Articles | Volume 8, issue 3
09 Mar 2015
Research article | 09 Mar 2015
Upper-troposphere and lower-stratosphere water vapor retrievals from the 1400 and 1900 nm water vapor bands
B. C. Kindel et al.
No articles found.
Steffen Mauceri, Steven Massie, and Sebastian Schmidt
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
The Orbiting Carbon Observatory-2 makes space-based measurements of reflected sun light. Using a retrieval algorithm these measurements are converted to CO2 concentrations in the atmosphere. However, the converted CO2 concentrations contain errors for observations close to clouds. Using a simple machine learning approach, we developed a model to correct these remaining errors. The model is able to reduce errors over land and ocean by 31 % and 55 %, respectively.
Hong Chen, Sebastian Schmidt, Steven T. Massie, Vikas Nataraja, Matthew S. Norgren, Jake J. Gristey, Graham Feingold, Robert E. Holz, and Hironobu Iwabuchi
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
We introduce the Education and Research 3D Radiative Transfer Toolbox (EaR3T) for quantifying and mitigating artifacts in atmospheric radiation science algorithms due to spatially inhomogeneous clouds and surfaces, and show the benefits of automated, realistic radiance and irradiance generation along extended satellite orbits, flight tracks from entire aircraft field missions, and synthetic data generation from model data.
Dongwei Fu, Larry Di Girolamo, Robert M. Rauber, Greg M. McFarquhar, Stephen W. Nesbitt, Jesse Loveridge, Yulan Hong, Bastiaan van Diedenhoven, Brian Cairns, Mikhail D. Alexandrov, Paul Lawson, Sarah Woods, Simone Tanelli, Sebastian Schmidt, Chris Hostetler, and Amy Jo Scarino
Atmos. Chem. Phys., 22, 8259–8285,Short summary
Satellite-retrieved cloud microphysics are widely used in climate research because of their central role in water and energy cycles. Here, we provide the first detailed investigation of retrieved cloud drop sizes from in situ and various satellite and airborne remote sensing techniques applied to real cumulus cloud fields. We conclude that the most widely used passive remote sensing method employed in climate research produces high biases of 6–8 µm (60 %–80 %) caused by 3-D radiative effects.
Youhua Tang, Patrick Campbell, Pius Lee, Rick Saylor, Fanglin Yang, Barry Baker, Daniel Tong, Ariel Stein, Jianping Huang, Ho-Chun Huang, Li Pan, Jeff McQueen, Ivanka Stajner, Jose Tirado-Delgado, Youngsun Jung, Melissa Yang, Ilann Bourgeois, Jeff Peischl, Tom Ryerson, Donald Blake, Joshua Schwarz, Jose-Luis Jimenez, James Crawford, Glenn Diskin, Richard Moore, Johnathan Hair, Greg Huey, Andrew Rollins, Jack Dibb, and Xiaoyang Zhang
This paper compared two meteorological data for driving the regional air quality model: a regional meteorological modelling using WRF (WRF-CMAQ), and the direct interpolation from an operational global model (GFS-CMAQ). In the comparison with surface measurements and aircraft data in summer 2019, these two methods have mixed performance depending on the corresponding meteorological settings and performances. The direct interpolation is a viable method to drive air quality models.
Nicole A. June, Anna L. Hodshire, Elizabeth B. Wiggins, Edward L. Winstead, Claire E. Robinson, K. Lee Thornhill, Kevin J. Sanchez, Richard H. Moore, Demetrios Pagonis, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Matthew M. Coggon, Jonathan M. Dean-Day, T. Paul Bui, Jeff Peischl, Robert J. Yokelson, Matthew J. Alvarado, Sonia M. Kreidenweis, Shantanu H. Jathar, and Jeffrey R. Pierce
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
The evolution of organic aerosol composition and size is uncertain due to variability within and between smoke plumes. We examine the impact of plume concentration on smoke evolution from smoke plumes sampled by the NASA DC-8 during FIREX-AQ. We find that observed organic aerosol and size distribution changes are correlated to plume aerosol mass concentrations. Additionally, coagulation explains the majority of the observed growth.
Pamela Rickly, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Glenn M. Wolfe, Ryan Bennett, Ilann Bourgeois, John D. Crounse, Jack E. Dibb, Joshua P. DiGangi, Glenn S. Diskin, Maximilian Dollner, Emily M. Gargulinski, Samuel R. Hall, Hannah S. Halliday, Thomas F. Hanisco, Reem A. Hannun, Jin Liao, Richard Moore, Benjamin A. Nault, John B. Nowak, Claire E. Robinson, Thomas Ryerson, Kevin J. Sanchez, Manuel Schöberl, Amber J. Soja, Jason M. St. Clair, Kenneth L. Thornhill, Kirk Ullmann, Paul O. Wennberg, Bernadett Weinzierl, Elizabeth B. Wiggins, Edward L. Winstead, and Andrew W. Rollins
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Biomass burning sulfur dioxide (SO2) emission factors range from 0.27–1.1 g kg-1 C. Biomass burning SO2 can quickly form sulfate and organosulfur, but these pathways are dependent on liquid water content and pH. Hydroxymethanesulfonate (HMS) appears to be directly emitted from some fire sources, but is not the sole contributor to the organosulfur signal. It is shown that HMS and organosulfur chemistry may be an important S(IV) reservoir with the fate dependent on the surrounding conditions.
Glenn M. Wolfe, Thomas F. Hanisco, Heather L. Arkinson, Donald R. Blake, Armin Wisthaler, Tomas Mikoviny, Thomas B. Ryerson, Ilana Pollack, Jeff Peischl, Paul O. Wennberg, John D. Crounse, Jason M. St. Clair, Alex Teng, L. Gregory Huey, Xiaoxi Liu, Alan Fried, Petter Weibring, Dirk Richter, James Walega, Samuel R. Hall, Kirk Ullmann, Jose L. Jimenez, Pedro Campuzano-Jost, T. Paul Bui, Glenn Diskin, James R. Podolske, Glen Sachse, and Ronald C. Cohen
Atmos. Chem. Phys., 22, 4253–4275,Short summary
Smoke plumes are chemically complex. This work combines airborne observations of smoke plume composition with a photochemical model to probe the production of ozone and the fate of reactive gases in the outflow of a large wildfire. Model–measurement comparisons illustrate how uncertain emissions and chemical processes propagate into simulated chemical evolution. Results provide insight into how this system responds to perturbations, which can help guide future observation and modeling efforts.
Paul Alan Barrett, Steven J. Abel, Hugh Coe, Ian Crawford, Amie Dobracki, James M. Haywood, Steve Howell, Anthony Jones, Justin Langridge, Greg McFarquhar, Graeme Nott, Hannah Price, Jens Redemann, Yohei Shinozuka, Kate Szpek, Jonathan Taylor, Robert Wood, Huihui Wu, Paquita Zuidema, Stephane Bauguitte, Ryan Bennett, Keith Bower, Hong Chen, Sabrina P. Cochrane, Michael Cotterell, Nicholas Davies, David Delene, Connor Flynn, Andrew Freedman, Steffen Freitag, Siddhant Gupta, David Noone, Timothy B. Onasch, James Podolske, Michael R. Poellot, Sebastian K. Schmidt, Stephen Springston, Arthur J. Sedlacek III, Jamie Trembath, Alan Vance, Maria Zawadowicz, and Jianhao Zhang
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
In order to better understand weather and climate it is vital to go into the field and collect observations. Often measurements take place in isolation but here we compared data from two aircraft and one ground-based site. This was done in order to understand how well measurements made on one platform compared to those made on another. Whilst this is easy to do in a controlled laboratory setting it is more challenging in the real-world and so these comparisons are as valuable as they are rare.
Matthew S. Norgren, John Wood, K. Sebastian Schmidt, Bastiaan van Diedenhoven, Snorre A. Stamnes, Luke D. Ziemba, Ewan C. Crosbie, Michael A. Shook, A. Scott Kittelman, Samuel E. LeBlanc, Stephen Broccardo, Steffen Freitag, and Jeffrey S. Reid
Atmos. Meas. Tech., 15, 1373–1394,Short summary
A new spectral instrument (SPN-S), with the ability to partition solar radiation into direct and diffuse components, is used in airborne settings to study the optical properties of aerosols and cirrus. It is a low-cost and mechanically simple system but has higher measurement uncertainty than existing standards. This challenge is overcome by utilizing the unique measurement capabilities to develop new retrieval techniques. Validation is done with data from two NASA airborne research campaigns.
Martin Breitenlechner, Gordon A. Novak, J. Andrew Neuman, Andrew W. Rollins, and Patrick R. Veres
Atmos. Meas. Tech., 15, 1159–1169,Short summary
We coupled a new ion source to a commercially available state-of-the-art trace gas analyzer. The instrument is particularly well suited for conducting high-altitude observations, addressing the challenges of low ambient pressures and a complex sample matrix. The new instrument and ion source provides significant advantages to more traditional modes of operation, without sacrificing the sensitivity and flexibility of this technique.
Vikas Nataraja, Sebastian Schmidt, Hong Chen, Takanobu Yamaguchi, Jan Kazil, Graham Feingold, Kevin Wolf, and Hironobu Iwabuchi
Atmos. Meas. Tech. Discuss.,
Revised manuscript under review for AMTShort summary
A Convolutional Neural Network (CNN) is introduced to retrieve Cloud Optical Thickness (COT) from passive cloud imagery. The CNN, trained on Large Eddy Simulations from the Sulu Sea, learns from spatial information at multiple scales to reduce cloud inhomogeneity effects. By considering the spatial context of a pixel, the CNN outperforms the traditional Independent Pixel Approximation (IPA) across several cloud morphology metrics.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Michal Segal Rozenhaimer, Meloë Kacenelenbogen, Yohei Shinozuka, Connor Flynn, Rich Ferrare, Sharon Burton, Chris Hostetler, Marc Mallet, and Paquita Zuidema
Atmos. Meas. Tech., 15, 61–77,Short summary
This work presents heating rates derived from aircraft observations from the 2016 and 2017 field campaigns of ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS). We separate the total heating rates into aerosol and gas (primarily water vapor) absorption and explore some of the co-variability of heating rate profiles and their primary drivers, leading to the development of a new concept: the heating rate efficiency (HRE; the heating rate per unit aerosol extinction).
Ilann Bourgeois, Jeff Peischl, J. Andrew Neuman, Steven S. Brown, Hannah M. Allen, Pedro Campuzano-Jost, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Jessica B. Gilman, Georgios I. Gkatzelis, Hongyu Guo, Hannah Halliday, Thomas F. Hanisco, Christopher D. Holmes, L. Gregory Huey, Jose L. Jimenez, Aaron D. Lamplugh, Young Ro Lee, Jakob Lindaas, Richard H. Moore, John B. Nowak, Demetrios Pagonis, Pamela S. Rickly, Michael A. Robinson, Andrew W. Rollins, Vanessa Selimovic, Jason M. St. Clair, David Tanner, Krystal T. Vasquez, Patrick R. Veres, Carsten Warneke, Paul O. Wennberg, Rebecca A. Washenfelder, Elizabeth B. Wiggins, Caroline C. Womack, Lu Xu, Kyle J. Zarzana, and Thomas B. Ryerson
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
Understanding fire emission impacts on the atmosphere is key to effective air quality management and requires accurate measurements. We present a comparison of airborne measurements of key atmospheric species in ambient air and in fire smoke. We show that most instruments performed within instrument uncertainties. In some cases, further work is needed to fully characterize instrument performance. Comparing independent measurements using different techniques is important to assess their accuracy.
Debora Griffin, Chris A. McLinden, Enrico Dammers, Cristen Adams, Chelsea E. Stockwell, Carsten Warneke, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Kyle J. Zarzana, Jake P. Rowe, Rainer Volkamer, Christoph Knote, Natalie Kille, Theodore K. Koenig, Christopher F. Lee, Drew Rollins, Pamela S. Rickly, Jack Chen, Lukas Fehr, Adam Bourassa, Doug Degenstein, Katherine Hayden, Cristian Mihele, Sumi N. Wren, John Liggio, Ayodeji Akingunola, and Paul Makar
Atmos. Meas. Tech., 14, 7929–7957,Short summary
Satellite-derived NOx emissions from biomass burning are estimated with TROPOMI observations. Two common emission estimation methods are applied, and sensitivity tests with model output were performed to determine the accuracy of these methods. The effect of smoke aerosols on TROPOMI NO2 columns is estimated and compared to aircraft observations from four different aircraft campaigns measuring biomass burning plumes in 2018 and 2019 in North America.
Zachary C. J. Decker, Michael A. Robinson, Kelley C. Barsanti, Ilann Bourgeois, Matthew M. Coggon, Joshua P. DiGangi, Glenn S. Diskin, Frank M. Flocke, Alessandro Franchin, Carley D. Fredrickson, Georgios I. Gkatzelis, Samuel R. Hall, Hannah Halliday, Christopher D. Holmes, L. Gregory Huey, Young Ro Lee, Jakob Lindaas, Ann M. Middlebrook, Denise D. Montzka, Richard Moore, J. Andrew Neuman, John B. Nowak, Brett B. Palm, Jeff Peischl, Felix Piel, Pamela S. Rickly, Andrew W. Rollins, Thomas B. Ryerson, Rebecca H. Schwantes, Kanako Sekimoto, Lee Thornhill, Joel A. Thornton, Geoffrey S. Tyndall, Kirk Ullmann, Paul Van Rooy, Patrick R. Veres, Carsten Warneke, Rebecca A. Washenfelder, Andrew J. Weinheimer, Elizabeth Wiggins, Edward Winstead, Armin Wisthaler, Caroline Womack, and Steven S. Brown
Atmos. Chem. Phys., 21, 16293–16317,Short summary
To understand air quality impacts from wildfires, we need an accurate picture of how wildfire smoke changes chemically both day and night as sunlight changes the chemistry of smoke. We present a chemical analysis of wildfire smoke as it changes from midday through the night. We use aircraft observations from the FIREX-AQ field campaign with a chemical box model. We find that even under sunlight typical
nighttimechemistry thrives and controls the fate of key smoke plume chemical processes.
Eric J. Hintsa, Fred L. Moore, Dale F. Hurst, Geoff S. Dutton, Bradley D. Hall, J. David Nance, Ben R. Miller, Stephen A. Montzka, Laura P. Wolton, Audra McClure-Begley, James W. Elkins, Emrys G. Hall, Allen F. Jordan, Andrew W. Rollins, Troy D. Thornberry, Laurel A. Watts, Chelsea R. Thompson, Jeff Peischl, Ilann Bourgeois, Thomas B. Ryerson, Bruce C. Daube, Yenny Gonzalez Ramos, Roisin Commane, Gregory W. Santoni, Jasna V. Pittman, Steven C. Wofsy, Eric Kort, Glenn S. Diskin, and T. Paul Bui
Atmos. Meas. Tech., 14, 6795–6819,Short summary
We built UCATS to study atmospheric chemistry and transport. It has measured trace gases including CFCs, N2O, SF6, CH4, CO, and H2 with gas chromatography, as well as ozone and water vapor. UCATS has been part of missions to study the tropical tropopause; transport of air into the stratosphere; greenhouse gases, transport, and chemistry in the troposphere; and ozone chemistry, on both piloted and unmanned aircraft. Its design, capabilities, and some results are shown and described here.
Charles A. Brock, Karl D. Froyd, Maximilian Dollner, Christina J. Williamson, Gregory Schill, Daniel M. Murphy, Nicholas J. Wagner, Agnieszka Kupc, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Douglas A. Day, Derek J. Price, Bernadett Weinzierl, Joshua P. Schwarz, Joseph M. Katich, Siyuan Wang, Linghan Zeng, Rodney Weber, Jack Dibb, Eric Scheuer, Glenn S. Diskin, Joshua P. DiGangi, ThaoPaul Bui, Jonathan M. Dean-Day, Chelsea R. Thompson, Jeff Peischl, Thomas B. Ryerson, Ilann Bourgeois, Bruce C. Daube, Róisín Commane, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 15023–15063,Short summary
The Atmospheric Tomography Mission was an airborne study that mapped the chemical composition of the remote atmosphere. From this, we developed a comprehensive description of aerosol properties that provides a unique, global-scale dataset against which models can be compared. The data show the polluted nature of the remote atmosphere in the Northern Hemisphere and quantify the contributions of sea salt, dust, soot, biomass burning particles, and pollution particles to the haziness of the sky.
Christina J. Williamson, Agnieszka Kupc, Andrew Rollins, Jan Kazil, Karl D. Froyd, Eric A. Ray, Daniel M. Murphy, Gregory P. Schill, Jeff Peischl, Chelsea Thompson, Ilann Bourgeois, Thomas B. Ryerson, Glenn S. Diskin, Joshua P. DiGangi, Donald R. Blake, Thao Paul V. Bui, Maximilian Dollner, Bernadett Weinzierl, and Charles A. Brock
Atmos. Chem. Phys., 21, 9065–9088,Short summary
Aerosols in the stratosphere influence climate by scattering and absorbing sunlight and through chemical reactions occurring on the particles’ surfaces. We observed more nucleation mode aerosols (small aerosols, with diameters below 12 nm) in the mid- and high-latitude lowermost stratosphere (8–13 km) in the Northern Hemisphere (NH) than in the Southern Hemisphere. The most likely cause of this is aircraft emissions, which are concentrated in the NH at similar altitudes to our observations.
Hong Chen, Sebastian Schmidt, Michael D. King, Galina Wind, Anthony Bucholtz, Elizabeth A. Reid, Michal Segal-Rozenhaimer, William L. Smith, Patrick C. Taylor, Seiji Kato, and Peter Pilewskie
Atmos. Meas. Tech., 14, 2673–2697,Short summary
In this paper, we accessed the shortwave irradiance derived from MODIS cloud optical properties by using aircraft measurements. We developed a data aggregation technique to parameterize spectral surface albedo by snow fraction in the Arctic. We found that undetected clouds have the most significant impact on the imagery-derived irradiance. This study suggests that passive imagery cloud detection could be improved through a multi-pixel approach that would make it more dependable in the Arctic.
Ananth Ranjithkumar, Hamish Gordon, Christina Williamson, Andrew Rollins, Kirsty Pringle, Agnieszka Kupc, Nathan Luke Abraham, Charles Brock, and Ken Carslaw
Atmos. Chem. Phys., 21, 4979–5014,Short summary
The effect aerosols have on climate can be better understood by studying their vertical and spatial distribution throughout the atmosphere. We use observation data from the ATom campaign and evaluate the vertical profile of aerosol number concentration, sulfur dioxide and condensation sink using the UKESM (UK Earth System Model). We identify uncertainties in key atmospheric processes that help improve their theoretical representation in global climate models.
Pamela S. Rickly, Lu Xu, John D. Crounse, Paul O. Wennberg, and Andrew W. Rollins
Atmos. Meas. Tech., 14, 2429–2439,Short summary
Key improvements have been made to an in situ laser-induced fluorescence instrument for measuring SO2 in polluted and pristine environments. Laser linewidth is reduced, rapid laser tuning is implemented, and fluorescence bandpass filters are optimized. These improvements have led to a 50 % reduction in instrument detection limit. The influence of aromatic compounds was also investigated and determined to not bias SO2 measurements.
Steven T. Massie, Heather Cronk, Aronne Merrelli, Christopher O'Dell, K. Sebastian Schmidt, Hong Chen, and David Baker
Atmos. Meas. Tech., 14, 1475–1499,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.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563,Short summary
Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Amie Dobracki, Paquita Zuidema, Steven Howell, Steffen Freitag, and Sarah Doherty
Atmos. Meas. Tech., 14, 567–593,Short summary
Based on observations from the 2016 and 2017 field campaigns of ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS), this work establishes an observationally driven link from mid-visible aerosol optical depth (AOD) and other scene parameters to broadband shortwave irradiance (and by extension the direct aerosol radiative effect, DARE). The majority of the case-to-case DARE variability within the ORACLES dataset is attributable to the dependence on AOD and scene albedo.
Reem A. Hannun, Andrew K. Swanson, Steven A. Bailey, Thomas F. Hanisco, T. Paul Bui, Ilann Bourgeois, Jeff Peischl, and Thomas B. Ryerson
Atmos. Meas. Tech., 13, 6877–6887,Short summary
We have developed a cavity-enhanced absorption instrument to measure ozone in the atmosphere. The detection technique enables highly sensitive measurements in fast averaging times. The compact, robust instrument is suitable for operation in varied field environments, including aboard research aircraft. We have successfully flown the instrument and demonstrated its performance capabilities with measurements of ozone deposition rates over the coastal Pacific Ocean.
Agnieszka Kupc, Christina J. Williamson, Anna L. Hodshire, Jan Kazil, Eric Ray, T. Paul Bui, Maximilian Dollner, Karl D. Froyd, Kathryn McKain, Andrew Rollins, Gregory P. Schill, Alexander Thames, Bernadett B. Weinzierl, Jeffrey R. Pierce, and Charles A. Brock
Atmos. Chem. Phys., 20, 15037–15060,Short summary
Tropical upper troposphere over the Atlantic and Pacific oceans is a major source region of new particles. These particles are associated with the outflow from deep convection. We investigate the processes that govern the formation of these particles and their initial growth and show that none of the formation schemes commonly used in global models are consistent with observations. Using newer schemes indicates that organic compounds are likely important as nucleating and initial growth agents.
Melodie Lao, Leigh R. Crilley, Leyla Salehpoor, Teles C. Furlani, Ilann Bourgeois, J. Andrew Neuman, Andrew W. Rollins, Patrick R. Veres, Rebecca A. Washenfelder, Caroline C. Womack, Cora J. Young, and Trevor C. VandenBoer
Atmos. Meas. Tech., 13, 5873–5890,Short summary
Nitrous acid (HONO) is a key intermediate in the generation of oxidants and fate of nitrogen oxides in the atmosphere. High-purity calibration sources that produce stable atmospherically relevant levels under field conditions have not been made to date, reducing measurement accuracy. In this study a simple salt-coated tube humidified with water vapor is demonstrated to produce pure stable low levels of HONO, with modifications allowing the generation of higher amounts.
Martina Krämer, Christian Rolf, Nicole Spelten, Armin Afchine, David Fahey, Eric Jensen, Sergey Khaykin, Thomas Kuhn, Paul Lawson, Alexey Lykov, Laura L. Pan, Martin Riese, Andrew Rollins, Fred Stroh, Troy Thornberry, Veronika Wolf, Sarah Woods, Peter Spichtinger, Johannes Quaas, and Odran Sourdeval
Atmos. Chem. Phys., 20, 12569–12608,Short summary
To improve the representations of cirrus clouds in climate predictions, extended knowledge of their properties and geographical distribution is required. This study presents extensive airborne in situ and satellite remote sensing climatologies of cirrus and humidity, which serve as a guide to cirrus clouds. Further, exemplary radiative characteristics of cirrus types and also in situ observations of tropical tropopause layer cirrus and humidity in the Asian monsoon anticyclone are shown.
Yohei Shinozuka, Meloë S. Kacenelenbogen, Sharon P. Burton, Steven G. Howell, Paquita Zuidema, Richard A. Ferrare, Samuel E. LeBlanc, Kristina Pistone, Stephen Broccardo, Jens Redemann, K. Sebastian Schmidt, Sabrina P. Cochrane, Marta Fenn, Steffen Freitag, Amie Dobracki, Michal Segal-Rosenheimer, and Connor J. Flynn
Atmos. Chem. Phys., 20, 11275–11285,Short summary
To help satellite retrieval of aerosols and studies of their radiative effects, we demonstrate that daytime aerosol optical depth over low-level clouds is similar to that in neighboring clear skies at the same heights. Based on recent airborne lidar and sun photometer observations above the southeast Atlantic, the mean AOD difference at 532 nm is between 0 and -0.01, when comparing the cloudy and clear sides of cloud edges, with each up to 20 km wide.
Andrew W. Rollins, Pamela S. Rickly, Ru-Shan Gao, Thomas B. Ryerson, Steven S. Brown, Jeff Peischl, and Ilann Bourgeois
Atmos. Meas. Tech., 13, 2425–2439,Short summary
Nitric oxide (NO) is a key atmospheric constituent controlling atmospheric oxidation chemistry and tropospheric ozone formation. Existing instrumentation capable of quantifying NO at very low mixing ratios is uncommon and typically relies on chemiluminescence. We describe and demonstrate a new laser-based technique (LIF) with significant practical and technical advantages to CL. This technique is expected to allow for advances in understanding of atmospheric radical chemistry.
Antonio Spanu, Maximilian Dollner, Josef Gasteiger, T. Paul Bui, and Bernadett Weinzierl
Atmos. Meas. Tech., 13, 1963–1987,Short summary
This study investigates how the airflow around wing-mounted instruments on fast-flying aircraft affects aerosol and cloud measurements. It combines airborne data with numerical simulations and shows that particle speed, particle concentration, and shape of water droplets are modified by the airflow. The proposed correction strategy for optical particle counters and optical array probes considers airflow effects and significantly reduces errors of derived ambient aerosol and cloud properties.
Alexander B. Thames, William H. Brune, David O. Miller, Hannah M. Allen, Eric C. Apel, Donald R. Blake, T. Paul Bui, Roisin Commane, John D. Crounse, Bruce C. Daube, Glenn S. Diskin, Joshua P. DiGangi, James W. Elkins, Samuel R. Hall, Thomas F. Hanisco, Reem A. Hannun, Eric Hintsa, Rebecca S. Hornbrook, Michelle J. Kim, Kathryn McKain, Fred L. Moore, Julie M. Nicely, Jeffrey Peischl, Thomas B. Ryerson, Jason M. St. Clair, Colm Sweeney, Alex Teng, Chelsea R. Thompson, Kirk Ullmann, Paul O. Wennberg, and Glenn M. Wolfe
Atmos. Chem. Phys., 20, 4013–4029,Short summary
Oceans and the atmosphere exchange volatile gases that react with the hydroxyl radical (OH). During a NASA airborne study, measurements of the total frequency of OH reactions, called the OH reactivity, were made in the marine boundary layer of the Atlantic and Pacific oceans. The measured OH reactivity often exceeded the OH reactivity calculated from measured chemical species. This missing OH reactivity appears to be from unmeasured volatile organic compounds coming out of the ocean.
Rebecca H. Schwantes, Louisa K. Emmons, John J. Orlando, Mary C. Barth, Geoffrey S. Tyndall, Samuel R. Hall, Kirk Ullmann, Jason M. St. Clair, Donald R. Blake, Armin Wisthaler, and Thao Paul V. Bui
Atmos. Chem. Phys., 20, 3739–3776,Short summary
Ozone is a greenhouse gas and air pollutant that is harmful to human health and plants. During the summer in the southeastern US, many regional and global models are biased high for surface ozone compared to observations. Here adding more complex and updated chemistry for isoprene and terpenes, which are biogenic hydrocarbons emitted from trees and vegetation, into an earth system model greatly reduces the simulated surface ozone bias compared to aircraft and monitoring station data.
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Steven Platnick, Kerry Meyer, Rich Ferrare, Sharon Burton, Chris Hostetler, Steven Howell, Steffen Freitag, Amie Dobracki, and Sarah Doherty
Atmos. Meas. Tech., 12, 6505–6528,Short summary
For two cases from the NASA ORACLES experiments, we retrieve aerosol and cloud properties and calculate a direct aerosol radiative effect (DARE). We investigate the relationship between DARE and the cloud albedo by specifying the albedo for which DARE transitions from a cooling to warming radiative effect. Our new aerosol retrieval algorithm is successful despite complexities associated with scenes that contain aerosols above clouds and decreases the uncertainty on retrieved aerosol parameters.
Steffen Mauceri, Bruce Kindel, Steven Massie, and Peter Pilewskie
Atmos. Meas. Tech., 12, 6017–6036,Short summary
Aerosols are fine particles that are suspended in Earth’s atmosphere. A better understanding of aerosols is important to lower uncertainties in climate predictions. We propose measuring aerosols from satellites and airplanes equipped with hyperspectral cameras using an artificial neural network, a form of machine learning. We applied our neural network to hyperspectral observations from a recent airplane flight over India and find general agreement with independent aerosol measurements.
Jeffrey S. Reid, Derek J. Posselt, Kathleen Kaku, Robert A. Holz, Gao Chen, Edwin W. Eloranta, Ralph E. Kuehn, Sarah Woods, Jianglong Zhang, Bruce Anderson, T. Paul Bui, Glenn S. Diskin, Patrick Minnis, Michael J. Newchurch, Simone Tanelli, Charles R. Trepte, K. Lee Thornhill, and Luke D. Ziemba
Atmos. Chem. Phys., 19, 11413–11442,Short summary
The scientific community often focuses on the vertical transport of pollutants by clouds for those with bases at the planetary boundary layer (such as typical fair-weather cumulus) and the outflow from thunderstorms at their tops. We demonstrate complex aerosol and cloud features formed in mid-level thunderstorm outflow. These layers have strong relationships to mid-level tropospheric clouds, an important but difficult to model or monitor cloud regime for climate studies.
Huisheng Bian, Karl Froyd, Daniel M. Murphy, Jack Dibb, Anton Darmenov, Mian Chin, Peter R. Colarco, Arlindo da Silva, Tom L. Kucsera, Gregory Schill, Hongbin Yu, Paul Bui, Maximilian Dollner, Bernadett Weinzierl, and Alexander Smirnov
Atmos. Chem. Phys., 19, 10773–10785,Short summary
We address the GEOS-GOCART sea salt simulations constrained by NASA EVS ATom measurements, as well as those by MODIS and the AERONET MAN. The study covers remote regions over the Pacific, Atlantic, and Southern oceans from near the surface to ~ 12 km altitude and covers both summer and winter seasons. Important sea salt fields, e.g., mass mixing ratio, vertical distribution, size distribution, and marine aerosol AOD, as well as their relationship to relative humidity and emissions, are examined.
Kristina Pistone, Jens Redemann, Sarah Doherty, Paquita Zuidema, Sharon Burton, Brian Cairns, Sabrina Cochrane, Richard Ferrare, Connor Flynn, Steffen Freitag, Steven G. Howell, Meloë Kacenelenbogen, Samuel LeBlanc, Xu Liu, K. Sebastian Schmidt, Arthur J. Sedlacek III, Michal Segal-Rozenhaimer, Yohei Shinozuka, Snorre Stamnes, Bastiaan van Diedenhoven, Gerard Van Harten, and Feng Xu
Atmos. Chem. Phys., 19, 9181–9208,Short summary
Understanding how smoke particles interact with sunlight is important in calculating their effects on climate, since some smoke is more scattering (cooling) and some is more absorbing (heating). Knowing this proportion is important for both satellite observations and climate models. We measured smoke properties in a recent aircraft-based field campaign off the west coast of Africa and present a comparison of these properties as measured using the six different, independent techniques available.
Charles A. Brock, Christina Williamson, Agnieszka Kupc, Karl D. Froyd, Frank Erdesz, Nicholas Wagner, Matthews Richardson, Joshua P. Schwarz, Ru-Shan Gao, Joseph M. Katich, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Jose L. Jimenez, Bernadett Weinzierl, Maximilian Dollner, ThaoPaul Bui, and Daniel M. Murphy
Atmos. Meas. Tech., 12, 3081–3099,Short summary
From 2016 to 2018 a NASA aircraft profiled the atmosphere from 180 m to ~12 km from the Arctic to the Antarctic over both the Pacific and Atlantic oceans. This program, ATom, sought to sample atmospheric chemical composition to compare with global climate models. We describe the how measurements of particulate matter were made during ATom, and show that the instrument performance was excellent. Data from this project can be used with confidence to evaluate models and compare with satellites.
Ju-Mee Ryoo, Laura T. Iraci, Tomoaki Tanaka, Josette E. Marrero, Emma L. Yates, Inez Fung, Anna M. Michalak, Jovan Tadić, Warren Gore, T. Paul Bui, Jonathan M. Dean-Day, and Cecilia S. Chang
Atmos. Meas. Tech., 12, 2949–2966,Short summary
We designed cylindrical flights and computed the emission fluxes using a kriging method and Gauss's theorem over Sacramento, California. Differences in wind treatment and background affect the emission estimates by a factor of 1.5 to 7. The effects of the vertical layer average and the vertical mass transfer on the emission estimates are found to be small, esp. local scale. The result also suggests a closed-shape flight profile can better contain total emissions than a one-sided curtain flight.
Sabine Robrecht, Bärbel Vogel, Jens-Uwe Grooß, Karen Rosenlof, Troy Thornberry, Andrew Rollins, Martina Krämer, Lance Christensen, and Rolf Müller
Atmos. Chem. Phys., 19, 5805–5833,Short summary
The potential destruction of stratospheric ozone in the mid-latitudes has been discussed recently. We analysed this ozone loss mechanism and its sensitivities. In a certain temperature range, we found a threshold in water vapour, which has to be exceeded for ozone loss to occur. We show the dependence of this water vapour threshold on temperature, sulfate content and air composition. This study provides a basis to estimate the impact of potential sulphate geoengineering on stratospheric ozone.
Marc Mallet, Pierre Nabat, Paquita Zuidema, Jens Redemann, Andrew Mark Sayer, Martin Stengel, Sebastian Schmidt, Sabrina Cochrane, Sharon Burton, Richard Ferrare, Kerry Meyer, Pablo Saide, Hiren Jethva, Omar Torres, Robert Wood, David Saint Martin, Romain Roehrig, Christina Hsu, and Paola Formenti
Atmos. Chem. Phys., 19, 4963–4990,Short summary
The model is able to represent LWP but not the LCF. AOD is consistent over the continent but also over ocean (ACAOD). Differences are observed in SSA due to the absence of internal mixing in ALADIN-Climate. A significant regional gradient of the forcing at TOA is observed. An intense positive forcing is simulated over Gabon. Results highlight the significant effect of enhanced moisture on BBA extinction. The surface dimming modifies the energy budget.
Stefan Kaufmann, Christiane Voigt, Romy Heller, Tina Jurkat-Witschas, Martina Krämer, Christian Rolf, Martin Zöger, Andreas Giez, Bernhard Buchholz, Volker Ebert, Troy Thornberry, and Ulrich Schumann
Atmos. Chem. Phys., 18, 16729–16745,Short summary
We present an intercomparison of the airborne water vapor measurements during the ML-CIRRUS mission. Although the agreement of the hygrometers significantly improved compared to studies from recent decades, systematic differences remain under specific meteorological conditions. We compare the measurements to model data, where we observe a model wet bias in the lower stratosphere close to the tropopause, likely caused by a blurred humidity gradient in the model tropopause.
Elizabeth C. Weatherhead, Jerald Harder, Eduardo A. Araujo-Pradere, Greg Bodeker, Jason M. English, Lawrence E. Flynn, Stacey M. Frith, Jeffrey K. Lazo, Peter Pilewskie, Mark Weber, and Thomas N. Woods
Atmos. Chem. Phys., 17, 15069–15093,Short summary
Satellite overlap is often carried out as a check on the stability of the data collected. We looked at how length of overlap influences how much information can be derived from the overlap period. Several results surprised us: the confidence we could have in the matchup of two records was independent of the offset, and understanding of the relative drift between the two satellite data sets improved significantly with 2–3 years of overlap. Sudden jumps could easily be confused with drift.
Rintaro Okamura, Hironobu Iwabuchi, and K. Sebastian Schmidt
Atmos. Meas. Tech., 10, 4747–4759,Short summary
Three-dimensional (3-D) radiative transfer effects are a major source of retrieval errors in satellite-based optical remote sensing of clouds. Multi-pixel, multispectral approaches based on deep learning are proposed for retrieval of cloud optical thickness and droplet effective radius. A feasibility test shows that proposed retrieval methods are effective to obtain accurate cloud properties. Use of the convolutional neural network is effective to reduce 3-D radiative transfer effects.
Maria A. Navarro, Alfonso Saiz-Lopez, Carlos A. Cuevas, Rafael P. Fernandez, Elliot Atlas, Xavier Rodriguez-Lloveras, Douglas Kinnison, Jean-Francois Lamarque, Simone Tilmes, Troy Thornberry, Andrew Rollins, James W. Elkins, Eric J. Hintsa, and Fred L. Moore
Atmos. Chem. Phys., 17, 9917–9930,Short summary
Inorganic bromine (Bry) plays an important role in ozone layer depletion. Based on aircraft observations of organic bromine species and chemistry simulations, we model the Bry abundances over the Pacific tropical tropopause. Our results show BrO and Br as the dominant species during daytime hours, and BrCl and BrONO2 as the nighttime dominant species over the western and eastern Pacific, respectively. The difference in the partitioning is due to changes in the abundance of O3, NO2, and Cly.
Robert L. Herman, Eric A. Ray, Karen H. Rosenlof, Kristopher M. Bedka, Michael J. Schwartz, William G. Read, Robert F. Troy, Keith Chin, Lance E. Christensen, Dejian Fu, Robert A. Stachnik, T. Paul Bui, and Jonathan M. Dean-Day
Atmos. Chem. Phys., 17, 6113–6124,Short summary
This study reports new aircraft field observations of elevated water vapor greater than 10 ppmv in the overworld stratosphere over the summertime continental US. Back trajectories from the flight track intersect overshooting convective tops within the previous 1 to 7 days, suggesting that ice is convectively and irreversibly transported to the stratosphere in the most energetic overshooting convective events. Satellite measurements (Aura MLS) indicate that such events are uncommon (< 1 %).
Bodo Werner, Jochen Stutz, Max Spolaor, Lisa Scalone, Rasmus Raecke, James Festa, Santo Fedele Colosimo, Ross Cheung, Catalina Tsai, Ryan Hossaini, Martyn P. Chipperfield, Giorgio S. Taverna, Wuhu Feng, James W. Elkins, David W. Fahey, Ru-Shan Gao, Erik J. Hintsa, Troy D. Thornberry, Free Lee Moore, Maria A. Navarro, Elliot Atlas, Bruce C. Daube, Jasna Pittman, Steve Wofsy, and Klaus Pfeilsticker
Atmos. Chem. Phys., 17, 1161–1186,Short summary
The paper reports on inorganic and organic bromine measured in the tropical tropopause layer (TTL) over the eastern Pacific in early 2013. Bryinorg is found to increase from a mean of 2.63 ± 1.04 ppt for θ in the range of 350–360 K to 5.11 ± 1.57 ppt for θ=390 ± 400 K, whereas in the subtropical lower stratosphere, it reaches 7.66 ± 2.95 ppt for θ in the range of 390–400 K. Within the TTL, total bromine is found to range from 20.3 ppt to 22.3 ppt.
Shi Song, K. Sebastian Schmidt, Peter Pilewskie, Michael D. King, Andrew K. Heidinger, Andi Walther, Hironobu Iwabuchi, Gala Wind, and Odele M. Coddington
Atmos. Chem. Phys., 16, 13791–13806,Short summary
The radiative effects of spatially complex cloud fields are notoriously difficult to estimate and are afflicted with errors up to ±50 % of the incident solar radiation. We find that horizontal photon transport, the leading cause for these three-dimensional effects, manifests itself through a spectral fingerprint – a new observable that holds promise for reducing the errors associated with spatial complexity by moving the problem to the spectral dimension.
Andrew W. Rollins, Troy D. Thornberry, Steven J. Ciciora, Richard J. McLaughlin, Laurel A. Watts, Thomas F. Hanisco, Esther Baumann, Fabrizio R. Giorgetta, Thaopaul V. Bui, David W. Fahey, and Ru-Shan Gao
Atmos. Meas. Tech., 9, 4601–4613,Short summary
In situ measurements of SO2 in the tropical UT–LS have been scarce, in part due to limitations of existing instrumentation. Here we present a new laser-induced fluorescence instrument capable of measuring SO2 in the UT–LS region at single part-per-trillion (ppt) mixing ratios and demonstrate it on the NASA WB-57F aircraft up to 19.7 km altitude.
Stefan Kaufmann, Christiane Voigt, Tina Jurkat, Troy Thornberry, David W. Fahey, Ru-Shan Gao, Romy Schlage, Dominik Schäuble, and Martin Zöger
Atmos. Meas. Tech., 9, 939–953,Short summary
We present the development of a new airborne mass spectrometer AIMS-H2O for the fast and accurate measurement of water vapor in the upper troposphere and lower stratosphere. The high accuracy needed for e.g. quantification of atmospheric water vapor transport processes or cloud formation is achieved by an in-flight calibration of the instrument. AIMS-H2O is deployed on the DLR research aircraft HALO and Falcon where it covers a range of water vapor mixing ratios from 1 to 500 ppmv.
J. Meyer, C. Rolf, C. Schiller, S. Rohs, N. Spelten, A. Afchine, M. Zöger, N. Sitnikov, T. D. Thornberry, A. W. Rollins, Z. Bozóki, D. Tátrai, V. Ebert, B. Kühnreich, P. Mackrodt, O. Möhler, H. Saathoff, K. H. Rosenlof, and M. Krämer
Atmos. Chem. Phys., 15, 8521–8538,
T. D. Thornberry, A. W. Rollins, R. S. Gao, L. A. Watts, S. J. Ciciora, R. J. McLaughlin, and D. W. Fahey
Atmos. Meas. Tech., 8, 211–224,Short summary
The two-channel NOAA Water instrument was developed for in situ measurement of water vapor and cirrus cloud ice water content (IWC) in the upper troposphere and lower stratosphere. Tunable diode laser absorption is used to achieve accurate measurements at part per million H2O and low µg/m3 IWC. This paper reports the instrument’s design and performance achieved during its first aircraft deployment on the NASA Global Hawk during the 2013 ATTREX mission in the tropical tropopause layer.
A. C. Kren, D. R. Marsh, A. K. Smith, and P. Pilewskie
Atmos. Chem. Phys., 14, 4843–4856,
S. E. Pusede, D. R. Gentner, P. J. Wooldridge, E. C. Browne, A. W. Rollins, K.-E. Min, A. R. Russell, J. Thomas, L. Zhang, W. H. Brune, S. B. Henry, J. P. DiGangi, F. N. Keutsch, S. A. Harrold, J. A. Thornton, M. R. Beaver, J. M. St. Clair, P. O. Wennberg, J. Sanders, X. Ren, T. C. VandenBoer, M. Z. Markovic, A. Guha, R. Weber, A. H. Goldstein, and R. C. Cohen
Atmos. Chem. Phys., 14, 3373–3395,
T. D. Thornberry, A. W. Rollins, R. S. Gao, L. A. Watts, S. J. Ciciora, R. J. McLaughlin, C. Voigt, B. Hall, and D. W. Fahey
Atmos. Meas. Tech., 6, 1461–1475,
I. Ermolli, K. Matthes, T. Dudok de Wit, N. A. Krivova, K. Tourpali, M. Weber, Y. C. Unruh, L. Gray, U. Langematz, P. Pilewskie, E. Rozanov, W. Schmutz, A. Shapiro, S. K. Solanki, and T. N. Woods
Atmos. Chem. Phys., 13, 3945–3977,
Y. L. Roberts, P. Pilewskie, B. C. Kindel, D. R. Feldman, and W. D. Collins
Atmos. Chem. Phys., 13, 3133–3147,
Related subject area
Subject: Gases | Technique: Remote Sensing | Topic: Instruments and PlatformsPolarization performance simulation for the GeoXO atmospheric composition instrument: NO2 retrieval impactsThe impact of aerosol fluorescence on long-term water vapor monitoring by Raman lidar and evaluation of a potential correction methodIntegrated airborne investigation of the air composition over the Russian sector of the ArcticMeasurement of the vertical atmospheric density profile from the X-ray Earth occultation of the Crab Nebula with Insight-HXMTQuantification and mitigation of the instrument effects and uncertainties of the airborne limb imaging FTIR GLORIAImproved calibration procedures for the EM27/SUN spectrometers of the COllaborative Carbon Column Observing Network (COCCON)Ground-based Ku-band microwave observations of ozone in the polar middle atmosphereEvaluation of the High Altitude Lidar Observatory Methane Retrievals During the Summer 2019 ACT-America CampaignTraceable total ozone column retrievals from direct solar spectral irradiance measurements in the ultravioletFar-ultraviolet airglow remote sensing measurements on Feng Yun 3-D meteorological satelliteThe NO2 camera based on gas correlation spectroscopyTotal water vapour columns derived from Sentinel 5P using the AMC-DOAS methodMobile and high-spectral-resolution Fabry–Pérot interferometer spectrographs for atmospheric remote sensingDiurnal variability of stratospheric column NO2 measured using direct solar and lunar spectra over Table Mountain, California (34.38° N)The “ideal” spectrograph for atmospheric observationsDifferential absorption lidar for water vapor isotopologues in the 1.98 µm spectral region: sensitivity analysis with respect to regional atmospheric variabilityAtmospheric carbon dioxide measurement from aircraft and comparison with OCO-2 and CarbonTracker model dataLong-term column-averaged greenhouse gas observations using a COCCON spectrometer at the high-surface-albedo site in Gobabeb, NamibiaA fully automated Dobson sun spectrophotometer for total column ozone and Umkehr measurementsSlit homogenizer introduced performance gain analysis based on the Sentinel-5/UVNS spectrometerOn the capability of the future ALTIUS ultraviolet–visible–near-infrared limb sounder to constrain modelled stratospheric ozoneMicroPulse DIAL (MPD) – a diode-laser-based lidar architecture for quantitative atmospheric profilingA multi-purpose, multi-rotor drone system for long-range and high-altitude volcanic gas plume measurementsTropospheric NO2 measurements using a three-wavelength optical parametric oscillator differential absorption lidarSpectral calibration of the MethaneAIR instrumentThe design and development of a tuneable and portable radiation source for in situ spectrometer characterisationPerformance of an open-path near-infrared measurement system for measurements of CO2 and CH4 during extended field trialsDetermination of the emission rates of CO2 point sources with airborne lidarThe GHGSat-D imaging spectrometerThermal and near-infrared sensor for carbon observation Fourier transform spectrometer-2 (TANSO-FTS-2) on the Greenhouse gases Observing SATellite-2 (GOSAT-2) during its first year in orbitPrediction model for diffuser-induced spectral features in imaging spectrometersCharacterization and potential for reducing optical resonances in Fourier transform infrared spectrometers of the Network for the Detection of Atmospheric Composition Change (NDACC)MUCCnet: Munich Urban Carbon Column networkEmission Monitoring Mobile Experiment (EMME): an overview and first results of the St. Petersburg megacity campaign 2019Effect of polyoxymethylene (POM-H Delrin) off-gassing within the Pandora head sensor on direct-sun and multi-axis formaldehyde column measurements in 2016–2019A powerful lidar system capable of 1 h measurements of water vapour in the troposphere and the lower stratosphere as well as the temperature in the upper stratosphere and mesosphereFirst high-resolution tropospheric NO2 observations from the Ultraviolet Visible Hyperspectral Imaging Spectrometer (UVHIS)Quantitative imaging of volcanic SO2 plumes using Fabry–Pérot interferometer correlation spectroscopyThree decades of tropospheric ozone lidar development at Garmisch-Partenkirchen, GermanySolar tracker with optical feedback and continuous rotationAssessment of global total column water vapor sounding using a spaceborne differential absorption radarIntercomparison of low- and high-resolution infrared spectrometers for ground-based solar remote sensing measurements of total column concentrations of CO2, CH4, and CORecommendations for spectral fitting of SO2 from miniature multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurementsAtmospheric ammonia (NH3) over the Paris megacity: 9 years of total column observations from ground-based infrared remote sensingIn-flight calibration results of the TROPOMI payload on board the Sentinel-5 Precursor satelliteThe use of the 1.27 µm O2 absorption band for greenhouse gas monitoring from space and application to MicroCarbTowards spaceborne monitoring of localized CO2 emissions: an instrument concept and first performance assessmentEvaluating different methods for elevation calibration of MAX-DOAS (Multi AXis Differential Optical Absorption Spectroscopy) instruments during the CINDI-2 campaignSpectral sizing of a coarse-spectral-resolution satellite sensor for XCO2Benefit of ozone observations from Sentinel-5P and future Sentinel-4 missions on tropospheric composition
Aaron Pearlman, Monica Cook, Boryana Efremova, Francis Padula, Lok Lamsal, Joel McCorkel, and Joanna Joiner
Atmos. Meas. Tech., 15, 4489–4501,Short summary
NOAA’s Geostationary Extended Observations (GeoXO) constellation is planned to consist of an atmospheric composition instrument (ACX) to support air quality forecasting and monitoring. As design trade-offs are being studied, we investigated one parameter, the polarization sensitivity, which has yet to be fully documented for NO2 retrievals. Our simulation study explores these impacts to inform the ACX’s development and better understand polarization’s role in trace gas retrievals.
Fernando Chouza, Thierry Leblanc, Mark Brewer, Patrick Wang, Giovanni Martucci, Alexander Haefele, Hélène Vérèmes, Valentin Duflot, Guillaume Payen, and Philippe Keckhut
Atmos. Meas. Tech., 15, 4241–4256,Short summary
The comparison of water vapor lidar measurements with co-located radiosondes and aerosol backscatter profiles indicates that laser-induced aerosol fluorescence in smoke layers injected into the stratosphere can introduce very large and chronic wet biases above 15 km, thus impacting the ability of these systems to accurately estimate long-term water vapor trends. The proposed correction method presented in this work is able to reduce this fluorescence-induced bias from 75 % to under 5 %.
Boris D. Belan, Gerard Ancellet, Irina S. Andreeva, Pavel N. Antokhin, Viktoria G. Arshinova, Mikhail Y. Arshinov, Yurii S. Balin, Vladimir E. Barsuk, Sergei B. Belan, Dmitry G. Chernov, Denis K. Davydov, Alexander V. Fofonov, Georgii A. Ivlev, Sergei N. Kotel'nikov, Alexander S. Kozlov, Artem V. Kozlov, Katharine Law, Andrey V. Mikhal'chishin, Igor A. Moseikin, Sergei V. Nasonov, Philippe Nédélec, Olesya V. Okhlopkova, Sergei E. Ol'kin, Mikhail V. Panchenko, Jean-Daniel Paris, Iogannes E. Penner, Igor V. Ptashnik, Tatyana M. Rasskazchikova, Irina K. Reznikova, Oleg A. Romanovskii, Alexander S. Safatov, Denis E. Savkin, Denis V. Simonenkov, Tatyana K. Sklyadneva, Gennadii N. Tolmachev, Semyon V. Yakovlev, and Polina N. Zenkova
Atmos. Meas. Tech., 15, 3941–3967,Short summary
The change of the global climate is most pronounced in the Arctic, where the air temperature increases faster than the global average. This is associated with an increase in the concentration of greenhouse gases in the atmosphere. It is important to study how the air composition in the Arctic changes in the changing climate. Thus this integrated experiment was carried out to measure the composition of the troposphere in the Russian sector of the Arctic from on board the aircraft laboratory.
Daochun Yu, Haitao Li, Baoquan Li, Mingyu Ge, Youli Tuo, Xiaobo Li, Wangchen Xue, Yaning Liu, Aoying Wang, Yajun Zhu, and Bingxian Luo
Atmos. Meas. Tech., 15, 3141–3159,Short summary
In this work, the measurement of vertical atmospheric density profiles using X-ray Earth occultation is investigated. The Earth’s density profile for the lower thermosphere is obtained with Insight-HXMT. It is shown that the Insight-HXMT X-ray satellite of China can be used as an X-ray atmospheric diagnostics instrument for the upper atmosphere. The Insight-HXMT satellite can, with other X-ray astronomical satellites in orbit, form a network for X-ray Earth occultation sounding in the future.
Jörn Ungermann, Anne Kleinert, Guido Maucher, Irene Bartolomé, Felix Friedl-Vallon, Sören Johansson, Lukas Krasauskas, and Tom Neubert
Atmos. Meas. Tech., 15, 2503–2530,Short summary
GLORIA is a 2-D infrared imaging spectrometer operated on two high-flying research aircraft. This paper details our instrument calibration and characterization efforts, which in particular leverage in-flight data almost exclusively and often exploit the novel 2-D nature of the measurements. We show that the instrument surpasses the original instrument specifications and conclude by analyzing how the derived errors affect temperature and ozone retrievals, two of our main derived quantities.
Carlos Alberti, Frank Hase, Matthias Frey, Darko Dubravica, Thomas Blumenstock, Angelika Dehn, Paolo Castracane, Gregor Surawicz, Roland Harig, Bianca C. Baier, Caroline Bès, Jianrong Bi, Hartmut Boesch, André Butz, Zhaonan Cai, Jia Chen, Sean M. Crowell, Nicholas M. Deutscher, Dragos Ene, Jonathan E. Franklin, Omaira García, David Griffith, Bruno Grouiez, Michel Grutter, Abdelhamid Hamdouni, Sander Houweling, Neil Humpage, Nicole Jacobs, Sujong Jeong, Lilian Joly, Nicholas B. Jones, Denis Jouglet, Rigel Kivi, Ralph Kleinschek, Morgan Lopez, Diogo J. Medeiros, Isamu Morino, Nasrin Mostafavipak, Astrid Müller, Hirofumi Ohyama, Paul I. Palmer, Mahesh Pathakoti, David F. Pollard, Uwe Raffalski, Michel Ramonet, Robbie Ramsay, Mahesh Kumar Sha, Kei Shiomi, William Simpson, Wolfgang Stremme, Youwen Sun, Hiroshi Tanimoto, Yao Té, Gizaw Mengistu Tsidu, Voltaire A. Velazco, Felix Vogel, Masataka Watanabe, Chong Wei, Debra Wunch, Marcia Yamasoe, Lu Zhang, and Johannes Orphal
Atmos. Meas. Tech., 15, 2433–2463,Short summary
Space-borne greenhouse gas missions require ground-based validation networks capable of providing fiducial reference measurements. Here, considerable refinements of the calibration procedures for the COllaborative Carbon Column Observing Network (COCCON) are presented. Laboratory and solar side-by-side procedures for the characterization of the spectrometers have been refined and extended. Revised calibration factors for XCO2, XCO and XCH4 are provided, incorporating 47 new spectrometers.
David A. Newnham, Mark A. Clilverd, William D. J. Clark, Michael Kosch, Pekka T. Verronen, and Alan E. E. Rogers
Atmos. Meas. Tech., 15, 2361–2376,Short summary
Ozone (O3) is an important trace gas in the mesosphere and lower thermosphere (MLT), affecting heating rates and chemistry. O3 profiles measured by the Ny-Ålesund Ozone in the Mesosphere Instrument agree with Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) for winter night-time, but autumn twilight SABER abundances are up to 50 % higher. O3 abundances in the MLT from two different SABER channels also show significant differences for both autumn twilight and summer daytime.
Rory A. Barton-Grimley, Amin R. Nehrir, Susan A. Kooi, James E. Collins, David B. Harper, Anthony Notari, Joseph Lee, Joshua P. DiGangi, Yonghoon Choi, and Kenneth J. Davis
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
HALO is a multi-function lidar that measures CH4 columns and profiles of H2O mixing ratio and aerosol/cloud optical properties. HALO supports carbon cycle, weather/dynamics, and radiation sciences suborbital research and is a technology testbed for future space-based differential absorption lidar missions. In 2019 HALO collected CH4 columns and aerosol/cloud profiles during the ACT-America campaign. Here we assess HALO's CH4 accuracy and precision compared to co-located in-situ observations.
Luca Egli, Julian Gröbner, Gregor Hülsen, Herbert Schill, and René Stübi
Atmos. Meas. Tech., 15, 1917–1930,Short summary
This study presents traceable total column ozone retrievals from direct solar spectral irradiance measurements. The retrieved ozone does not require any field calibration with a reference instrument as it is required for other operational network instruments such as Brewer or Dobson. Total column ozone can be retrieved with a traceable overall standard uncertainty of less than 0.8 % indicating a benchmark uncertainty for total column ozone measurements.
Yungang Wang, Liping Fu, Fang Jiang, Xiuqing Hu, Chengbao Liu, Xiaoxin Zhang, Jiawei Li, Zhipeng Ren, Fei He, Lingfeng Sun, Ling Sun, Zhongdong Yang, Peng Zhang, Jingsong Wang, and Tian Mao
Atmos. Meas. Tech., 15, 1577–1586,Short summary
Far-ultraviolet (FUV) airglow radiation is particularly well suited for space-based remote sensing. The Ionospheric Photometer (IPM) instrument carried aboard the Feng Yun 3-D satellite measures the spectral radiance of the Earth FUV airglow. IPM is a tiny, highly sensitive, and robust remote sensing instrument. Initial results demonstrate that the performance of IPM meets the designed requirement and therefore can be used to study the thermosphere and ionosphere in the future.
Leon Kuhn, Jonas Kuhn, Thomas Wagner, and Ulrich Platt
Atmos. Meas. Tech., 15, 1395–1414,Short summary
We present a novel instrument for imaging measurements of NO2 with high spatiotemporal resolution based on gas correlation spectroscopy, called the GCS NO2 camera. The instrument works by placing two gas cells (cuvettes) in front of two photosensor arrays, one filled with air and one filled with a high concentration of NO2, acting as a non-dispersive spectral filter. NO2 images are then generated on the basis of the signal ratio of the two channels in the spectral region of 430–445 nm.
Tobias Küchler, Stefan Noël, Heinrich Bovensmann, John Philip Burrows, Thomas Wagner, Christian Borger, Tobias Borsdorff, and Andreas Schneider
Atmos. Meas. Tech., 15, 297–320,Short summary
We applied the air-mass-corrected differential optical absorption spectroscopy (AMC-DOAS) method to derive total column water vapour (TCWV) from Sentinel-5P measurements and compared it to independent data sets. The correlation coefficients of typically more than 0.9 and the small deviations up to 2.5 kg m−2 reveal good agreement between our data product and other TCWV data sets. In particular for the different Sentinel-5P water vapour products, the deviations are around 1 kg m−2.
Jonas Kuhn, Nicole Bobrowski, Thomas Wagner, and Ulrich Platt
Atmos. Meas. Tech., 14, 7873–7892,Short summary
We propose spectrograph implementations using Fabry–Pérot interferometers for atmospheric trace gas remote sensing. Compared with widely used grating spectrographs, we find substantial light throughput and mobility advantages for high resolving powers. Besides lowering detection limits and increasing the spatial and temporal resolution of many atmospheric trace gas measurements, this approach might enable remote sensing of further important gases such as tropospheric OH radicals.
King-Fai Li, Ryan Khoury, Thomas J. Pongetti, Stanley P. Sander, Franklin P. Mills, and Yuk L. Yung
Atmos. Meas. Tech., 14, 7495–7510,Short summary
Nitrogen dioxide (NO2) plays a dominant role in the stratospheric ozone-destroying catalytic cycle. We have retrieved the diurnal cycle of NO2 over Table Mountain in Southern California, USA, during a week in October 2018. Under clean conditions, we are able to predict the diurnal cycle using standard photochemistry. On a day with significant pollution, we see the effect of NO2 sources in the nearby Los Angeles Basin.
Ulrich Platt, Thomas Wagner, Jonas Kuhn, and Thomas Leisner
Atmos. Meas. Tech., 14, 6867–6883,Short summary
Absorption spectroscopy of scattered sunlight is extremely useful for the analysis of atmospheric trace gas distributions. A central parameter for the achievable sensitivity of spectroscopic instruments is the light throughput, which can be enhanced in a number of ways. We present new ideas and considerations of how instruments could be optimized. Particular emphasis is on arrays of massively parallel instruments. Such arrays can reduce the size and weight of instruments by orders of magnitude.
Jonas Hamperl, Clément Capitaine, Jean-Baptiste Dherbecourt, Myriam Raybaut, Patrick Chazette, Julien Totems, Bruno Grouiez, Laurence Régalia, Rosa Santagata, Corinne Evesque, Jean-Michel Melkonian, Antoine Godard, Andrew Seidl, Harald Sodemann, and Cyrille Flamant
Atmos. Meas. Tech., 14, 6675–6693,Short summary
Laser active remote sensing of tropospheric water vapor is a promising technology for enhancing our understanding of processes governing the global hydrological cycle. We investigate the potential of a ground-based lidar to monitor the main water vapor isotopes at high spatio-temporal resolutions in the lower troposphere. Using a realistic end-to-end simulator, we show that high-precision measurements can be achieved within a range of 1.5 km, in mid-latitude or tropical environments.
Qin Wang, Farhan Mustafa, Lingbing Bu, Shouzheng Zhu, Jiqiao Liu, and Weibiao Chen
Atmos. Meas. Tech., 14, 6601–6617,Short summary
In this work, an airborne experiment was carried out to validate a newly developed CO2 monitoring IPDA lidar against the in situ measurements obtained from a commercial CO2 monitoring instrument installed on an aircraft. The XCO2 values calculated with the IPDA lidar measurements were compared with the dry-air CO2 mole fraction measurements obtained from the in situ instruments, and the results showed a good agreement between the two datasets.
Matthias M. Frey, Frank Hase, Thomas Blumenstock, Darko Dubravica, Jochen Groß, Frank Göttsche, Martin Handjaba, Petrus Amadhila, Roland Mushi, Isamu Morino, Kei Shiomi, Mahesh Kumar Sha, Martine de Mazière, and David F. Pollard
Atmos. Meas. Tech., 14, 5887–5911,Short summary
In this study, we present measurements of carbon dioxide, methane and carbon monoxide from a recently established site in Gobabeb, Namibia. Gobabeb is the first site observing these gases on the African mainland and improves the global coverage of measurement sites. Gobabeb is a hyperarid desert site, offering unique characteristics. Measurements started 2015 as part of the COllaborative Carbon Column Observing Network. We compare our results with other datasets and find a good agreement.
René Stübi, Herbert Schill, Jörg Klausen, Eliane Maillard Barras, and Alexander Haefele
Atmos. Meas. Tech., 14, 5757–5769,Short summary
In the first half of the 20th century, Prof. Dobson developed an instrument to measure the ozone column. Around 50 of these Dobson instruments, manufactured in the second half of the 20th century, are still used today to monitor the state of the ozone layer. Started in 1926, the Arosa series was, until recently, based on manually operated Dobsons. To ensure its future operation, a fully automated version of the Dobson has been developed. This well-working automated system is described here.
Timon Hummel, Christian Meister, Corneli Keim, Jasper Krauser, and Mark Wenig
Atmos. Meas. Tech., 14, 5459–5472,Short summary
The impact of heterogeneous scene radiance affects the quality of trace gas retrieval products of Earth observation imaging spectrometers. This effect can be mitigated by introducing on-board hardware solutions called slit homogenizers, which scramble the light entering the instrument and thereby make it insensitive to Earth scene contrast. Here we present a comprehensive modeling of the slit homogenizer present in the Sentinel-5/UVNS instrument and quantify the spectral performance.
Quentin Errera, Emmanuel Dekemper, Noel Baker, Jonas Debosscher, Philippe Demoulin, Nina Mateshvili, Didier Pieroux, Filip Vanhellemont, and Didier Fussen
Atmos. Meas. Tech., 14, 4737–4753,Short summary
ALTIUS is a micro-satellite which will measure the distribution of the ozone layer. Micro-satellites are intended to be cost-effective, but does this make the ALTIUS measurements any less valuable? To answer this, we simulated ALTIUS data and measured how it could constrain a model of the ozone layer; we then compared these results with those obtained from the state-of-the-art NASA Aura MLS satellite ozone measurements. The outcome shows us that the ALTIUS
budgetinstrument is indeed valuable.
Scott M. Spuler, Matthew Hayman, Robert A. Stillwell, Joshua Carnes, Todd Bernatsky, and Kevin S. Repasky
Atmos. Meas. Tech., 14, 4593–4616,Short summary
Continuous water vapor and temperature profiles are critically needed for improved understanding of the lower atmosphere and potential advances in weather forecasting skill. To address this observation need, an active remote sensing technology based on a diode-laser-based lidar architecture is being developed. We discuss the details of the lidar architecture and analyze how it addresses a national-scale profiling network's need to provide continuous thermodynamic observations.
Bo Galle, Santiago Arellano, Nicole Bobrowski, Vladimir Conde, Tobias P. Fischer, Gustav Gerdes, Alexandra Gutmann, Thorsten Hoffmann, Ima Itikarai, Tomas Krejci, Emma J. Liu, Kila Mulina, Scott Nowicki, Tom Richardson, Julian Rüdiger, Kieran Wood, and Jiazhi Xu
Atmos. Meas. Tech., 14, 4255–4277,Short summary
Measurements of volcanic gases are important for geophysical research, risk assessment and environmental impact studies. Some gases, like SO2 and BrO, may be studied from the ground at a safe distance using remote sensing techniques. Many other gases require in situ access to the gas plume. Here, a drone may be an attractive alternative. This paper describes a drone specially adapted for volcanic gas studies and demonstrates its use in a field campaign at Manam volcano in Papua New Guinea.
Jia Su, M. Patrick McCormick, Matthew S. Johnson, John T. Sullivan, Michael J. Newchurch, Timothy A. Berkoff, Shi Kuang, and Guillaume P. Gronoff
Atmos. Meas. Tech., 14, 4069–4082,Short summary
A new technique using a three-wavelength differential absorption lidar (DIAL) technique based on an optical parametric oscillator (OPO) laser is proposed to obtain more accurate measurements of NO2. The retrieval uncertainties in aerosol extinction using the three-wavelength DIAL technique are reduced to less than 2 % of those when using the two-wavelength DIAL technique. Hampton University (HU) lidar NO2 profiles are compared with simulated data from the WRF-Chem model, and they agree well.
Carly Staebell, Kang Sun, Jenna Samra, Jonathan Franklin, Christopher Chan Miller, Xiong Liu, Eamon Conway, Kelly Chance, Scott Milligan, and Steven Wofsy
Atmos. Meas. Tech., 14, 3737–3753,Short summary
Given the high global warming potential of CH4, the identification and subsequent reduction of anthropogenic CH4 emissions presents a significant opportunity for climate change mitigation. Satellites are an integral piece of this puzzle, providing data to quantify emissions at a variety of spatial scales. This work presents the spectral calibration of MethaneAIR, the airborne instrument used as a test bed for the forthcoming MethaneSAT satellite.
Marek Šmíd, Geiland Porrovecchio, Jiří Tesař, Tim Burnitt, Luca Egli, Julian Grőbner, Petr Linduška, and Martin Staněk
Atmos. Meas. Tech., 14, 3573–3582,Short summary
We designed and developed a tuneable and portable radiation source (TuPS) to provide a reference wavelength scale, with a bandwidth of emitted radiation of 0.13 nm and uncertainty in wavelength of 0.02 nm. TuPS was successfully used for the in-field characterization of 14 Dobson spectrophotometers in campaigns in Europe. The line spread functions of Dobsons measured by TuPS in conjunction with the cross-sections from IUP improves the consistency between the Dobson and Brewer from 3 % to 1 %.
Nicholas M. Deutscher, Travis A. Naylor, Christopher G. R. Caldow, Hamish L. McDougall, Alex G. Carter, and David W. T. Griffith
Atmos. Meas. Tech., 14, 3119–3130,Short summary
This work describes the performance of an open-path measurement system for greenhouse gases in an extended field trial. The instrument obtained measurement repeatability of 0.1 % or better for CO2 and CH4 measurements over a 1.55 km one-way pathway. Comparison to co-located in situ measurements allows characterisation of biases relative to global reference scales. The research was done to show the applicability of the technique and its ability to detect atmospheric-relevant sources and sinks.
Sebastian Wolff, Gerhard Ehret, Christoph Kiemle, Axel Amediek, Mathieu Quatrevalet, Martin Wirth, and Andreas Fix
Atmos. Meas. Tech., 14, 2717–2736,Short summary
We report on CO2 emissions of a coal-fired power plant derived from flight measurements performed with the IPDA lidar CHARM-F during the CoMet campaign in spring 2018. Despite the results being in broad agreement with reported emissions, we observe strong variations between successive flyovers. Using a high-resolution large eddy simulation, we identify strong atmospheric turbulence as the cause for the variations and recommend more favorable measurement conditions for future campaign planning.
Dylan Jervis, Jason McKeever, Berke O. A. Durak, James J. Sloan, David Gains, Daniel J. Varon, Antoine Ramier, Mathias Strupler, and Ewan Tarrant
Atmos. Meas. Tech., 14, 2127–2140,Short summary
We describe how the GHGSat-D demonstration satellite is designed and operated in order to measure greenhouse gas emissions from different types of industrial facilities. The distinguishing features of GHGSat-D, or
Claire, are its compact size (< 15 kg) and high spatial resolution (< 50 m). We give a mathematical model of the instrument and describe the techniques used to infer a methane concentration from a measurement of the sunlight that has reflected off the Earth's surface.
Hiroshi Suto, Fumie Kataoka, Nobuhiro Kikuchi, Robert O. Knuteson, Andre Butz, Markus Haun, Henry Buijs, Kei Shiomi, Hiroko Imai, and Akihiko Kuze
Atmos. Meas. Tech., 14, 2013–2039,Short summary
The Japanese Greenhouse gases Observing SATellite-2 (GOSAT-2), in orbit since October 2018, is the follow-up mission of GOSAT, which has been operating since January 2009. Both satellites are dedicated to the monitoring of global carbon dioxide and methane to further knowledge of the global carbon cycle. This paper has reported on the function and performance of the TANSO-FTS-2 instrument, level-1 data processing, and calibrations for the first year of GOSAT-2 observation.
Florian Richter, Corneli Keim, Jérôme Caron, Jasper Krauser, Dennis Weise, and Mark Wenig
Atmos. Meas. Tech., 14, 1561–1571,Short summary
Much effort has gone into obtaining crucial information about the progress of climate change, which depends on trace gases in the Earth's atmosphere. Satellite-based imaging spectrometers are used to record the Earth's reflectance in order to quantify the concentration of relevant trace gases. This work contributes an approach to a well-known calibration uncertainty regarding diffuser speckle and could significantly reduce overheads in the future planning phases of such instruments.
Thomas Blumenstock, Frank Hase, Axel Keens, Denis Czurlok, Orfeo Colebatch, Omaira Garcia, David W. T. Griffith, Michel Grutter, James W. Hannigan, Pauli Heikkinen, Pascal Jeseck, Nicholas Jones, Rigel Kivi, Erik Lutsch, Maria Makarova, Hamud K. Imhasin, Johan Mellqvist, Isamu Morino, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Uwe Raffalski, Markus Rettinger, John Robinson, Matthias Schneider, Christian Servais, Dan Smale, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, and Voltaire A. Velazco
Atmos. Meas. Tech., 14, 1239–1252,Short summary
This study investigates the level of channeling (optical resonances) of each FTIR spectrometer within the Network for the Detection of Atmospheric Composition Change (NDACC). Since the air gap of the beam splitter is a significant source of channeling, we propose new beam splitters with an increased wedge of the air gap. This study shows the potential for reducing channeling in the FTIR spectrometers operated by the NDACC, thereby increasing the quality of recorded spectra across the network.
Florian Dietrich, Jia Chen, Benno Voggenreiter, Patrick Aigner, Nico Nachtigall, and Björn Reger
Atmos. Meas. Tech., 14, 1111–1126,Short summary
Climate change is one of the defining issues of our time. However, most of the current emission estimates are based on calculations, not on actual measurements as it is difficult to quantify the emissions of large sources such as cities. This study shows how to use the relatively new approach of column measurements to quantify urban greenhouse gas emissions in an exact way using only a few compact measurement systems. The approach can be used to evaluate the effectiveness of mitigation policies.
Maria V. Makarova, Carlos Alberti, Dmitry V. Ionov, Frank Hase, Stefani C. Foka, Thomas Blumenstock, Thorsten Warneke, Yana A. Virolainen, Vladimir S. Kostsov, Matthias Frey, Anatoly V. Poberovskii, Yuri M. Timofeyev, Nina N. Paramonova, Kristina A. Volkova, Nikita A. Zaitsev, Egor Y. Biryukov, Sergey I. Osipov, Boris K. Makarov, Alexander V. Polyakov, Viktor M. Ivakhov, Hamud Kh. Imhasin, and Eugene F. Mikhailov
Atmos. Meas. Tech., 14, 1047–1073,Short summary
Fundamental understanding of the major processes driving climate change is a key problem which is to be solved, not only on a global but also on a regional scale. The Emission Monitoring Mobile Experiment (EMME) carried out in 2019 with two portable Bruker EM27/SUN spectrometers as core instruments provided new information on the emissions of greenhouse (CO2, CH4) and reactive (CO, NOx) gases from St. Petersburg (Russia), which is the largest northern megacity with a population of 5 million.
Elena Spinei, Martin Tiefengraber, Moritz Müller, Manuel Gebetsberger, Alexander Cede, Luke Valin, James Szykman, Andrew Whitehill, Alexander Kotsakis, Fernando Santos, Nader Abbuhasan, Xiaoyi Zhao, Vitali Fioletov, Sum Chi Lee, and Robert Swap
Atmos. Meas. Tech., 14, 647–663,Short summary
Plastics are widely used in everyday life and scientific equipment. This paper presents Delrin plastic off-gassing as a function of temperature on the atmospheric measurements of formaldehyde by Pandora spectroscopic instruments. The sealed telescope assembly containing Delrin components emitted large amounts of formaldehyde at 30–45 °C, interfering with the Pandora measurements. These results have a broader implication since electronic products often experience the same temperature.
Lisa Klanner, Katharina Höveler, Dina Khordakova, Matthias Perfahl, Christian Rolf, Thomas Trickl, and Hannes Vogelmann
Atmos. Meas. Tech., 14, 531–555,Short summary
The importance of water vapour as the most influential greenhouse gas and for air composition calls for detailed investigations. The details of the highly inhomogeneous distribution of water vapour can be determined with lidar, the very low concentrations at high altitudes imposing a major challenge. An existing water-vapour lidar in the Bavarian Alps was recently complemented by a powerful Raman lidar that provides water vapour up to 20 km and temperature up to 90 km within just 1 h.
Liang Xi, Fuqi Si, Yu Jiang, Haijin Zhou, Kai Zhan, Zhen Chang, Xiaohan Qiu, and Dongshang Yang
Atmos. Meas. Tech., 14, 435–454,Short summary
In this paper, we present a novel airborne imaging differential optical absorption spectroscopy (DOAS) instrument: the Ultraviolet Visible Hyperspectral Imaging Spectrometer (UVHIS), which is developed for trace gas monitoring and pollution mapping. In the first demonstration flight on 23 June 2018, the UVHIS instrument clearly detected several NO2 emission plumes transporting from south to north. UVHIS NO2 vertical columns are well correlated with ground-based mobile DOAS observations.
Christopher Fuchs, Jonas Kuhn, Nicole Bobrowski, and Ulrich Platt
Atmos. Meas. Tech., 14, 295–307,Short summary
We present first measurements of volcanic SO2 emissions with a novel imaging technique for atmospheric trace gases in the UV and visible spectral range. Periodic spectral Fabry–Pérot interferometer transmission features are matched to differential absorption cross sections of the investigated trace gas, yielding high selectivity and sensitivity. The technique can be extended to measure many other trace gases with high spatio-temporal resolution.
Thomas Trickl, Helmuth Giehl, Frank Neidl, Matthias Perfahl, and Hannes Vogelmann
Atmos. Meas. Tech., 13, 6357–6390,Short summary
Lidar sounding of ozone and other atmospheric constituents has proved to be an invaluable tool for atmospheric studies. The ozone lidar systems developed at Garmisch-Partenkirchen have reached an accuracy level almost matching that of in situ sensors. Since the late 1990s numerous important scientific discoveries have been made, such as the first observation of intercontinental transport of ozone and the very high occurrence of intrusions of stratospheric air into the troposphere.
John Robinson, Dan Smale, David Pollard, and Hisako Shiona
Atmos. Meas. Tech., 13, 5855–5871,Short summary
Solar trackers are used by spectrometers to measure atmospheric trace gas concentrations using direct-sun spectroscopy. The ideal tracker should be sufficiently accurate, highly reliable, and with a longevity that exceeds the lifetime of the spectrometer which it serves. It should also be affordable, easy to use, and not too complex should maintenance be required. We present a design that fulfils these requirements using some simple innovations.
Luis Millán, Richard Roy, and Matthew Lebsock
Atmos. Meas. Tech., 13, 5193–5205,Short summary
This paper describes the feasibility of using a differential absorption radar technique for the remote sensing of total column water vapor from a spaceborne platform.
Mahesh Kumar Sha, Martine De Mazière, Justus Notholt, Thomas Blumenstock, Huilin Chen, Angelika Dehn, David W. T. Griffith, Frank Hase, Pauli Heikkinen, Christian Hermans, Alex Hoffmann, Marko Huebner, Nicholas Jones, Rigel Kivi, Bavo Langerock, Christof Petri, Francis Scolas, Qiansi Tu, and Damien Weidmann
Atmos. Meas. Tech., 13, 4791–4839,Short summary
We present the results of the 2017 FRM4GHG campaign at the Sodankylä TCCON site aimed at characterising the assessment of several low-cost portable instruments for precise solar absorption measurements of column-averaged dry-air mole fractions of CO2, CH4, and CO. The test instruments provided stable and precise measurements of these gases with quantified small biases. This qualifies the instruments to complement TCCON and expand the global coverage of ground-based measurements of these gases.
Zoë Y. W. Davis and Robert McLaren
Atmos. Meas. Tech., 13, 3993–4008,Short summary
MAX-DOAS is a technique that can be used to measure pollutant concentrations and vertical profiles in the atmosphere via remote sensing of sky-scattered light with a telescope. Measuring SO2 is particularly challenging because of low light intensities in regions where SO2 absorbs solar radiation. Here, we performed experiments that document inaccuracies in these measurements as a function of spectral
fitting windows. We provide recommendations for measuring SO2 with greater accuracy.
Benoît Tournadre, Pascale Chelin, Mokhtar Ray, Juan Cuesta, Rebecca D. Kutzner, Xavier Landsheere, Audrey Fortems-Cheiney, Jean-Marie Flaud, Frank Hase, Thomas Blumenstock, Johannes Orphal, Camille Viatte, and Claude Camy-Peyret
Atmos. Meas. Tech., 13, 3923–3937,Short summary
We present some results about ammonia pollution because NH3, mainly emitted by agricultural activities, is a precursor of fine particles. This study is based on the first multiyear time series (2009–2017) of atmospheric NH3 ground-based measurements over the Paris megacity. This pollutant varies seasonally by 2 orders of magnitude, especially in spring. We highlight that this kind of instrument could be easily installed and is very useful for analyzing NH3 in other megacities or source regions.
Antje Ludewig, Quintus Kleipool, Rolf Bartstra, Robin Landzaat, Jonatan Leloux, Erwin Loots, Peter Meijering, Emiel van der Plas, Nico Rozemeijer, Frank Vonk, and Pepijn Veefkind
Atmos. Meas. Tech., 13, 3561–3580,Short summary
After the Sentinel-5 Precursor satellite launch on 13 October 2017, its single payload, the TROPOspheric Monitoring Instrument (TROPOMI), was tested and calibrated extensively. Changes due to ageing of the instrument and new insights have led to updates to the L1b processor and its calibration key data, leading to improvements of the data quality. Regularly scheduled calibration measurements are used in the nominal operations phase (since 30 April 2018) to correct instrument degradation.
Jean-Loup Bertaux, Alain Hauchecorne, Franck Lefèvre, François-Marie Bréon, Laurent Blanot, Denis Jouglet, Pierre Lafrique, and Pavel Akaev
Atmos. Meas. Tech., 13, 3329–3374,Short summary
Monitoring of greenhouse gases from space is usually done by measuring the quantity of CO2 and O2 in the atmosphere from their spectral absorption imprinted on the solar spectrum backscattered upwards. We show that the use of the near-infrared band of O2 at 1.27 µm, instead of the O2 band at 0.76 nm used up to now, may be more appropriate to better account for aerosols, in spite of a known airglow emission from ozone. The climate space mission MicroCarb (launched in 2021) includes this new band.
Johan Strandgren, David Krutz, Jonas Wilzewski, Carsten Paproth, Ilse Sebastian, Kevin R. Gurney, Jianming Liang, Anke Roiger, and André Butz
Atmos. Meas. Tech., 13, 2887–2904,Short summary
This paper presents the concept of a spaceborne imaging spectrometer targeting the routine monitoring of CO2 emissions from localized point sources down to an emission strength of about 1 Mt CO2 yr-1. Using high-resolution CO2 emission and albedo data, it is shown that CO2 plumes from point sources with an emission strength down to the order of 0.3 Mt CO2 yr-1 can be resolved in an urban environment (when limited by instrument noise only), hence leaving significant margin for additional errors.
Sebastian Donner, Jonas Kuhn, Michel Van Roozendael, Alkiviadis Bais, Steffen Beirle, Tim Bösch, Kristof Bognar, Ilya Bruchkouski, Ka Lok Chan, Steffen Dörner, Theano Drosoglou, Caroline Fayt, Udo Frieß, François Hendrick, Christian Hermans, Junli Jin, Ang Li, Jianzhong Ma, Enno Peters, Gaia Pinardi, Andreas Richter, Stefan F. Schreier, André Seyler, Kimberly Strong, Jan-Lukas Tirpitz, Yang Wang, Pinhua Xie, Jin Xu, Xiaoyi Zhao, and Thomas Wagner
Atmos. Meas. Tech., 13, 685–712,Short summary
The calibration of the elevation angles of MAX-DOAS instruments is important for the correct interpretation of such MAX-DOAS measurements. We present and evaluate different methods for the elevation calibration of MAX-DOAS instruments which were applied during the CINDI-2 field campaign.
Jonas Simon Wilzewski, Anke Roiger, Johan Strandgren, Jochen Landgraf, Dietrich G. Feist, Voltaire A. Velazco, Nicholas M. Deutscher, Isamu Morino, Hirofumi Ohyama, Yao Té, Rigel Kivi, Thorsten Warneke, Justus Notholt, Manvendra Dubey, Ralf Sussmann, Markus Rettinger, Frank Hase, Kei Shiomi, and André Butz
Atmos. Meas. Tech., 13, 731–745,Short summary
Through spectral degradation of GOSAT measurements in the 1.6 and 2.0 μm spectral bands, we mimic a single-band, passive satellite sensor for monitoring of CO2 emissions at fine spatial scales. We compare retrievals of XCO2 from these bands to TCCON and native GOSAT retrievals. At spectral resolutions near 1.3 nm, XCO2 retrievals from both bands show promising performance, but the 2.0 μm band is favorable due to better noise performance and the potential to retrieve some aerosol information.
Samuel Quesada-Ruiz, Jean-Luc Attié, William A. Lahoz, Rachid Abida, Philippe Ricaud, Laaziz El Amraoui, Régina Zbinden, Andrea Piacentini, Mathieu Joly, Henk Eskes, Arjo Segers, Lyana Curier, Johan de Haan, Jukka Kujanpää, Albert Christiaan Plechelmus Oude Nijhuis, Johanna Tamminen, Renske Timmermans, and Pepijn Veefkind
Atmos. Meas. Tech., 13, 131–152,
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Measurements of upper tropospheric-lower stratospheric water vapor amounts in the tropics were made using the 1400 and 1900nm water vapor bands present in airborne solar spectral irradiance data. These were validated with radiative transfer modeling using in situ profiles of water vapor, temperature, and pressure. An approach to extending these types of measurements from aircraft altitudes to the top of the atmosphere to infer stratospheric water vapor amount is outlined.
Measurements of upper tropospheric-lower stratospheric water vapor amounts in the tropics were...