Detection of Insect Clutter in Cloud Radar Returns, J.
Atmos. Ocean. Tech., 25, 1498–1513,
https://doi.org/10.1175/2007JTECHA953.1, 2008. a
Luke, E. P., Kollias, P., and Shupe, M. D.: Detection of supercooled liquid in
mixed-phase clouds using radar Doppler spectra, J. Geophys.
Res., 115, D19, https://doi.org/10.1029/2009JD012884, 2010. a, b
Maahn, M. and Löhnert, U.: Potential of Higher-Order Moments and Slopes of the
Radar Doppler Spectrum for Retrieving Microphysical and Kinematic Properties
of Arctic Ice Clouds, J. Appl. Meteorol. Climatol., 56,
263–282, https://doi.org/10.1175/JAMC-D-16-0020.1, 2017. a
Matrosov, S. Y. and Kropfli, R. A.: Cirrus Cloud Studies with Elliptically
Polarized Ka-band Radar Signals: A Suggested Approach, J. Atmos.
Ocean. Tech., 10, 684–692,
https://doi.org/10.1175/1520-0426(1993)010<0684:CCSWEP>2.0.CO;2, 1993. a
Myagkov, A., Seifert, P., Wandinger, U., Bauer-Pfundstein, M., and Matrosov,
S. Y.: Effects of Antenna Patterns on Cloud Radar Polarimetric Measurements,
J. Atmos. Ocean. Tech., 32, 1813–1828,
https://doi.org/10.1175/JTECH-D-15-0045.1, 2015. a
Myagkov, A., Seifert, P., Wandinger, U., Bühl, J., and Engelmann, R.: Relationship between temperature and apparent shape of pristine ice crystals derived from polarimetric cloud radar observations during the ACCEPT campaign, Atmos. Meas. Tech., 9, 3739–3754, https://doi.org/10.5194/amt-9-3739-2016, 2016. a, b
Oue, M., Kollias, P., Ryzhkov, A., and Luke, E. P.: Toward Exploring the
Synergy Between Cloud Radar Polarimetry and Doppler Spectral Analysis in Deep
Cold Precipitating Systems in the Arctic, J. Geophys. Res.-Atmos., 123, 2797–2815, https://doi.org/10.1002/2017JD027717, 2018. a, b, c, d
Petäjä, T., O’Connor, E. J., Moisseev, D., Sinclair, V. A., Manninen,
A. J., Väänänen, R., von Lerber, A., Thornton, J. A., Nicoll, K.,
Petersen, W., Chandrasekar, V., Smith, J. N., Winkler, P. M., Krüger, O.,
Hakola, H., Timonen, H., Brus, D., Laurila, T., Asmi, E., Riekkola, M.-L.,
Mona, L., Massoli, P., Engelmann, R., Komppula, M., Wang, J., Kuang, C.,
Bäck, J., Virtanen, A., Levula, J., Ritsche, M., and Hickmon, N.: BAECC: A
Field Campaign to Elucidate the Impact of Biogenic Aerosols on Clouds and
Climate, B. Am. Meteor. Soc., 97, 1909–1928,
https://doi.org/10.1175/BAMS-D-14-00199.1, 2016. a
Pfitzenmaier, L., Dufournet, Y., Unal, C. M. H., and Russchenberg, H. W. J.:
Retrieving Fall Streaks within Cloud Systems Using Doppler Radar, J.
Atmos. Ocean. Tech., 34, 905–920,
https://doi.org/10.1175/JTECH-D-16-0117.1, 2017. a
Radenz, M., Bühl, J., Lehmann, V., Görsdorf, U., and Leinweber, R.: Combining cloud radar and radar wind profiler for a value added estimate of vertical air motion and particle terminal velocity within clouds, Atmos. Meas. Tech., 11, 5925–5940, https://doi.org/10.5194/amt-11-5925-2018, 2018. a
Radenz, M., Bühl, J., and Seifert, P.: peakTree version of Aug2019,
https://doi.org/10.5281/zenodo.2577387, 2019. a
Rambukkange, M. P., Verlinde, J., Eloranta, E. W., Flynn, C. J., and Clothiaux,
E. E.: Using Doppler Spectra to Separate Hydrometeor Populations
and Analyze Ice Precipitation in Multilayered Mixed-Phase
Clouds, IEEE Geosci. Remote Sens. Lett., 8, 108–112,
https://doi.org/10.1109/LGRS.2010.2052781, 2011. a, b, c
Schmithüsen, H.: Upper air soundings during POLARSTERN cruise PS106.2
(ARK-XXXI/1.2), https://doi.org/10.1594/PANGAEA.882843, 2017. a, b, c
Shupe, M. D., Uttal, T., Matrosov, S. Y., and Frisch, A. S.: Cloud water
contents and hydrometeor sizes during the FIRE Arctic Clouds Experiment,
J. Geophys. Res.-Atmos., 106, 15015–15028,
https://doi.org/10.1029/2000JD900476, 2001. a
Shupe, M. D., Kollias, P., Matrosov, S. Y., and Schneider, T. L.: Deriving
Mixed-Phase Cloud Properties from Doppler Radar Spectra,
J. Atmos. Ocean. Tech., 21, 660–670,
https://doi.org/10.1175/1520-0426(2004)021<0660:DMCPFD>2.0.CO;2, 2004. a, b, c, d
Shupe, M. D., Comstock, J. M., Turner, D. D., and Mace, G. G.: Cloud Property
Retrievals in the ARM Program, Meteor. Mon., 57, 19.1–19.20,
https://doi.org/10.1175/AMSMONOGRAPHS-D-15-0030.1, 2016. a
Verlinde, J., Rambukkange, M. P., Clothiaux, E. E., McFarquhar, G. M., and
Eloranta, E. W.: Arctic multilayered, mixed-phase cloud processes revealed in
millimeter-wave cloud radar Doppler spectra, J. Geophys.
Res.-Atmos., 118, 199–213, https://doi.org/10.1002/2013JD020183, 2013. a
Wakasugi, K., Mizutano, M., Matsuo, M., Fukao, S., and Kato, S.: A direct
method of deriving drop size distribution and vertical air velocities from
VHF Doppler radar spectra, J. Atmos. Ocean. Tech.,
3, 623–629, https://doi.org/10.1175/1520-0426(1986)003<0623:ADMFDD>2.0.CO;2, 1986. a
Wang, Z. and Sassen, K.: Cirrus Cloud Microphysical Property Retrieval Using
Lidar and Radar Measurements, Part I: Algorithm Description and Comparison
with In Situ Data, J. Appl. Meteorol., 41, 218–229,
https://doi.org/10.1175/1520-0450(2002)041<0218:CCMPRU>2.0.CO;2, 2002. a
Wang, Z., Sassen, K., Whiteman, D. N., and Demoz, B. B.: Studying Altocumulus
with Ice Virga Using Ground-Based Active and Passive Remote Sensors, J.
Appl. Meteorol., 43, 449–460,
https://doi.org/10.1175/1520-0450(2004)043<0449:SAWIVU>2.0.CO;2, 2004.
a
Wendisch, M., Macke, A., Ehrlich, A., Lüpkes, C., Mech, M., Chechin, D.,
Dethloff, K., Barientos, C., Bozem, H., Brückner, M., Clemen, H.-C.,
Crewell, S., Donth, T., Dupuy, R., Ebell, K., Egerer, U., Engelmann, R.,
Engler, C., Eppers, O., Gehrmann, M., Gong, X., Gottschalk, M., Gourbeyre,
C., Griesche, H., Hartmann, J., Hartmann, M., Heinold, B., Herber, A.,
Herrmann, H., Heygster, G., Hoor, P., Jafariserajehlou, S., Jäkel, E.,
Järvinen, E., Jourdan, O., Kästner, U., Kecorius, S., Knudsen, E. M.,
Köllner, F., Kretzschmar, J., Lelli, L., Leroy, D., Maturilli, M., Mei, L.,
Mertes, S., Mioche, G., Neuber, R., Nicolaus, M., Nomokonova, T., Notholt,
J., Palm, M., van Pinxteren, M., Quaas, J., Richter, P., Ruiz-Donoso, E.,
Schäfer, M., Schmieder, K., Schnaiter, M., Schneider, J., Schwarzenböck,
A., Seifert, P., Shupe, M. D., Siebert, H., Spreen, G., Stapf, J., Stratmann,
F., Vogl, T., Welti, A., Wex, H., Wiedensohler, A., Zanatta, M., and
Zeppenfeld, S.: The Arctic Cloud Puzzle: Using ACLOUD/PASCAL Multi-Platform
Observations to Unravel the Role of Clouds and Aerosol Particles in Arctic
Amplification, B. Am. Meteor. Soc., 100,
841–871, https://doi.org/10.1175/BAMS-D-18-0072.1, 2019. a
Williams, C. R., Maahn, M., Hardin, J. C., and de Boer, G.: Clutter mitigation, multiple peaks, and high-order spectral moments in 35 GHz vertically pointing radar velocity spectra, Atmos. Meas. Tech., 11, 4963–4980, https://doi.org/10.5194/amt-11-4963-2018, 2018. a, b
Yu, G., Verlinde, J., Clothiaux, E. E., and Chen, Y.-S.: Mixed-phase cloud
phase partitioning using millimeter wavelength cloud radar Doppler velocity
spectra, J. Geophys. Res.-Atmos., 119, 7556–7576,
https://doi.org/10.1002/2013JD021182, 2014. a, b, c, d
Zhao, C., Xie, S., Klein, S. A., Protat, A., Shupe, M. D., McFarlane, S. A.,
Comstock, J. M., Delanoë, J., Deng, M., Dunn, M., Hogan, R. J., Huang, D.,
Jensen, M. P., Mace, G. G., McCoy, R., O'Connor, E. J., Turner, D. D., and
Wang, Z.: Toward understanding of differences in current cloud retrievals of
ARM ground-based measurements, J. Geophys. Res.-Atmos.,
117, D10, https://doi.org/10.1029/2011JD016792, 2012. a
Short summary
Clouds may be composed of more than one particle population even at the smallest scales. Cloud radar observations can contain information on multiple particle species, showing up as distinct peaks and subpeaks in the Doppler spectrum. We propose the use of binary tree structures to recursively structure these peaks. Two case studies from different locations and instruments illustrate how this approach can be used to disentangle particle populations in multilayered mixed-phase clouds.
Clouds may be composed of more than one particle population even at the smallest scales. Cloud...
