Articles | Volume 15, issue 8
https://doi.org/10.5194/amt-15-2417-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-15-2417-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Quantifying the coastal urban surface layer structure using distributed temperature sensing in Helsinki, Finland
Sasu Karttunen
CORRESPONDING AUTHOR
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Ewan O'Connor
Finnish Meteorological Institute, Helsinki, Finland
Olli Peltola
Finnish Meteorological Institute, Helsinki, Finland
Research Infrastructure Services, Natural Resources Institute Finland, Helsinki, Finland
Leena Järvi
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Helsinki Institute of Sustainability Science, Faculty of Science, University of Helsinki, Helsinki, Finland
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This paper presents PALM-SLUrb, a single-layer urban canopy model for the PALM system, designed to simulate urban-atmosphere interactions without resolving flow around individual buildings. The model is described in detail and evaluated against grid-resolved urban canopy simulations, demonstrating its ability to model urban surfaces accurately. By bridging the gap between computational efficiency and physical detail, PALM-SLUrb broadens PALM's potential for urban climate research.
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High-resolution modelling is needed to solve the aerosol concentrations in a complex urban area. Here, the performance of an aerosol module within the PALM model to simulate the detailed horizontal and vertical distribution of aerosol particles is studied. Further, sensitivity to the meteorological and aerosol boundary conditions is assessed using both model and observation data. The horizontal distribution is sensitive to the wind speed and stability, and the vertical to the wind direction.
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Qing Ying, Benjamin Poulter, Jennifer D. Watts, Kyle A. Arndt, Anna-Maria Virkkala, Lori Bruhwiler, Youmi Oh, Brendan M. Rogers, Susan M. Natali, Hilary Sullivan, Amanda Armstrong, Eric J. Ward, Luke D. Schiferl, Clayton D. Elder, Olli Peltola, Annett Bartsch, Ankur R. Desai, Eugénie Euskirchen, Mathias Göckede, Bernhard Lehner, Mats B. Nilsson, Matthias Peichl, Oliver Sonnentag, Eeva-Stiina Tuittila, Torsten Sachs, Aram Kalhori, Masahito Ueyama, and Zhen Zhang
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Biogeosciences, 22, 2133–2161, https://doi.org/10.5194/bg-22-2133-2025, https://doi.org/10.5194/bg-22-2133-2025, 2025
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Natalie E. Theeuwes, Janet F. Barlow, Antti Mannisenaho, Denise Hertwig, Ewan O'Connor, and Alan Robins
Atmos. Meas. Tech., 18, 1355–1371, https://doi.org/10.5194/amt-18-1355-2025, https://doi.org/10.5194/amt-18-1355-2025, 2025
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A Doppler lidar was placed in a highly built-up area in London to measure wakes from tall buildings during a period of 1 year. We were able to detect wakes and assess their dependence on wind speed, wind direction, and atmospheric stability.
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Biogeosciences, 22, 1277–1300, https://doi.org/10.5194/bg-22-1277-2025, https://doi.org/10.5194/bg-22-1277-2025, 2025
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Zen Mariani, Sara M. Morris, Taneil Uttal, Elena Akish, Robert Crawford, Laura Huang, Jonathan Day, Johanna Tjernström, Øystein Godøy, Lara Ferrighi, Leslie M. Hartten, Jareth Holt, Christopher J. Cox, Ewan O'Connor, Roberta Pirazzini, Marion Maturilli, Giri Prakash, James Mather, Kimberly Strong, Pierre Fogal, Vasily Kustov, Gunilla Svensson, Michael Gallagher, and Brian Vasel
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Viet Le, Hannah Lobo, Ewan J. O'Connor, and Ville Vakkari
Atmos. Meas. Tech., 17, 921–941, https://doi.org/10.5194/amt-17-921-2024, https://doi.org/10.5194/amt-17-921-2024, 2024
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This study offers a long-term overview of aerosol particle depolarization ratio at the wavelength of 1565 nm obtained from vertical profiling measurements by Halo Doppler lidars during 4 years at four different locations across Finland. Our observations support the long-term usage of Halo Doppler lidar depolarization ratio such as the detection of aerosols that may pose a safety risk for aviation. Long-range Saharan dust transport and pollen transport are also showcased here.
Joyson Ahongshangbam, Liisa Kulmala, Jesse Soininen, Yasmin Frühauf, Esko Karvinen, Yann Salmon, Anna Lintunen, Anni Karvonen, and Leena Järvi
Biogeosciences, 20, 4455–4475, https://doi.org/10.5194/bg-20-4455-2023, https://doi.org/10.5194/bg-20-4455-2023, 2023
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Urban vegetation is important for removing urban CO2 emissions and cooling. We studied the response of urban trees' functions (photosynthesis and transpiration) to a heatwave and drought at four urban green areas in the city of Helsinki. We found that tree water use was increased during heatwave and drought periods, but there was no change in the photosynthesis rates. The heat and drought conditions were severe at the local scale but were not excessive enough to restrict urban trees' functions.
Jani Strömberg, Xiaoyu Li, Mona Kurppa, Heino Kuuluvainen, Liisa Pirjola, and Leena Järvi
Atmos. Chem. Phys., 23, 9347–9364, https://doi.org/10.5194/acp-23-9347-2023, https://doi.org/10.5194/acp-23-9347-2023, 2023
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We conclude that with low wind speeds, solar radiation has a larger decreasing effect (53 %) on pollutant concentrations than aerosol processes (18 %). Additionally, our results showed that with solar radiation included, pollutant concentrations were closer to observations (−13 %) than with only aerosol processes (+98 %). This has implications when planning simulations under calm conditions such as in our case and when deciding whether or not simulations need to include these processes.
Maria Filioglou, Ari Leskinen, Ville Vakkari, Ewan O'Connor, Minttu Tuononen, Pekko Tuominen, Samuli Laukkanen, Linnea Toiviainen, Annika Saarto, Xiaoxia Shang, Petri Tiitta, and Mika Komppula
Atmos. Chem. Phys., 23, 9009–9021, https://doi.org/10.5194/acp-23-9009-2023, https://doi.org/10.5194/acp-23-9009-2023, 2023
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Pollen impacts climate and public health, and it can be detected in the atmosphere by lidars which measure the linear particle depolarization ratio (PDR), a shape-relevant optical parameter. As aerosols also cause depolarization, surface aerosol and pollen observations were combined with measurements from ground-based lidars operating at different wavelengths to determine the optical properties of birch and pine pollen and quantify their relative contribution to the PDR.
Yingqi Zheng, Minttu Havu, Huizhi Liu, Xueling Cheng, Yifan Wen, Hei Shing Lee, Joyson Ahongshangbam, and Leena Järvi
Geosci. Model Dev., 16, 4551–4579, https://doi.org/10.5194/gmd-16-4551-2023, https://doi.org/10.5194/gmd-16-4551-2023, 2023
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The performance of the Surface Urban Energy and Water Balance Scheme (SUEWS) is evaluated against the observed surface exchanges (fluxes) of heat and carbon dioxide in a densely built neighborhood in Beijing. The heat flux modeling is noticeably improved by using the observed maximum conductance and by optimizing the vegetation phenology modeling. SUEWS also performs well in simulating carbon dioxide flux.
Gillian Young McCusker, Jutta Vüllers, Peggy Achtert, Paul Field, Jonathan J. Day, Richard Forbes, Ruth Price, Ewan O'Connor, Michael Tjernström, John Prytherch, Ryan Neely III, and Ian M. Brooks
Atmos. Chem. Phys., 23, 4819–4847, https://doi.org/10.5194/acp-23-4819-2023, https://doi.org/10.5194/acp-23-4819-2023, 2023
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In this study, we show that recent versions of two atmospheric models – the Unified Model and Integrated Forecasting System – overestimate Arctic cloud fraction within the lower troposphere by comparison with recent remote-sensing measurements made during the Arctic Ocean 2018 expedition. The overabundance of cloud is interlinked with the modelled thermodynamic structure, with strong negative temperature biases coincident with these overestimated cloud layers.
Pyry Pentikäinen, Ewan J. O'Connor, and Pablo Ortiz-Amezcua
Geosci. Model Dev., 16, 2077–2094, https://doi.org/10.5194/gmd-16-2077-2023, https://doi.org/10.5194/gmd-16-2077-2023, 2023
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We used Doppler lidar to evaluate the wind profiles generated by a weather forecast model. We first compared the Doppler lidar observations with co-located radiosonde profiles, and they agree well. The model performs best over marine and coastal locations. Larger errors were seen in locations where the surface was more complex, especially in the wind direction. Our results show that Doppler lidar is a suitable instrument for evaluating the boundary layer wind profiles in atmospheric models.
Konstantinos Matthaios Doulgeris, Ville Vakkari, Ewan J. O'Connor, Veli-Matti Kerminen, Heikki Lihavainen, and David Brus
Atmos. Chem. Phys., 23, 2483–2498, https://doi.org/10.5194/acp-23-2483-2023, https://doi.org/10.5194/acp-23-2483-2023, 2023
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We investigated how different long-range-transported air masses can affect the microphysical properties of low-level clouds in a clean subarctic environment. A connection was revealed. Higher values of cloud droplet number concentrations were related to continental air masses, whereas the lowest values of number concentrations were related to marine air masses. These were characterized by larger cloud droplets. Clouds in all regions were sensitive to increases in cloud number concentration.
Simone Kotthaus, Juan Antonio Bravo-Aranda, Martine Collaud Coen, Juan Luis Guerrero-Rascado, Maria João Costa, Domenico Cimini, Ewan J. O'Connor, Maxime Hervo, Lucas Alados-Arboledas, María Jiménez-Portaz, Lucia Mona, Dominique Ruffieux, Anthony Illingworth, and Martial Haeffelin
Atmos. Meas. Tech., 16, 433–479, https://doi.org/10.5194/amt-16-433-2023, https://doi.org/10.5194/amt-16-433-2023, 2023
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Profile observations of the atmospheric boundary layer now allow for layer heights and characteristics to be derived at high temporal and vertical resolution. With novel high-density ground-based remote-sensing measurement networks emerging, horizontal information content is also increasing. This review summarises the capabilities and limitations of various sensors and retrieval algorithms which need to be considered during the harmonisation of data products for high-impact applications.
Mathew Lipson, Sue Grimmond, Martin Best, Winston T. L. Chow, Andreas Christen, Nektarios Chrysoulakis, Andrew Coutts, Ben Crawford, Stevan Earl, Jonathan Evans, Krzysztof Fortuniak, Bert G. Heusinkveld, Je-Woo Hong, Jinkyu Hong, Leena Järvi, Sungsoo Jo, Yeon-Hee Kim, Simone Kotthaus, Keunmin Lee, Valéry Masson, Joseph P. McFadden, Oliver Michels, Wlodzimierz Pawlak, Matthias Roth, Hirofumi Sugawara, Nigel Tapper, Erik Velasco, and Helen Claire Ward
Earth Syst. Sci. Data, 14, 5157–5178, https://doi.org/10.5194/essd-14-5157-2022, https://doi.org/10.5194/essd-14-5157-2022, 2022
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We describe a new openly accessible collection of atmospheric observations from 20 cities around the world, capturing 50 site years. The observations capture local meteorology (temperature, humidity, wind, etc.) and the energy fluxes between the land and atmosphere (e.g. radiation and sensible and latent heat fluxes). These observations can be used to improve our understanding of urban climate processes and to test the accuracy of urban climate models.
Jenna Ritvanen, Ewan O'Connor, Dmitri Moisseev, Raisa Lehtinen, Jani Tyynelä, and Ludovic Thobois
Atmos. Meas. Tech., 15, 6507–6519, https://doi.org/10.5194/amt-15-6507-2022, https://doi.org/10.5194/amt-15-6507-2022, 2022
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Doppler lidars and weather radars provide accurate wind measurements, with Doppler lidar usually performing better in dry weather conditions and weather radar performing better when there is precipitation. Operating both instruments together should therefore improve the overall performance. We investigate how well a co-located Doppler lidar and X-band radar perform with respect to various weather conditions, including changes in horizontal visibility, cloud altitude, and precipitation.
Minttu Havu, Liisa Kulmala, Pasi Kolari, Timo Vesala, Anu Riikonen, and Leena Järvi
Biogeosciences, 19, 2121–2143, https://doi.org/10.5194/bg-19-2121-2022, https://doi.org/10.5194/bg-19-2121-2022, 2022
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The carbon sequestration potential of two street tree species and the soil beneath them was quantified with the urban land surface model SUEWS and the soil carbon model Yasso. The street tree plantings turned into a modest sink of carbon from the atmosphere after 14 years. Overall, the results indicate the importance of soil in urban carbon sequestration estimations, as soil respiration exceeded the carbon uptake in the early phase, due to the high initial carbon loss from the soil.
Jutta Kesti, John Backman, Ewan J. O'Connor, Anne Hirsikko, Eija Asmi, Minna Aurela, Ulla Makkonen, Maria Filioglou, Mika Komppula, Hannele Korhonen, and Heikki Lihavainen
Atmos. Chem. Phys., 22, 481–503, https://doi.org/10.5194/acp-22-481-2022, https://doi.org/10.5194/acp-22-481-2022, 2022
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In this study we combined aerosol particle measurements at the surface with a scanning Doppler lidar providing vertical profiles of the atmosphere to study the effect of different boundary layer conditions on aerosol particle properties in the understudied Arabian Peninsula region. The instrumentation used in this study enabled us to identify periods when pollution from remote sources was mixed down to the surface and initiated new particle formation in the growing boundary layer.
Moritz Lange, Henri Suominen, Mona Kurppa, Leena Järvi, Emilia Oikarinen, Rafael Savvides, and Kai Puolamäki
Geosci. Model Dev., 14, 7411–7424, https://doi.org/10.5194/gmd-14-7411-2021, https://doi.org/10.5194/gmd-14-7411-2021, 2021
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This study aims to replicate computationally expensive high-resolution large-eddy simulations (LESs) with regression models to simulate urban air quality and pollutant dispersion. The model development, including feature selection, model training and cross-validation, and detection of concept drift, has been described in detail. Of the models applied, log-linear regression shows the best performance. A regression model can replace LES unless high accuracy is needed.
Anna Franck, Dmitri Moisseev, Ville Vakkari, Matti Leskinen, Janne Lampilahti, Veli-Matti Kerminen, and Ewan O'Connor
Atmos. Meas. Tech., 14, 7341–7353, https://doi.org/10.5194/amt-14-7341-2021, https://doi.org/10.5194/amt-14-7341-2021, 2021
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We proposed a method to derive a convective boundary layer height, using insects in radar observations, and we investigated the consistency of these retrievals among different radar frequencies (5, 35 and 94 GHz). This method can be applied to radars at other measurement stations and serve as additional way to estimate the boundary layer height during summer. The entrainment zone was also observed by the 5 GHz radar above the boundary layer in the form of a Bragg scatter layer.
Xiaoxia Shang, Tero Mielonen, Antti Lipponen, Elina Giannakaki, Ari Leskinen, Virginie Buchard, Anton S. Darmenov, Antti Kukkurainen, Antti Arola, Ewan O'Connor, Anne Hirsikko, and Mika Komppula
Atmos. Meas. Tech., 14, 6159–6179, https://doi.org/10.5194/amt-14-6159-2021, https://doi.org/10.5194/amt-14-6159-2021, 2021
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The long-range-transported smoke particles from a Canadian wildfire event were observed with a multi-wavelength Raman polarization lidar and a ceilometer over Kuopio, Finland, in June 2019. The optical properties and the mass concentration estimations were reported for such aged smoke aerosols over northern Europe.
Kyle B. Delwiche, Sara Helen Knox, Avni Malhotra, Etienne Fluet-Chouinard, Gavin McNicol, Sarah Feron, Zutao Ouyang, Dario Papale, Carlo Trotta, Eleonora Canfora, You-Wei Cheah, Danielle Christianson, Ma. Carmelita R. Alberto, Pavel Alekseychik, Mika Aurela, Dennis Baldocchi, Sheel Bansal, David P. Billesbach, Gil Bohrer, Rosvel Bracho, Nina Buchmann, David I. Campbell, Gerardo Celis, Jiquan Chen, Weinan Chen, Housen Chu, Higo J. Dalmagro, Sigrid Dengel, Ankur R. Desai, Matteo Detto, Han Dolman, Elke Eichelmann, Eugenie Euskirchen, Daniela Famulari, Kathrin Fuchs, Mathias Goeckede, Sébastien Gogo, Mangaliso J. Gondwe, Jordan P. Goodrich, Pia Gottschalk, Scott L. Graham, Martin Heimann, Manuel Helbig, Carole Helfter, Kyle S. Hemes, Takashi Hirano, David Hollinger, Lukas Hörtnagl, Hiroki Iwata, Adrien Jacotot, Gerald Jurasinski, Minseok Kang, Kuno Kasak, John King, Janina Klatt, Franziska Koebsch, Ken W. Krauss, Derrick Y. F. Lai, Annalea Lohila, Ivan Mammarella, Luca Belelli Marchesini, Giovanni Manca, Jaclyn Hatala Matthes, Trofim Maximov, Lutz Merbold, Bhaskar Mitra, Timothy H. Morin, Eiko Nemitz, Mats B. Nilsson, Shuli Niu, Walter C. Oechel, Patricia Y. Oikawa, Keisuke Ono, Matthias Peichl, Olli Peltola, Michele L. Reba, Andrew D. Richardson, William Riley, Benjamin R. K. Runkle, Youngryel Ryu, Torsten Sachs, Ayaka Sakabe, Camilo Rey Sanchez, Edward A. Schuur, Karina V. R. Schäfer, Oliver Sonnentag, Jed P. Sparks, Ellen Stuart-Haëntjens, Cove Sturtevant, Ryan C. Sullivan, Daphne J. Szutu, Jonathan E. Thom, Margaret S. Torn, Eeva-Stiina Tuittila, Jessica Turner, Masahito Ueyama, Alex C. Valach, Rodrigo Vargas, Andrej Varlagin, Alma Vazquez-Lule, Joseph G. Verfaillie, Timo Vesala, George L. Vourlitis, Eric J. Ward, Christian Wille, Georg Wohlfahrt, Guan Xhuan Wong, Zhen Zhang, Donatella Zona, Lisamarie Windham-Myers, Benjamin Poulter, and Robert B. Jackson
Earth Syst. Sci. Data, 13, 3607–3689, https://doi.org/10.5194/essd-13-3607-2021, https://doi.org/10.5194/essd-13-3607-2021, 2021
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Methane is an important greenhouse gas, yet we lack knowledge about its global emissions and drivers. We present FLUXNET-CH4, a new global collection of methane measurements and a critical resource for the research community. We use FLUXNET-CH4 data to quantify the seasonality of methane emissions from freshwater wetlands, finding that methane seasonality varies strongly with latitude. Our new database and analysis will improve wetland model accuracy and inform greenhouse gas budgets.
Toprak Aslan, Olli Peltola, Andreas Ibrom, Eiko Nemitz, Üllar Rannik, and Ivan Mammarella
Atmos. Meas. Tech., 14, 5089–5106, https://doi.org/10.5194/amt-14-5089-2021, https://doi.org/10.5194/amt-14-5089-2021, 2021
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Vertical turbulent fluxes of gases measured by the eddy covariance (EC) technique are subject to high-frequency losses. There are different methods used to describe this low-pass filtering effect and to correct the measured fluxes. In this study, we analysed the systematic uncertainty related to this correction for various attenuation and signal-to-noise ratios. A new and robust transfer function method is finally proposed.
Olli Peltola, Toprak Aslan, Andreas Ibrom, Eiko Nemitz, Üllar Rannik, and Ivan Mammarella
Atmos. Meas. Tech., 14, 5071–5088, https://doi.org/10.5194/amt-14-5071-2021, https://doi.org/10.5194/amt-14-5071-2021, 2021
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Gas fluxes measured by the eddy covariance (EC) technique are subject to filtering due to non-ideal instrumentation. For linear first-order systems this filtering causes also a time lag between vertical wind speed and gas signal which is additional to the gas travel time in the sampling line. The effect of this additional time lag on EC fluxes is ignored in current EC data processing routines. Here we show that this oversight biases EC fluxes and hence propose an approach to rectify this bias.
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
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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.
Steven Compernolle, Athina Argyrouli, Ronny Lutz, Maarten Sneep, Jean-Christopher Lambert, Ann Mari Fjæraa, Daan Hubert, Arno Keppens, Diego Loyola, Ewan O'Connor, Fabian Romahn, Piet Stammes, Tijl Verhoelst, and Ping Wang
Atmos. Meas. Tech., 14, 2451–2476, https://doi.org/10.5194/amt-14-2451-2021, https://doi.org/10.5194/amt-14-2451-2021, 2021
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The high-resolution satellite Sentinel-5p TROPOMI observes several atmospheric gases. To account for cloud interference with the observations, S5P cloud data products (CLOUD OCRA/ROCINN_CAL, OCRA/ROCINN_CRB, and FRESCO) provide vital input: cloud fraction, cloud height, and cloud optical thickness. Here, S5P cloud parameters are validated by comparing with other satellite sensors (VIIRS, MODIS, and OMI) and with ground-based CloudNet data. The agreement depends on product type and cloud height.
Olli Peltola, Karl Lapo, Ilkka Martinkauppi, Ewan O'Connor, Christoph K. Thomas, and Timo Vesala
Atmos. Meas. Tech., 14, 2409–2427, https://doi.org/10.5194/amt-14-2409-2021, https://doi.org/10.5194/amt-14-2409-2021, 2021
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We evaluated the suitability of fiber-optic distributed temperature sensing (DTS) for observing spatial (>25 cm) and temporal (>1 s) details of airflow within and above forests. The DTS measurements could discern up to third-order moments of the flow and observe spatial details of coherent flow motions. Similar measurements are not possible with more conventional measurement techniques. Hence, the DTS measurements will provide key insights into flows close to roughness elements, e.g. trees.
Elisa Vainio, Olli Peltola, Ville Kasurinen, Antti-Jussi Kieloaho, Eeva-Stiina Tuittila, and Mari Pihlatie
Biogeosciences, 18, 2003–2025, https://doi.org/10.5194/bg-18-2003-2021, https://doi.org/10.5194/bg-18-2003-2021, 2021
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We studied forest floor methane exchange over an area of 10 ha in a boreal pine forest. The results demonstrate high spatial variability in soil moisture and consequently in the methane flux. We detected wet patches emitting high amounts of methane in the early summer; however, these patches turned to methane uptake in the autumn. We concluded that the small-scale spatial variability of the boreal forest methane flux highlights the importance of soil chamber placement in similar studies.
Peggy Achtert, Ewan J. O'Connor, Ian M. Brooks, Georgia Sotiropoulou, Matthew D. Shupe, Bernhard Pospichal, Barbara J. Brooks, and Michael Tjernström
Atmos. Chem. Phys., 20, 14983–15002, https://doi.org/10.5194/acp-20-14983-2020, https://doi.org/10.5194/acp-20-14983-2020, 2020
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We present observations of precipitating and non-precipitating Arctic liquid and mixed-phase clouds during a research cruise along the Russian shelf in summer and autumn of 2014. Active remote-sensing observations, radiosondes, and auxiliary measurements are combined in the synergistic Cloudnet retrieval. Cloud properties are analysed with respect to cloud-top temperature and boundary layer structure. About 8 % of all liquid clouds show a liquid water path below the infrared black body limit.
Mona Kurppa, Pontus Roldin, Jani Strömberg, Anna Balling, Sasu Karttunen, Heino Kuuluvainen, Jarkko V. Niemi, Liisa Pirjola, Topi Rönkkö, Hilkka Timonen, Antti Hellsten, and Leena Järvi
Geosci. Model Dev., 13, 5663–5685, https://doi.org/10.5194/gmd-13-5663-2020, https://doi.org/10.5194/gmd-13-5663-2020, 2020
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High-resolution modelling is needed to solve the aerosol concentrations in a complex urban area. Here, the performance of an aerosol module within the PALM model to simulate the detailed horizontal and vertical distribution of aerosol particles is studied. Further, sensitivity to the meteorological and aerosol boundary conditions is assessed using both model and observation data. The horizontal distribution is sensitive to the wind speed and stability, and the vertical to the wind direction.
Cited articles
Andreas, E. L., Hill, R. J., Gosz, J. R., Moore, D. I., Otto, W. D., and Sarma, A. D.: Statistics of surface-layer turbulence over terrain with metre-scale heterogeneity, Bound.-Lay. Meteorol., 86, 379–408,
https://doi.org/10.1023/A:1000609131683, 1998. a, b
Aubinet, M., Grelle, A., Ibrom, A., Rannik, Ü., Moncrieff, J., Foken, T., Kowalski, A. S., Martin, P. H., Berbigier, P., Bernhofer, C., Clement, R., Elbers, J., Granier, A., Grünwald, T., Morgenstern, K., Pilegaard, K., Rebmann, C., Snijders, W., Valentini, R., and Vesala, T.: Estimates of the Annual Net Carbon and Water Exchange of Forests: The EUROFLUX Methodology, Adv. Ecol. Res., 30, 113–175,
https://doi.org/10.1016/S0065-2504(08)60018-5, 1999. a
Aubinet, M., Vesala, T., and Papale, D. (Eds.): Eddy Covariance, 1st edn., Springer, Dordrecht, https://doi.org/10.1007/978-94-007-2351-1, 2012. a
Baars, W. J., Talluru, K. M., Hutchins, N., and Marusic, I.: Wavelet analysis of wall turbulence to study large-scale modulation of small scales,
Exp. Fluids, 56, 188, https://doi.org/10.1007/s00348-015-2058-8, 2015. a
Barlow, J. F.: Progress in observing and modelling the urban boundary layer, Urban Climate, 10, 216–240, https://doi.org/10.1016/j.uclim.2014.03.011, 2014. a, b
Bradley, S., Barlow, J., Lally, J., and Halois, C.: A sodar for profiling in a spatially inhomogeneous urban environment, Meteorol. Z., 24,
615–624, https://doi.org/10.1127/metz/2015/0657, 2015. a
Businger, J. A.: A Note on the Businger-Dyer Profiles, Topics in Micrometeorology. A Festschrift for Arch Dyer, Springer, Dordrecht, 145–151,
https://doi.org/10.1007/978-94-009-2935-7_11, 1988. a
Cheng, H., Hayden, P., Robins, A. G., and Castro, I. P.: Flow over cube arrays of different packing densities, J. Wind Eng. Ind. Aerod., 95, 715–740, https://doi.org/10.1016/J.JWEIA.2007.01.004, 2007. a
City of Helsinki: 3D city model of the city of Helsinki, City of Helsinki, https://hri.fi/data/en_GB/dataset/helsingin-3d-kaupunkimalli (last access: 23 November 2020),
2017. a
de Giesen, N. V., Steele-Dunne, S. C., Jansen, J., Hoes, O., Hausner, M. B.,
Tyler, S., and Selker, J.: Double-Ended Calibration of Fiber-Optic Raman
Spectra Distributed Temperature Sensing Data, Sensors, 12, 5471–5485,
https://doi.org/10.3390/S120505471, 2012. a
de Jong, S. A. P., Slingerland, J. D., and van de Giesen, N. C.: Fiber optic distributed temperature sensing for the determination of air temperature, Atmos. Meas. Tech., 8, 335–339, https://doi.org/10.5194/amt-8-335-2015, 2015. a, b, c, d
Emeis, S.: Surface-Based Remote Sensing of the Atmospheric Boundary Layer,
Atmospheric and Oceanographic Sciences Library, Springer, Dordrecht,
https://doi.org/10.1007/978-90-481-9340-0, 2011. a
Epps, B. P. and Krivitzky, E. M.: Singular value decomposition of noisy data: noise filtering, Exp. Fluids, 60, 126,
https://doi.org/10.1007/s00348-019-2768-4, 2019. a, b, c, d
Farahani, M. A. and Gogolla, T.: Spontaneous Raman scattering in optical fibers with modulated probe light for distributed temperature Raman remote sensing, J. Lightwave Technol., 17, 1379–1391, https://doi.org/10.1109/50.779159, 1999. a
Farge, M.: Wavelet Transforms and their Applications to Turbulence, Annu. Rev. Fluid Mech., 24, 395–458, https://doi.org/10.1146/annurev.fl.24.010192.002143, 1992. a, b
Foken, T.: Micrometeorology, 2nd edn., Springer-Verlag, Berlin, Heidelberg,
https://doi.org/10.1007/978-3-642-25440-6, 2017. a
Fritz, A. M., Lapo, K., Freundorfer, A., Linhardt, T., and Thomas, C. K.:
Revealing the Morning Transition in the Mountain Boundary Layer Using
Fiber-Optic Distributed Temperature Sensing, Geophys. Res. Lett.,
48, e2020GL092238, https://doi.org/10.1029/2020GL092238, 2021. a
Gahmberg, M., Savijärvi, H., and Leskinen, M.: The influence of synoptic scale flow on sea breeze induced surface winds and calm zones, Tellus A, 62, 209–217, https://doi.org/10.1111/J.1600-0870.2009.00423.X, 2010. a
Garratt, J. R.: The internal boundary layer – A review, Bound.-Lay. Meteorol., 50, 171–203, https://doi.org/10.1007/BF00120524, 1990. a
Hausner, M. B., Suárez, F., Glander, K. E., van de Giesen, N., Selker, J. S., and Tyler, S. W.: Calibrating Single-Ended Fiber-Optic Raman Spectra Distributed Temperature Sensing Data, Sensors, 11, 10859–10879, https://doi.org/10.3390/S111110859, 2011. a
Higgins, C. W., Wing, M. G., Kelley, J., Sayde, C., Burnett, J., and Holmes, H. A.: A high resolution measurement of the morning ABL transition using distributed temperature sensing and an unmanned aircraft system, Environ. Fluid Mech., 18, 683–693, https://doi.org/10.1007/S10652-017-9569-1, 2018. a
Izett, J. G., Schilperoort, B., Coenders-Gerrits, M., Baas, P., Bosveld, F. C., and van de Wiel, B. J.: Missed Fog?: On the Potential of Obtaining
Observations at Increased Resolution During Shallow Fog Events,
Bound.-Lay. Meteorol., 173, 289–309, https://doi.org/10.1007/s10546-019-00462-3,
2019. a, b
Järvi, L., Hannuniemi, H., Hussein, T., Junninen, H., Aalto, P., Keronen, P., Kulmala, M., Keronen, P., Hillamo, R., Mäkelä, T., Siivola, E., and Vesala, T.: The urban measurement station SMEAR III: Continuous monitoring of air pollution and surface-atmosphere interactions in Helsinki, Finland, Boreal Environ. Res., 14, 1797–2469, 2009. a
Kaimal, J. C. and Finnigan, J. J.: Atmospheric Boundary Layer Flows: Their Structure and Measurement, Oxford University Press, https://doi.org/10.1093/oso/9780195062397.001.0001, 1994. a
Karttunen, S.: Python scripts for analysing distributed temperature sensing (DTS) measurements from Helsinki, Finland, Zenodo [code], https://doi.org/10.5281/zenodo.5793334, 2021a. a
Karttunen, S.: Supplementary data for analysing distributed temperature
sensing (DTS) measurements from Helsinki, Finland, Zenodo [data set],
https://doi.org/10.5281/zenodo.5793838, 2021b. a
Keller, C. A., Huwald, H., Vollmer, M. K., Wenger, A., Hill, M., Parlange, M. B., and Reimann, S.: Fiber optic distributed temperature sensing for the determination of the nocturnal atmospheric boundary layer height, Atmos. Meas. Tech., 4, 143–149, https://doi.org/10.5194/amt-4-143-2011, 2011. a
Kotthaus, S., Haeffelin, M., Drouin, M.-A., Dupont, J.-C., Grimmond, S., Haefele, A., Hervo, M., Poltera, Y., and Wiegner, M.: Tailored Algorithms for the Detection of the Atmospheric Boundary Layer Height from Common Automatic Lidars and Ceilometers (ALC), Remote Sens., 12, 3259, https://doi.org/10.3390/rs12193259, 2020. a
Lareau, N. P. and Horel, J. D.: Dynamically Induced Displacements of a
Persistent Cold-Air Pool, Bound.-Lay. Meteorol., 154,
291–316, https://doi.org/10.1007/S10546-014-9968-5, 2015. a
Lenschow, D. H., Wulfmeyer, V., and Senff, C.: Measuring Second- through Fourth-Order Moments in Noisy Data, J. Atmos. Ocean. Tech., 17, 1330–1347,
https://doi.org/10.1175/1520-0426(2000)017<1330:MSTFOM>2.0.CO;2, 2000. a
Liu, X., Tsukamoto, O., Oikawa, T., and Ohtaki, E.: A study of correlations of scalar quantities in the atmospheric surface layer, Bound.-Lay. Meteorol., 87, 499–508, https://doi.org/10.1023/A:1000947709324, 1998. a, b
Liu, Y., Liang, X. S., and Weisberg, R. H.: Rectification of the bias in the
wavelet power spectrum, J. Atmos. Ocean. Tech., 24,
2093–2102, https://doi.org/10.1175/2007JTECHO511.1, 2007. a
Mahrt, L., Pfister, L., and Thomas, C. K.: Small-Scale Variability in the
Nocturnal Boundary Layer, Bound.-Lay. Meteorol., 174, 81–98,
https://doi.org/10.1007/S10546-019-00476-X, 2020. a
Manninen, A., Marke, T., Tuononen, M., and O'Connor, E.: Atmospheric boundary
layer classification with Doppler lidar, J. Geophys. Res., 123, 8172–8189, https://doi.org/10.1029/2017JD028169, 2018. a
Maronga, B. and Reuder, J.: On the formulation and universality of Monin-Obukhov similarity functions for mean gradients and standard deviations
in the unstable surface layer: Results from surface-layer-resolving
large-eddy simulations, J. Atmos. Sci., 74, 989–1010,
https://doi.org/10.1175/JAS-D-16-0186.1, 2017. a, b
Monin, A. S. and Obukhov, A. M.: Basic laws of turbulent mixing in the surface layer of the atmosphere, originally published in: Tr. Akad. Nauk SSSR Geophiz. Inst, 24, 163–187, 1954. a
Nordbo, A., Järvi, L., Haapanala, S., Moilanen, J., and Vesala, T.:
Intra-City Variation in Urban Morphology and Turbulence Structure in
Helsinki, Finland, Bound.-Lay. Meteorol., 146, 469–496,
https://doi.org/10.1007/s10546-012-9773-y, 2013. a
Panofsky, H. A., Tennekes, H., Lenschow, D. H., and Wyngaard, J. C.: The
characteristics of turbulent velocity components in the surface layer under
convective conditions, Bound.-Lay. Meteorol., 11, 355–361,
https://doi.org/10.1007/BF02186086, 1977. a, b
Päschke, E., Leinweber, R., and Lehmann, V.: An assessment of the performance of a 1.5 µm Doppler lidar for operational vertical wind profiling based on a 1-year trial, Atmos. Meas. Tech., 8, 2251–2266, https://doi.org/10.5194/amt-8-2251-2015, 2015. a
Peltola, O.: Dataset containing DTS-data used in Karttunen et al. “Quantifying coastal urban surface layer structure using distributed temperature sensing in Helsinki, Finland”, Zenodo [data set], https://doi.org/10.5281/zenodo.5796181, 2021. a
Peltola, O., Lapo, K., Martinkauppi, I., O'Connor, E., Thomas, C. K., and Vesala, T.: Suitability of fibre-optic distributed temperature sensing for revealing mixing processes and higher-order moments at the forest–air interface, Atmos. Meas. Tech., 14, 2409–2427, https://doi.org/10.5194/amt-14-2409-2021, 2021. a, b, c, d, e, f
Pfister, L., Sigmund, A., Olesch, J., and Thomas, C. K.: Nocturnal
Near-Surface Temperature, but not Flow Dynamics, can be Predicted by
Microtopography in a Mid-Range Mountain Valley, Bound.-Lay. Meteorol.,
165, 333–348, https://doi.org/10.1007/S10546-017-0281-Y, 2017. a
Pfister, L., Lapo, K., Sayde, C., Selker, J., Mahrt, L., and Thomas, C. K.: Classifying the nocturnal atmospheric boundary layer into temperature and flow regimes, Q. J. Roy. Meteor. Soc., 145, 1515–1534, https://doi.org/10.1002/QJ.3508, 2019. a
Rotach, M. W.: On the influence of the urban roughness sublayer on turbulence and dispersion, Atmos. Environ., 33, 4001–4008,
https://doi.org/10.1016/S1352-2310(99)00141-7, 1999. a, b, c
Savijärvi, H.: The Sea Breeze and Urban Heat Island Circulation In A
Numerical Model, Geophysica, 21, 115–126, 1985. a
Savijärvi, H., Niemelä, S., and Tisler, P.: Coastal winds and
low-level jets: Simulations for sea gulfs, Q. J. Roy. Meteor. Soc., 131, 625–637, https://doi.org/10.1256/QJ.03.177, 2005. a
Sayde, C., Thomas, C. K., Wagner, J., and Selker, J.: High-resolution wind speed measurements using actively heated fiber optics, Geophys. Res.
Lett., 42, 10064–10073, https://doi.org/10.1002/2015GL066729, 2015. a
Schaller, C., Göckede, M., and Foken, T.: Flux calculation of short turbulent events – comparison of three methods, Atmos. Meas. Tech., 10, 869–880, https://doi.org/10.5194/amt-10-869-2017, 2017. a, b
Schilperoort, B., Coenders-Gerrits, M., Luxemburg, W., Jiménez Rodríguez, C., Cisneros Vaca, C., and Savenije, H.: Technical note: Using distributed temperature sensing for Bowen ratio evaporation measurements, Hydrol. Earth Syst. Sci., 22, 819–830, https://doi.org/10.5194/hess-22-819-2018, 2018. a
Selker, J. S., Thévenaz, L., Huwald, H., Mallet, A., Luxemburg, W., Van De Giesen, N., Stejskal, M., Zeman, J., Westhoff, M., and Parlange, M. B.: Distributed fiber-optic temperature sensing for hydrologic systems, Water Resour. Res., 41, W12202, https://doi.org/10.1029/2006WR005326, 2006. a, b
Stull, R. B.: An Introduction to Boundary Layer Meteorology, vol. 13 of Atmospheric and Oceanographic Sciences Library, Springer Netherlands,
Dordrecht, ISBN 90-277-2768-6, 1988. a
Thomas, C. K., Kennedy, A. M., Selker, J. S., Moretti, A., Schroth, M. H., Smoot, A. R., Tufillaro, N. B., Zeeman, M. J., Thomas, C. K., Kennedy, A. M., Moretti, A., Smoot, A. R., Tufillaro, N. B., Zeeman, M. J., Selker, J. S., and Schroth, M. H.: High-Resolution Fibre-Optic Temperature Sensing: A New Tool to Study the Two-Dimensional Structure of Atmospheric Surface-Layer Flow, Bound.-Lay. Meteorol., 142, 177–192, https://doi.org/10.1007/S10546-011-9672-7, 2011.
a, b
Torrence, C. and Compo, G. P.: A Practical Guide to Wavelet Analysis, B. Am. Meteorol. Soc., 79, 61–78, https://doi.org/10.1175/1520-0477(1998)079<0061:APGTWA>2.0.CO;2, 1998. a, b, c, d
Tucker, S. C., Senff, C. J., Weickmann, A. M., Brewer, W. A., Banta, R. M., Sandberg, S. P., Law, D. C., and Hardesty, R. M.: Doppler lidar estimation of mixing height using turbulence, shear, and aerosol profiles, J. Atmos. Ocean. Tech., 26, 673–688, https://doi.org/10.1175/2008JTECHA1157.1, 2009. a
Tyler, S. W., Selker, J. S., Hausner, M. B., Hatch, C. E., Torgersen, T., Thodal, C. E., and Schladow, S. G.: Environmental temperature sensing using
Raman spectra DTS fiber-optic methods, Water Resour. Res., 46, W00D23,
https://doi.org/10.1029/2008WR007052, 2009. a
Venkatram, A.: An examination of methods to estimate the height of the coastal internal boundary layer, Bound.-Lay. Meteorol., 36, 149–156,
https://doi.org/10.1007/BF00117465, 1986. a
Vesala, T., Järvi, L., Launiainen, S., Sogachev, A., Rannik, Ũ.,
Mammarella, I., Siivola, E., Keronen, P., Rinne, J., Riikonen, A., and
Nikinmaa, E.: Surface-atmosphere interactions over complex urban terrain in
Helsinki, Finland, Tellus B, 60, 188–199,
https://doi.org/10.1111/j.1600-0889.2007.00312.x, 2008. a
Ward, H. C.: Scintillometry in urban and complex environments: a review, Meas. Sci. Technol., 28, 064005, https://doi.org/10.1088/1361-6501/aa5e85, 2017. a
Wilson, J. D.: Monin-Obukhov functions for standard deviations of velocity, Bound.-Lay. Meteorol., 129, 353–369, https://doi.org/10.1007/s10546-008-9319-5, 2008. a
Zeeman, M. J., Selker, J. S., and Thomas, C. K.: Near-Surface Motion in the
Nocturnal, Stable Boundary Layer Observed with Fibre-Optic Distributed
Temperature Sensing, Bound.-Lay. Meteorol., 154, 189–205,
https://doi.org/10.1007/S10546-014-9972-9, 2015. a
Short summary
To study the complex structure of the lowest tens of metres of atmosphere in urban areas, measurement methods with great spatial and temporal coverage are needed. In our study, we analyse measurements with a promising and relatively new method, distributed temperature sensing, capable of providing detailed information on the near-surface atmosphere. We present multiple ways to utilise these kinds of measurements, as well as important considerations for planning new studies using the method.
To study the complex structure of the lowest tens of metres of atmosphere in urban areas,...