Articles | Volume 16, issue 7
Atmos. Chem. Phys., 16, 4743–4756, 2016
https://doi.org/10.5194/acp-16-4743-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Atmos. Chem. Phys., 16, 4743–4756, 2016
https://doi.org/10.5194/acp-16-4743-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article 15 Apr 2016
Research article | 15 Apr 2016
Microwave signatures of ice hydrometeors from ground-based observations above Summit, Greenland
Claire Pettersen et al.
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Heather Guy, Ian M. Brooks, Ken S. Carslaw, Benjamin J. Murray, Von P. Walden, Matthew D. Shupe, Claire Pettersen, David D. Turner, Christopher J. Cox, William D. Neff, Ralf Bennartz, and Ryan R. Neely III
Atmos. Chem. Phys., 21, 15351–15374, https://doi.org/10.5194/acp-21-15351-2021, https://doi.org/10.5194/acp-21-15351-2021, 2021
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We present the first full year of surface aerosol number concentration measurements from the central Greenland Ice Sheet. Aerosol concentrations here have a distinct seasonal cycle from those at lower-altitude Arctic sites, which is driven by large-scale atmospheric circulation. Our results can be used to help understand the role aerosols might play in Greenland surface melt through the modification of cloud properties. This is crucial in a rapidly changing region where observations are sparse.
Elin A. McIlhattan, Claire Pettersen, Norman B. Wood, and Tristan S. L'Ecuyer
The Cryosphere, 14, 4379–4404, https://doi.org/10.5194/tc-14-4379-2020, https://doi.org/10.5194/tc-14-4379-2020, 2020
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Snowfall builds the mass of the Greenland Ice Sheet (GrIS) and reduces melt by brightening the surface. We present satellite observations of GrIS snowfall events divided into two regimes: those coincident with ice clouds and those coincident with mixed-phase clouds. Snowfall from ice clouds plays the dominant role in building the GrIS, producing ~ 80 % of total accumulation. The two regimes have similar snowfall frequency in summer, brightening the surface when solar insolation is at its peak.
Ralf Bennartz, Frank Fell, Claire Pettersen, Matthew D. Shupe, and Dirk Schuettemeyer
Atmos. Chem. Phys., 19, 8101–8121, https://doi.org/10.5194/acp-19-8101-2019, https://doi.org/10.5194/acp-19-8101-2019, 2019
Short summary
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The Greenland Ice Sheet (GrIS) is rapidly melting. Snowfall is the only source of ice mass over the GrIS. We use satellite observations to assess how much snow on average falls over the GrIS and what the annual cycle and spatial distribution of snowfall is. We find the annual mean snowfall over the GrIS inferred from CloudSat to be 34 ± 7.5 cm yr−1 liquid equivalent.
Claire Pettersen, Ralf Bennartz, Aronne J. Merrelli, Matthew D. Shupe, David D. Turner, and Von P. Walden
Atmos. Chem. Phys., 18, 4715–4735, https://doi.org/10.5194/acp-18-4715-2018, https://doi.org/10.5194/acp-18-4715-2018, 2018
Short summary
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A novel method for classifying Arctic precipitation using ground based remote sensors is presented. The classification reveals two distinct, primary regimes of precipitation over the central Greenland Ice Sheet: snowfall coupled to deep, fully glaciated ice clouds or to shallow, mixed-phase clouds. The ice clouds are associated with low-pressure storm systems from the southeast, while the mixed-phase clouds slowly propagate from the southwest along a quiescent flow.
Heather Guy, Ian M. Brooks, Ken S. Carslaw, Benjamin J. Murray, Von P. Walden, Matthew D. Shupe, Claire Pettersen, David D. Turner, Christopher J. Cox, William D. Neff, Ralf Bennartz, and Ryan R. Neely III
Atmos. Chem. Phys., 21, 15351–15374, https://doi.org/10.5194/acp-21-15351-2021, https://doi.org/10.5194/acp-21-15351-2021, 2021
Short summary
Short summary
We present the first full year of surface aerosol number concentration measurements from the central Greenland Ice Sheet. Aerosol concentrations here have a distinct seasonal cycle from those at lower-altitude Arctic sites, which is driven by large-scale atmospheric circulation. Our results can be used to help understand the role aerosols might play in Greenland surface melt through the modification of cloud properties. This is crucial in a rapidly changing region where observations are sparse.
Océane Hames, Mahdi Jafari, David N. Wagner, Ian Raphael, David Clemens-Sewall, Chris Polashenski, Matthew D. Shupe, Martin Schneebeli, and Michael Lehning
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-254, https://doi.org/10.5194/gmd-2021-254, 2021
Preprint under review for GMD
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This paper presents an Eulerian-Lagrangian snow transport model implemented in the fluid dynamics software OpenFOAM, which we call snowBedFoam 1.0. We apply this model to reproduce snow deposition on a piece of ridged Arctic sea ice, which was produced during the MOSAiC expedition through scan measurements. The model appears to successfully reproduce the enhanced snow accumulation and deposition patterns, although some quantitative uncertainties were shown.
Thomas E. Taylor, Christopher W. O'Dell, David Crisp, Akhiko Kuze, Hannakaisa Lindqvist, Paul O. Wennberg, Abhishek Chatterjee, Michael Gunson, Annmarie Eldering, Brendan Fisher, Matthäus Kiel, Robert R. Nelson, Aronne Merrelli, Greg Osterman, Frédéric Chevallier, Paul I. Palmer, Liang Feng, Nicholas M. Deutscher, Manvendra K. Dubey, Dietrich G. Feist, Omaira E. Garcia, David Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Cheng Liu, Martine De Mazière, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Coleen M. Roehl, Matthias Schneider, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, and Debra Wunch
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2021-247, https://doi.org/10.5194/essd-2021-247, 2021
Revised manuscript accepted for ESSD
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We provide an analysis of an eleven year record of atmospheric carbon dioxide (CO2) concentrations derived using an optimal estimation retrieval algorithm on measurements made by the GOSAT satellite . The new product (version 9) shows improvement over the previous version (v7.3) as evaluated against independent estimates of CO2 from ground-based sensors and atmospheric inversion systems. We also compare the new GOSAT CO2 values to collocated estimates from NASA's Orbiting Carbon Observatory-2.
Raghavendra Krishnamurthy, Rob K. Newsom, Larry K. Berg, Heng Xiao, Po-Lun Ma, and David D. Turner
Atmos. Meas. Tech., 14, 4403–4424, https://doi.org/10.5194/amt-14-4403-2021, https://doi.org/10.5194/amt-14-4403-2021, 2021
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Planetary boundary layer (PBL) height is a critical parameter in atmospheric models. Continuous PBL height measurements from remote sensing measurements are important to understand various boundary layer mechanisms, especially during daytime and evening transition periods. Due to several limitations in existing methodologies to detect PBL height from a Doppler lidar, in this study, a machine learning (ML) approach is tested. The ML model is observed to improve the accuracy by over 50 %.
Michael Gallagher, Matthew Shupe, Hélène Chepfer, and Tristan L'Ecuyer
The Cryosphere Discuss., https://doi.org/10.5194/tc-2021-150, https://doi.org/10.5194/tc-2021-150, 2021
Revised manuscript accepted for TC
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By using direct observations of snowfall and mass changes, the variability of daily snowfall mass input to the Greenland ice sheet is quantified for the first time. With new methods we conclude that cyclones west of Greenland in summer contribute the most snowfall, with 1.66 Gt per occurrence. These cyclones are contextualized in the broader Greenland climate and snowfall is validated against mass changes to verify the results. Snowfall and mass change observations are shown to agree well.
David D. Turner and Ulrich Löhnert
Atmos. Meas. Tech., 14, 3033–3048, https://doi.org/10.5194/amt-14-3033-2021, https://doi.org/10.5194/amt-14-3033-2021, 2021
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Temperature and humidity profiles in the lowest couple of kilometers near the surface are very important for many applications. Passive spectral radiometers are commercially available, and observations from these instruments have been used to get these profiles. However, new active lidar systems are able to measure partial profiles of water vapor. This paper investigates how the derived profiles of water vapor and temperature are improved when the active and passive observations are combined.
David N. Wagner, Matthew D. Shupe, Ola G. Persson, Taneil Uttal, Markus M. Frey, Amélie Kirchgaessner, Martin Schneebeli, Matthias Jaggi, Amy R. Macfarlane, Polona Itkin, Stefanie Arndt, Stefan Hendricks, Daniela Krampe, Robert Ricker, Julia Regnery, Nikolai Kolabutin, Egor Shimanshuck, Marc Oggier, Ian Raphael, and Michael Lehning
The Cryosphere Discuss., https://doi.org/10.5194/tc-2021-126, https://doi.org/10.5194/tc-2021-126, 2021
Revised manuscript under review for TC
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Based on measurements of the snow cover over sea ice and atmospheric measurements, we estimate snowfall and snow accumulation for the MOSAiC ice floe, between November 2019 and May 2020. For this period, we estimate 98–114 mm of precipitation. We suggest that about 34 mm of snow-water equivalent has accumulated until the end of April 2020 and that at least 50 % of the precipitated snow has been eroded or sublimated. Further, we suggest explanations for potential snowfall overestimation.
Steven T. Massie, Heather Cronk, Aronne Merrelli, Christopher O'Dell, K. Sebastian Schmidt, Hong Chen, and David Baker
Atmos. Meas. Tech., 14, 1475–1499, https://doi.org/10.5194/amt-14-1475-2021, https://doi.org/10.5194/amt-14-1475-2021, 2021
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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.
Jessie M. Creamean, Gijs de Boer, Hagen Telg, Fan Mei, Darielle Dexheimer, Matthew D. Shupe, Amy Solomon, and Allison McComiskey
Atmos. Chem. Phys., 21, 1737–1757, https://doi.org/10.5194/acp-21-1737-2021, https://doi.org/10.5194/acp-21-1737-2021, 2021
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Arctic clouds play a role in modulating sea ice extent. Importantly, aerosols facilitate cloud formation, and thus it is crucial to understand the interactions between aerosols and clouds. Vertical measurements of aerosols and clouds are needed to tackle this issue. We present results from balloon-borne measurements of aerosols and clouds over the course of 2 years in northern Alaska. These data shed light onto the vertical distributions of aerosols relative to clouds spanning multiple seasons.
Irina V. Djalalova, David D. Turner, Laura Bianco, James M. Wilczak, James Duncan, Bianca Adler, and Daniel Gottas
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-9, https://doi.org/10.5194/amt-2021-9, 2021
Revised manuscript under review for AMT
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In this paper we show the usefulness of observational data in the radiative transfer model to retrieve the reliable atmospheric temperature profiles. In particular, the additional data from radio acoustic sounding systems (RASS) could improve the temperature in terms of bias and RMSE in comparison to the radiosonde temperature profiles not only in the 200–2000 m atmospheric layer above the ground where RASS data available, but in the deep 0–5000 m atmosphere stratum.
Robert R. Nelson, Annmarie Eldering, David Crisp, Aronne J. Merrelli, and Christopher W. O'Dell
Atmos. Meas. Tech., 13, 6889–6899, https://doi.org/10.5194/amt-13-6889-2020, https://doi.org/10.5194/amt-13-6889-2020, 2020
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Measurements of surface wind speed over oceans are scientifically useful. Here we show that the Orbiting Carbon Observatory-2 (OCO-2), originally designed to measure carbon dioxide using reflected sunlight, can also accurately and precisely measure wind speed. OCO-2's high spatial resolution means that it can observe close to coastlines and therefore be used to study coastal wind processes and inform related economic sectors.
Elin A. McIlhattan, Claire Pettersen, Norman B. Wood, and Tristan S. L'Ecuyer
The Cryosphere, 14, 4379–4404, https://doi.org/10.5194/tc-14-4379-2020, https://doi.org/10.5194/tc-14-4379-2020, 2020
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Snowfall builds the mass of the Greenland Ice Sheet (GrIS) and reduces melt by brightening the surface. We present satellite observations of GrIS snowfall events divided into two regimes: those coincident with ice clouds and those coincident with mixed-phase clouds. Snowfall from ice clouds plays the dominant role in building the GrIS, producing ~ 80 % of total accumulation. The two regimes have similar snowfall frequency in summer, brightening the surface when solar insolation is at its peak.
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.
Anne Sophie Daloz, Marian Mateling, Tristan L'Ecuyer, Mark Kulie, Norm B. Wood, Mikael Durand, Melissa Wrzesien, Camilla W. Stjern, and Ashok P. Dimri
The Cryosphere, 14, 3195–3207, https://doi.org/10.5194/tc-14-3195-2020, https://doi.org/10.5194/tc-14-3195-2020, 2020
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The total of snow that falls globally is a critical factor governing freshwater availability. To better understand how this resource is impacted by climate change, we need to know how reliable the current observational datasets for snow are. Here, we compare five datasets looking at the snow falling over the mountains versus the other continents. We show that there is a large consensus when looking at fractional contributions but strong dissimilarities when comparing magnitudes.
Rosa Gierens, Stefan Kneifel, Matthew D. Shupe, Kerstin Ebell, Marion Maturilli, and Ulrich Löhnert
Atmos. Chem. Phys., 20, 3459–3481, https://doi.org/10.5194/acp-20-3459-2020, https://doi.org/10.5194/acp-20-3459-2020, 2020
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Multiyear statistics of persistent low-level mixed-phase clouds observed at an Arctic fjord environment in Svalbard are presented. The effects the local boundary layer (i.e. the fjords' wind climate and surface coupling), regional wind direction, and seasonality have on the cloud occurrence and properties are evaluated using a synergy of ground-based remote sensing methods and auxiliary data. The phenomena considered were found to modify the amount of liquid and ice in the studied clouds.
Laura Bianco, Irina V. Djalalova, James M. Wilczak, Joseph B. Olson, Jaymes S. Kenyon, Aditya Choukulkar, Larry K. Berg, Harindra J. S. Fernando, Eric P. Grimit, Raghavendra Krishnamurthy, Julie K. Lundquist, Paytsar Muradyan, Mikhail Pekour, Yelena Pichugina, Mark T. Stoelinga, and David D. Turner
Geosci. Model Dev., 12, 4803–4821, https://doi.org/10.5194/gmd-12-4803-2019, https://doi.org/10.5194/gmd-12-4803-2019, 2019
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During the second Wind Forecast Improvement Project, improvements to the parameterizations were applied to the High Resolution Rapid Refresh model and its nested version. The impacts of the new parameterizations on the forecast of 80 m wind speeds and power are assessed, using sodars and profiling lidars observations for comparison. Improvements are evaluated as a function of the model’s initialization time, forecast horizon, time of the day, season, site elevation, and meteorological phenomena.
Gijs de Boer, Darielle Dexheimer, Fan Mei, John Hubbe, Casey Longbottom, Peter J. Carroll, Monty Apple, Lexie Goldberger, David Oaks, Justin Lapierre, Michael Crume, Nathan Bernard, Matthew D. Shupe, Amy Solomon, Janet Intrieri, Dale Lawrence, Abhiram Doddi, Donna J. Holdridge, Michael Hubbell, Mark D. Ivey, and Beat Schmid
Earth Syst. Sci. Data, 11, 1349–1362, https://doi.org/10.5194/essd-11-1349-2019, https://doi.org/10.5194/essd-11-1349-2019, 2019
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This paper provides a summary of observations collected at Oliktok Point, Alaska, as part of the Profiling at Oliktok Point to Enhance YOPP Experiments (POPEYE) campaign. The Year of Polar Prediction (YOPP) is a multi-year concentrated effort to improve forecasting capabilities at high latitudes across a variety of timescales. POPEYE observations include atmospheric data collected using unmanned aircraft, tethered balloons, and radiosondes, made in parallel with routine measurements at the site.
Ralf Bennartz, Frank Fell, Claire Pettersen, Matthew D. Shupe, and Dirk Schuettemeyer
Atmos. Chem. Phys., 19, 8101–8121, https://doi.org/10.5194/acp-19-8101-2019, https://doi.org/10.5194/acp-19-8101-2019, 2019
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The Greenland Ice Sheet (GrIS) is rapidly melting. Snowfall is the only source of ice mass over the GrIS. We use satellite observations to assess how much snow on average falls over the GrIS and what the annual cycle and spatial distribution of snowfall is. We find the annual mean snowfall over the GrIS inferred from CloudSat to be 34 ± 7.5 cm yr−1 liquid equivalent.
Christopher J. Cox, David C. Noone, Max Berkelhammer, Matthew D. Shupe, William D. Neff, Nathaniel B. Miller, Von P. Walden, and Konrad Steffen
Atmos. Chem. Phys., 19, 7467–7485, https://doi.org/10.5194/acp-19-7467-2019, https://doi.org/10.5194/acp-19-7467-2019, 2019
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Fogs are frequently reported by observers on the Greenland Ice Sheet. Fogs play a role in the hydrological and energetic balances of the ice sheet surface, but as yet the properties of Greenland fogs are not well known. We observed fogs in all months from Summit Station for 2 years and report their properties. Annually, fogs impart a slight warming to the surface and a case study suggests that they are particularly influential by providing insulation during the coldest part of the day in summer.
Christopher W. O'Dell, Annmarie Eldering, Paul O. Wennberg, David Crisp, Michael R. Gunson, Brendan Fisher, Christian Frankenberg, Matthäus Kiel, Hannakaisa Lindqvist, Lukas Mandrake, Aronne Merrelli, Vijay Natraj, Robert R. Nelson, Gregory B. Osterman, Vivienne H. Payne, Thomas E. Taylor, Debra Wunch, Brian J. Drouin, Fabiano Oyafuso, Albert Chang, James McDuffie, Michael Smyth, David F. Baker, Sourish Basu, Frédéric Chevallier, Sean M. R. Crowell, Liang Feng, Paul I. Palmer, Mavendra Dubey, Omaira E. García, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Isamu Morino, Justus Notholt, Hirofumi Ohyama, Christof Petri, Coleen M. Roehl, Mahesh K. Sha, Kimberly Strong, Ralf Sussmann, Yao Te, Osamu Uchino, and Voltaire A. Velazco
Atmos. Meas. Tech., 11, 6539–6576, https://doi.org/10.5194/amt-11-6539-2018, https://doi.org/10.5194/amt-11-6539-2018, 2018
Amy Solomon, Gijs de Boer, Jessie M. Creamean, Allison McComiskey, Matthew D. Shupe, Maximilian Maahn, and Christopher Cox
Atmos. Chem. Phys., 18, 17047–17059, https://doi.org/10.5194/acp-18-17047-2018, https://doi.org/10.5194/acp-18-17047-2018, 2018
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The results of this study indicate that perturbations in ice nucleating particles (INPs) dominate over cloud condensation nuclei (CCN) perturbations in Arctic mixed-phase stratocumulus; i.e., an equivalent fractional decrease in CCN and INPs results in an increase in the cloud-top longwave cooling rate, even though the droplet effective radius increases and the cloud emissivity decreases. In addition, cloud-processing causes layering of aerosols with increased concentrations of CCN at cloud top.
Matthew S. Norgren, Gijs de Boer, and Matthew D. Shupe
Atmos. Chem. Phys., 18, 13345–13361, https://doi.org/10.5194/acp-18-13345-2018, https://doi.org/10.5194/acp-18-13345-2018, 2018
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Arctic mixed-phase clouds are a critical component of the Arctic climate system because of their ability to influence the surface radiation budget. The radiative impact of an individual cloud is closely linked to the ability of the cloud to convert liquid drops to ice. In this paper, we show through an observational record that clouds present in polluted atmospheric conditions have lower amounts of ice than similar clouds found in clean conditions.
Chellappan Seethala, Jan Fokke Meirink, Ákos Horváth, Ralf Bennartz, and Rob Roebeling
Atmos. Chem. Phys., 18, 13283–13304, https://doi.org/10.5194/acp-18-13283-2018, https://doi.org/10.5194/acp-18-13283-2018, 2018
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We compared the microphysical properties of South Atlantic stratocumulus (Sc) from three different satellite instruments (SEVIRI, TMI, MODIS). The liquid water path (LWP) and its diurnal cycle from the three datasets agreed very well in overcast, smoke-free scenes. LWP showed a decrease from an early morning peak to a late afternoon minimum, after which it increased until morning. The presence of smoke aloft Sc, however, negatively biased the LWP retrieved by the visible/near-infrared technique.
Claire Pettersen, Ralf Bennartz, Aronne J. Merrelli, Matthew D. Shupe, David D. Turner, and Von P. Walden
Atmos. Chem. Phys., 18, 4715–4735, https://doi.org/10.5194/acp-18-4715-2018, https://doi.org/10.5194/acp-18-4715-2018, 2018
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A novel method for classifying Arctic precipitation using ground based remote sensors is presented. The classification reveals two distinct, primary regimes of precipitation over the central Greenland Ice Sheet: snowfall coupled to deep, fully glaciated ice clouds or to shallow, mixed-phase clouds. The ice clouds are associated with low-pressure storm systems from the southeast, while the mixed-phase clouds slowly propagate from the southwest along a quiescent flow.
Robert A. Stillwell, Ryan R. Neely III, Jeffrey P. Thayer, Matthew D. Shupe, and David D. Turner
Atmos. Meas. Tech., 11, 835–859, https://doi.org/10.5194/amt-11-835-2018, https://doi.org/10.5194/amt-11-835-2018, 2018
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This work focuses on making unambiguous measurements of Arctic cloud phase and assessing those measurements within the context of cloud radiative effects. It is found that effects related to lidar data recording systems can cause retrieval ambiguities that alter the interpretation of cloud phase in as much as 30 % of the available data. This misinterpretation of cloud-phase data can cause a misinterpretation of the effect of cloud phase on the surface radiation budget by as much as 10 to 30 %.
Ralf Bennartz and John Rausch
Atmos. Chem. Phys., 17, 9815–9836, https://doi.org/10.5194/acp-17-9815-2017, https://doi.org/10.5194/acp-17-9815-2017, 2017
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Cloud droplet number concentration is linked to air pollution levels via indirect aerosol effects. The climatological results presented here provide constraints on cloud droplet number concentration globally, thereby helping to evaluate global climate models and study the impact of pollution regionally and globally.
Yann Blanchard, Alain Royer, Norman T. O'Neill, David D. Turner, and Edwin W. Eloranta
Atmos. Meas. Tech., 10, 2129–2147, https://doi.org/10.5194/amt-10-2129-2017, https://doi.org/10.5194/amt-10-2129-2017, 2017
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Multiband thermal measurements of zenith sky radiance were used in a retrieval algorithm, to estimate cloud optical depth and effective particle diameter of thin ice clouds in the Canadian High Arctic. The retrieval technique was validated using a synergy lidar and radar data. Inversions were performed across three polar winters and results showed a significant correlation (R2 = 0.95) for cloud optical depth retrievals and an overall accuracy of 83 % for the classification of thin ice clouds.
John Rausch, Kerry Meyer, Ralf Bennartz, and Steven Platnick
Atmos. Meas. Tech., 10, 2105–2116, https://doi.org/10.5194/amt-10-2105-2017, https://doi.org/10.5194/amt-10-2105-2017, 2017
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This paper documents the observed differences in the aggregated (Level-3) cloud droplet effective radius and droplet number concentration estimates inferred from the Aqua–MODIS cloud product collections 5.1 and 6 for warm oceanic cloud scenes over the year 2008. We note significant differences in effective radius and droplet concentration between the two products and discuss the algorithmic and calibration changes which may contribute to observed results.
Yinghui Liu, Matthew D. Shupe, Zhien Wang, and Gerald Mace
Atmos. Chem. Phys., 17, 5973–5989, https://doi.org/10.5194/acp-17-5973-2017, https://doi.org/10.5194/acp-17-5973-2017, 2017
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Detailed and accurate vertical distributions of cloud properties are essential to accurately calculate the surface radiative flux and to depict the mean climate state, and such information is more desirable in the Arctic due to its recent rapid changes and the challenging observation conditions. This study presents a feasible way to provide such information by blending cloud observations from surface and space-based instruments with the understanding of their respective strength and limitations.
Ralf Bennartz, Heidrun Höschen, Bruno Picard, Marc Schröder, Martin Stengel, Oliver Sus, Bojan Bojkov, Stefano Casadio, Hannes Diedrich, Salomon Eliasson, Frank Fell, Jürgen Fischer, Rainer Hollmann, Rene Preusker, and Ulrika Willén
Atmos. Meas. Tech., 10, 1387–1402, https://doi.org/10.5194/amt-10-1387-2017, https://doi.org/10.5194/amt-10-1387-2017, 2017
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The microwave radiometers (MWR) on board ERS-1, ERS-2, and Envisat provide a continuous time series of brightness temperature observations between 1991 and 2012. Here we report on a new total column water vapour (TCWV) and wet tropospheric correction (WTC) dataset that builds on this time series. The dataset is publicly available under doi:10.5676/DWD_EMIR/V001.
Nathaniel B. Miller, Matthew D. Shupe, Christopher J. Cox, David Noone, P. Ola G. Persson, and Konrad Steffen
The Cryosphere, 11, 497–516, https://doi.org/10.5194/tc-11-497-2017, https://doi.org/10.5194/tc-11-497-2017, 2017
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A comprehensive observational dataset is assembled to investigate atmosphere–Greenland ice sheet interactions and characterize surface temperature variability. The amount the surface temperature warms, due to increases in cloud presence and/or elevated sun angle, varies throughout the annual cycle and is modulated by the responses of latent, sensible and ground heat fluxes. This observationally based study provides process-based relationships, which are useful for evaluation of climate models.
Robert A. Stillwell, Ryan R. Neely III, Jeffrey P. Thayer, Matthew D. Shupe, and Michael O'Neill
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2016-303, https://doi.org/10.5194/amt-2016-303, 2016
Revised manuscript not accepted
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This work explores the observation of Arctic mixed phase clouds by lidar and the consequences of mishandling lidar signals linking the signals to their geophysical interpretation. It concludes 3 points: 1) cloud phase identification is not only linked to cloud phase but other cloud properties, 2) having more than two polarization signals can be used to quality control data not possible with only two signals, and 3) phase retrievals with more than two polarizations enhance retrieval flexibility.
Andrew M. Dzambo, David D. Turner, and Eli J. Mlawer
Atmos. Meas. Tech., 9, 1613–1626, https://doi.org/10.5194/amt-9-1613-2016, https://doi.org/10.5194/amt-9-1613-2016, 2016
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Radiosondes are used to characterize the humidity in the middle and upper troposphere, but suffer from a solar radiation induced dry bias. This work investigates the accuracy of two published correction algorithms using comparisons with other instruments.
T. M. Gray and R. Bennartz
Atmos. Meas. Tech., 8, 5089–5097, https://doi.org/10.5194/amt-8-5089-2015, https://doi.org/10.5194/amt-8-5089-2015, 2015
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Volcanic ash poses a serious threat to aircraft traffic. A simple neural-network based technique was developed to detect volcanic ash from space using satellite infrared observations. A validation study shows promising results for several individual case studies. Issues remain near the edge of the satellite's field of view as well as in situations where ash is mixed with meteorological clouds.
A. Lattanzio, F. Fell, R. Bennartz, I. F. Trigo, and J. Schulz
Atmos. Meas. Tech., 8, 4561–4571, https://doi.org/10.5194/amt-8-4561-2015, https://doi.org/10.5194/amt-8-4561-2015, 2015
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EUMETSAT has generated a surface albedo data set climate data record, spanning over more than 2 decades, from measurements acquired by Meteosat First Generation satellites. EUMETSAT coordinated a study for the validation of such a data record. In the validation report, the full set of results, including comparison with in situ measurements and satellites, was presented. A method of increasing the quality of the data set, removing cloud-contaminated pixels, is presented.
A. Solomon, G. Feingold, and M. D. Shupe
Atmos. Chem. Phys., 15, 10631–10643, https://doi.org/10.5194/acp-15-10631-2015, https://doi.org/10.5194/acp-15-10631-2015, 2015
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The maintenance of cloud ice production in Arctic mixed-phase stratocumulus is investigated in large eddy simulations that include a prognostic ice nuclei (IN) formulation and a diurnal cycle. It is demonstrated that IN recycling through subcloud sublimation prolongs ice production. Competing feedbacks between dynamical mixing and recycling are found to slow the rate of ice lost. The results of this study have important implications for the maintenance of phase partitioning in Arctic clouds.
A. Merrelli, R. Bennartz, C. W. O'Dell, and T. E. Taylor
Atmos. Meas. Tech., 8, 1641–1656, https://doi.org/10.5194/amt-8-1641-2015, https://doi.org/10.5194/amt-8-1641-2015, 2015
G. Sotiropoulou, J. Sedlar, M. Tjernström, M. D. Shupe, I. M. Brooks, and P. O. G. Persson
Atmos. Chem. Phys., 14, 12573–12592, https://doi.org/10.5194/acp-14-12573-2014, https://doi.org/10.5194/acp-14-12573-2014, 2014
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During ASCOS, clouds are more frequently decoupled from the surface than coupled to it; when coupling occurs it is primary driven by the cloud. Decoupled clouds have a bimodal structure; they are either weakly or strongly decoupled from the surface; the enhancement of the decoupling is possibly due to sublimation of precipitation. Stable clouds (no cloud-driven mixing) are also observed; those are optically thin, often single-phase liquid, with no or negligible precipitation (e.g. fog).
J. M. Intrieri, G. de Boer, M. D. Shupe, J. R. Spackman, J. Wang, P. J. Neiman, G. A. Wick, T. F. Hock, and R. E. Hood
Atmos. Meas. Tech., 7, 3917–3926, https://doi.org/10.5194/amt-7-3917-2014, https://doi.org/10.5194/amt-7-3917-2014, 2014
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In winter 2011, the Global Hawk unmanned aircraft system (UAS) was deployed over the Arctic to evaluate a UAS dropsonde system at high latitudes. Dropsondes deployed from the Global Hawk successfully obtained high-resolution profiles of temperature, pressure, humidity, and wind speed and direction information between the stratosphere and surface. During the 25-hour polar flight, the Global Hawk released 35 sondes between the North Slope of Alaska and 85° N latitude.
U. Hamann, A. Walther, B. Baum, R. Bennartz, L. Bugliaro, M. Derrien, P. N. Francis, A. Heidinger, S. Joro, A. Kniffka, H. Le Gléau, M. Lockhoff, H.-J. Lutz, J. F. Meirink, P. Minnis, R. Palikonda, R. Roebeling, A. Thoss, S. Platnick, P. Watts, and G. Wind
Atmos. Meas. Tech., 7, 2839–2867, https://doi.org/10.5194/amt-7-2839-2014, https://doi.org/10.5194/amt-7-2839-2014, 2014
J. Sedlar and M. D. Shupe
Atmos. Chem. Phys., 14, 3461–3478, https://doi.org/10.5194/acp-14-3461-2014, https://doi.org/10.5194/acp-14-3461-2014, 2014
A. Kniffka, M. Stengel, M. Lockhoff, R. Bennartz, and R. Hollmann
Atmos. Meas. Tech., 7, 887–905, https://doi.org/10.5194/amt-7-887-2014, https://doi.org/10.5194/amt-7-887-2014, 2014
M. Tjernström, C. Leck, C. E. Birch, J. W. Bottenheim, B. J. Brooks, I. M. Brooks, L. Bäcklin, R. Y.-W. Chang, G. de Leeuw, L. Di Liberto, S. de la Rosa, E. Granath, M. Graus, A. Hansel, J. Heintzenberg, A. Held, A. Hind, P. Johnston, J. Knulst, M. Martin, P. A. Matrai, T. Mauritsen, M. Müller, S. J. Norris, M. V. Orellana, D. A. Orsini, J. Paatero, P. O. G. Persson, Q. Gao, C. Rauschenberg, Z. Ristovski, J. Sedlar, M. D. Shupe, B. Sierau, A. Sirevaag, S. Sjogren, O. Stetzer, E. Swietlicki, M. Szczodrak, P. Vaattovaara, N. Wahlberg, M. Westberg, and C. R. Wheeler
Atmos. Chem. Phys., 14, 2823–2869, https://doi.org/10.5194/acp-14-2823-2014, https://doi.org/10.5194/acp-14-2823-2014, 2014
G. de Boer, M. D. Shupe, P. M. Caldwell, S. E. Bauer, O. Persson, J. S. Boyle, M. Kelley, S. A. Klein, and M. Tjernström
Atmos. Chem. Phys., 14, 427–445, https://doi.org/10.5194/acp-14-427-2014, https://doi.org/10.5194/acp-14-427-2014, 2014
M. D. Shupe, P. O. G. Persson, I. M. Brooks, M. Tjernström, J. Sedlar, T. Mauritsen, S. Sjogren, and C. Leck
Atmos. Chem. Phys., 13, 9379–9399, https://doi.org/10.5194/acp-13-9379-2013, https://doi.org/10.5194/acp-13-9379-2013, 2013
Related subject area
Subject: Radiation | Research Activity: Remote Sensing | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Ice and mixed-phase cloud statistics on the Antarctic Plateau
Photovoltaic power potential in West Africa using long-term satellite data
A semi-empirical potential energy surface and line list for H216O extending into the near-ultraviolet
Global distribution and 14-year changes in erythemal irradiance, UV atmospheric transmission, and total column ozone for2005–2018 estimated from OMI and EPIC observations
Biomass-burning-induced surface darkening and its impact on regional meteorology in eastern China
Air pollution slows down surface warming over the Tibetan Plateau
Estimation of hourly land surface heat fluxes over the Tibetan Plateau by the combined use of geostationary and polar-orbiting satellites
Estimations of global shortwave direct aerosol radiative effects above opaque water clouds using a combination of A-Train satellite sensors
Uncertainty of atmospheric microwave absorption model: impact on ground-based radiometer simulations and retrievals
Simulated and observed horizontal inhomogeneities of optical thickness of Arctic stratus
Net radiative effects of dust in the tropical North Atlantic based on integrated satellite observations and in situ measurements
Comparison of global observations and trends of total precipitable water derived from microwave radiometers and COSMIC radio occultation from 2006 to 2013
Characterizing energy budget variability at a Sahelian site: a test of NWP model behaviour
Scale dependence of cirrus horizontal heterogeneity effects on TOA measurements – Part I: MODIS brightness temperatures in the thermal infrared
Aerosol scattering effects on water vapor retrievals over the Los Angeles Basin
Directional, horizontal inhomogeneities of cloud optical thickness fields retrieved from ground-based and airbornespectral imaging
Airborne observations of far-infrared upwelling radiance in the Arctic
Retrieval of aerosol optical depth from surface solar radiation measurements using machine learning algorithms, non-linear regression and a radiative transfer-based look-up table
Shortwave direct radiative effects of above-cloud aerosols over global oceans derived from 8 years of CALIOP and MODIS observations
Retrieving high-resolution surface solar radiation with cloud parameters derived by combining MODIS and MTSAT data
Instantaneous longwave radiative impact of ozone: an application on IASI/MetOp observations
A method to retrieve super-thin cloud optical depth over ocean background with polarized sunlight
Airborne observations and simulations of three-dimensional radiative interactions between Arctic boundary layer clouds and ice floes
Deriving polarization properties of desert-reflected solar spectra with PARASOL data
Using IASI to simulate the total spectrum of outgoing long-wave radiances
Investigation of the "elevated heat pump" hypothesis of the Asian monsoon using satellite observations
Improved retrieval of direct and diffuse downwelling surface shortwave flux in cloudless atmosphere using dynamic estimates of aerosol content and type: application to the LSA-SAF project
Surface-sensible and latent heat fluxes over the Tibetan Plateau from ground measurements, reanalysis, and satellite data
Influence of local surface albedo variability and ice crystal shape on passive remote sensing of thin cirrus
Combining MODIS, AVHRR and in situ data for evapotranspiration estimation over heterogeneous landscape of the Tibetan Plateau
Modeling polarized solar radiation from the ocean–atmosphere system for CLARREO inter-calibration applications
HIRS channel 12 brightness temperature dataset and its correlations with major climate indices
Performance of the Line-By-Line Radiative Transfer Model (LBLRTM) for temperature, water vapor, and trace gas retrievals: recent updates evaluated with IASI case studies
Multi-satellite aerosol observations in the vicinity of clouds
CLARA-SAL: a global 28 yr timeseries of Earth's black-sky surface albedo
Quantitative comparison of the variability in observed and simulated shortwave reflectance
Regional radiative impact of volcanic aerosol from the 2009 eruption of Mt. Redoubt
Airborne hyperspectral observations of surface and cloud directional reflectivity using a commercial digital camera
Direct and semi-direct radiative forcing of smoke aerosols over clouds
Validity of satellite measurements used for the monitoring of UV radiation risk on health
Statistics of vertical backscatter profiles of cirrus clouds
Using surface remote sensors to derive radiative characteristics of Mixed-Phase Clouds: an example from M-PACE
Determination of land surface heat fluxes over heterogeneous landscape of the Tibetan Plateau by using the MODIS and in situ data
Cirrus cloud-temperature interactions in the tropical tropopause layer: a case study
Characteristics of water-vapour inversions observed over the Arctic by Atmospheric Infrared Sounder (AIRS) and radiosondes
Use of satellite erythemal UV products in analysing the global UV changes
Effects of absorbing aerosols in cloudy skies: a satellite study over the Atlantic Ocean
Spectrally-invariant behavior of zenith radiance around cloud edges simulated by radiative transfer
Assessment of the calibration performance of satellite visible channels using cloud targets: application to Meteosat-8/9 and MTSAT-1R
Downscaling of METEOSAT SEVIRI 0.6 and 0.8 μm channel radiances utilizing the high-resolution visible channel
William Cossich, Tiziano Maestri, Davide Magurno, Michele Martinazzo, Gianluca Di Natale, Luca Palchetti, Giovanni Bianchini, and Massimo Del Guasta
Atmos. Chem. Phys., 21, 13811–13833, https://doi.org/10.5194/acp-21-13811-2021, https://doi.org/10.5194/acp-21-13811-2021, 2021
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The presence of clouds over Concordia, in the Antarctic Plateau, is investigated. Results are obtained by applying a machine learning algorithm to measurements of the infrared radiation emitted by the atmosphere toward the surface. The clear-sky, ice cloud, and mixed-phase cloud occurrence at different timescales is studied. A comparison with satellite measurements highlights the ability of the algorithm to identify multiple cloud conditions and study their variability at different timescales.
Ina Neher, Susanne Crewell, Stefanie Meilinger, Uwe Pfeifroth, and Jörg Trentmann
Atmos. Chem. Phys., 20, 12871–12888, https://doi.org/10.5194/acp-20-12871-2020, https://doi.org/10.5194/acp-20-12871-2020, 2020
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Photovoltaic power is one current option to meet the rising energy demand with low environmental impact. Global horizontal irradiance (GHI) is the fuel for photovoltaic power installations and needs to be evaluated to plan and dimension power plants. In this study, 35 years of satellite-based GHI data are analyzed over West Africa to determine their impact on photovoltaic power generation. The major challenges for the development of a solar-based power system in West Africa are then outlined.
Eamon K. Conway, Iouli E. Gordon, Jonathan Tennyson, Oleg L. Polyansky, Sergei N. Yurchenko, and Kelly Chance
Atmos. Chem. Phys., 20, 10015–10027, https://doi.org/10.5194/acp-20-10015-2020, https://doi.org/10.5194/acp-20-10015-2020, 2020
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Water vapour has a complex spectrum and absorbs from the microwave to the near-UV where it dissociates. There is limited knowledge of the absorption features in the near-UV, and there is a large disagreement for the available models and experiments. We created a new ab initio model that is in good agreement with observation at 363 nm. At lower wavelengths, our calculations suggest that the latest experiments overestimate absorption. This has implications for trace gas retrievals in the near-UV.
Jay Herman, Alexander Cede, Liang Huang, Jerald Ziemke, Omar Torres, Nickolay Krotkov, Matthew Kowalewski, and Karin Blank
Atmos. Chem. Phys., 20, 8351–8380, https://doi.org/10.5194/acp-20-8351-2020, https://doi.org/10.5194/acp-20-8351-2020, 2020
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The amount of erythemal irradiance reaching the Earth's surface has been calculated from ozone, aerosol, and reflectivity data obtained from OMI and DSCOVR/EPIC satellite instruments showing areas with high levels of solar UV radiation. Changes in erythemal irradiance, cloud transmission, aerosol transmission, and ozone absorption have been estimated for 14 years 2005–2018 in units of percent per year for 191 locations, mostly large cities, and from EPIC for the entire illuminated Earth.
Rong Tang, Xin Huang, Derong Zhou, and Aijun Ding
Atmos. Chem. Phys., 20, 6177–6191, https://doi.org/10.5194/acp-20-6177-2020, https://doi.org/10.5194/acp-20-6177-2020, 2020
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Biomass-burning-induced large areas of dark char (i.e.
surface darkening) could influence the radiative energy balance. During the harvest season in eastern China, satellite retrieval shows that surface albedo was significantly decreased. Observational evidence of meteorological perturbations from the surface darkening is identified, which is further examined by model simulation. This work highlights the importance of burning-induced albedo change in weather forecast and regional climate.
Aolin Jia, Shunlin Liang, Dongdong Wang, Bo Jiang, and Xiaotong Zhang
Atmos. Chem. Phys., 20, 881–899, https://doi.org/10.5194/acp-20-881-2020, https://doi.org/10.5194/acp-20-881-2020, 2020
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The Tibetan Plateau (TP) plays a vital role in regional and global climate change due to its location and orography. After generating a long-term surface radiation (SR) dataset, we characterized the SR spatiotemporal variation along with temperature. Evidence from multiple data sources indicated that the TP dimming was primarily driven by increased aerosols from human activities, and the cooling effect of aerosol loading offsets TP surface warming, revealing the human impact on regional warming.
Lei Zhong, Yaoming Ma, Zeyong Hu, Yunfei Fu, Yuanyuan Hu, Xian Wang, Meilin Cheng, and Nan Ge
Atmos. Chem. Phys., 19, 5529–5541, https://doi.org/10.5194/acp-19-5529-2019, https://doi.org/10.5194/acp-19-5529-2019, 2019
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Fine-temporal-resolution turbulent heat fluxes at the plateau scale have significant importance for studying diurnal variation characteristics of atmospheric boundary and weather systems in the Tibetan Plateau (TP) and its surroundings. Time series of land surface heat fluxes with high temporal resolution over the entire TP were derived. The derived surface heat fluxes proved to be in good agreement with in situ measurements and were superior to GLDAS flux products.
Meloë S. Kacenelenbogen, Mark A. Vaughan, Jens Redemann, Stuart A. Young, Zhaoyan Liu, Yongxiang Hu, Ali H. Omar, Samuel LeBlanc, Yohei Shinozuka, John Livingston, Qin Zhang, and Kathleen A. Powell
Atmos. Chem. Phys., 19, 4933–4962, https://doi.org/10.5194/acp-19-4933-2019, https://doi.org/10.5194/acp-19-4933-2019, 2019
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Significant efforts are required to estimate the direct radiative effects of aerosols above clouds (DAREcloudy). We have used a combination of passive and active A-Train satellite sensors and derive mainly positive global and regional DAREcloudy values (e.g., global seasonal values between 0.13 and 0.26 W m-2). Despite differences in methods and sensors, the DAREcloudy values in this study are generally higher than previously reported. We discuss the primary reasons for these higher estimates.
Domenico Cimini, Philip W. Rosenkranz, Mikhail Y. Tretyakov, Maksim A. Koshelev, and Filomena Romano
Atmos. Chem. Phys., 18, 15231–15259, https://doi.org/10.5194/acp-18-15231-2018, https://doi.org/10.5194/acp-18-15231-2018, 2018
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The paper presents a general approach to quantify the uncertainty related to atmospheric absorption models. These models describe how the atmosphere interacts with radiation, and they have general implications for atmospheric sciences.
The presented approach contributes to a better understanding of the total uncertainty affecting atmospheric radiative properties, thus reducing the chances of systematic errors when observations are exploited for weather forecast or climate trend derivations.
Michael Schäfer, Katharina Loewe, André Ehrlich, Corinna Hoose, and Manfred Wendisch
Atmos. Chem. Phys., 18, 13115–13133, https://doi.org/10.5194/acp-18-13115-2018, https://doi.org/10.5194/acp-18-13115-2018, 2018
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Airborne observed horizontal fields of cloud optical thickness are compared with semi-idealized large eddy simulations of Arctic stratus. The comparison focuses on horizontal cloud inhomogeneities and directional features of the small-scale cloud structures. Using inhomogeneity parameters and autocorrelation analysis it is investigated, if the observed small-scale cloud inhomogeneities can be represented by the model. Forcings for cloud inhomogeneities are investigated in a sensitivity study.
Qianqian Song, Zhibo Zhang, Hongbin Yu, Seiji Kato, Ping Yang, Peter Colarco, Lorraine A. Remer, and Claire L. Ryder
Atmos. Chem. Phys., 18, 11303–11322, https://doi.org/10.5194/acp-18-11303-2018, https://doi.org/10.5194/acp-18-11303-2018, 2018
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Mineral dust is the most abundant atmospheric aerosol component in terms of dry mass. In this study, we integrate recent aircraft measurements of dust microphysical and optical properties with satellite retrievals of aerosol and radiative fluxes to quantify the dust direct radiative effects on the shortwave and longwave radiation at both the top of the atmosphere and the surface in the tropical North Atlantic during summer months.
Shu-Peng Ho, Liang Peng, Carl Mears, and Richard A. Anthes
Atmos. Chem. Phys., 18, 259–274, https://doi.org/10.5194/acp-18-259-2018, https://doi.org/10.5194/acp-18-259-2018, 2018
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In this study, we compare 7 years of atmospheric total precipitable water (TPW) derived from multiple microwave radiometers to collocated TPW estimates derived from COSMIC radio occultation under various atmospheric conditions over the oceans. Results show that these two TPW trends from independent observations are larger than previous estimates and are a strong indication of the positive water vapor–temperature feedback on a warming planet.
Anna Mackie, Paul I. Palmer, and Helen Brindley
Atmos. Chem. Phys., 17, 15095–15119, https://doi.org/10.5194/acp-17-15095-2017, https://doi.org/10.5194/acp-17-15095-2017, 2017
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We compare the balance of solar and thermal radiation at the surface and the top of the atmosphere from a forecasting model to observations at a site in Niamey, Niger, in the Sahel. To interpret the energy budgets we examine other factors, such as cloud properties, water vapour and aerosols, which we use to understand the differences between the observation and model. We find that some differences are linked to lack of ice in clouds, underestimated aerosol loading and surface temperatures.
Thomas Fauchez, Steven Platnick, Kerry Meyer, Céline Cornet, Frédéric Szczap, and Tamás Várnai
Atmos. Chem. Phys., 17, 8489–8508, https://doi.org/10.5194/acp-17-8489-2017, https://doi.org/10.5194/acp-17-8489-2017, 2017
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This study presents impact of cirrus cloud horizontal heterogeneity on simulated thermal infrared brightness temperatures at the top of the atmosphere for spatial resolutions ranging from 50 m to 10 km. The cirrus is generated by the 3DCLOUD code and the radiative transfer by the 3DMCPOL code. Brightness temperatures are mostly impacted by the horizontal transport effect and plane-parallel bias at high and coarse spatial resolutions, respectively, with a minimum around 100 m–250 m.
Zhao-Cheng Zeng, Qiong Zhang, Vijay Natraj, Jack S. Margolis, Run-Lie Shia, Sally Newman, Dejian Fu, Thomas J. Pongetti, Kam W. Wong, Stanley P. Sander, Paul O. Wennberg, and Yuk L. Yung
Atmos. Chem. Phys., 17, 2495–2508, https://doi.org/10.5194/acp-17-2495-2017, https://doi.org/10.5194/acp-17-2495-2017, 2017
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We propose a novel approach to describing the scattering effects of atmospheric aerosols using H2O retrievals in the near infrared. We found that the aerosol scattering effect is the primary contributor to the variations in the wavelength dependence of the H2O SCD retrievals and the scattering effects can be derived using H2O retrievals from multiple bands. This proposed method could potentially contribute towards reducing biases in greenhouse gas retrievals from space.
Michael Schäfer, Eike Bierwirth, André Ehrlich, Evelyn Jäkel, Frank Werner, and Manfred Wendisch
Atmos. Chem. Phys., 17, 2359–2372, https://doi.org/10.5194/acp-17-2359-2017, https://doi.org/10.5194/acp-17-2359-2017, 2017
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Cloud optical thickness fields, retrieved from solar spectral radiance measurements, are used to investigate the directional structure of horizontal cloud inhomogeneities with scalar one-dimensional inhomogeneity parameters, two-dimensional auto-correlation functions, and two-dimensional Fourier analysis. The investigations reveal that it is not sufficient to quantify horizontal cloud inhomogeneities by one-dimensional inhomogeneity parameters; two-dimensional parameters are necessary.
Quentin Libois, Liviu Ivanescu, Jean-Pierre Blanchet, Hannes Schulz, Heiko Bozem, W. Richard Leaitch, Julia Burkart, Jonathan P. D. Abbatt, Andreas B. Herber, Amir A. Aliabadi, and Éric Girard
Atmos. Chem. Phys., 16, 15689–15707, https://doi.org/10.5194/acp-16-15689-2016, https://doi.org/10.5194/acp-16-15689-2016, 2016
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The first airborne measurements performed with the FIRR are presented. Vertical profiles of upwelling spectral radiance in the far-infrared are measured in the Arctic atmosphere for the first time. They show the impact of the temperature inversion on the radiative budget of the atmosphere, especially in the far-infrared. The presence of ice clouds also significantly alters the far-infrared budget, highlighting the critical interplay between water vapour and clouds in this very dry region.
Jani Huttunen, Harri Kokkola, Tero Mielonen, Mika Esa Juhani Mononen, Antti Lipponen, Juha Reunanen, Anders Vilhelm Lindfors, Santtu Mikkonen, Kari Erkki Juhani Lehtinen, Natalia Kouremeti, Alkiviadis Bais, Harri Niska, and Antti Arola
Atmos. Chem. Phys., 16, 8181–8191, https://doi.org/10.5194/acp-16-8181-2016, https://doi.org/10.5194/acp-16-8181-2016, 2016
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For a good estimate of the current forcing by anthropogenic aerosols, knowledge in past is needed. One option to lengthen time series is to retrieve aerosol optical depth from solar radiation measurements. We have evaluated several methods for this task. Most of the methods produce aerosol optical depth estimates with a good accuracy. However, machine learning methods seem to be the most applicable not to produce any systematic biases, since they do not need constrain the aerosol properties.
Zhibo Zhang, Kerry Meyer, Hongbin Yu, Steven Platnick, Peter Colarco, Zhaoyan Liu, and Lazaros Oreopoulos
Atmos. Chem. Phys., 16, 2877–2900, https://doi.org/10.5194/acp-16-2877-2016, https://doi.org/10.5194/acp-16-2877-2016, 2016
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The frequency of occurrence and shortwave direct radiative effects (DRE) of above-cloud aerosols (ACAs) over global oceans are investigated using 8 years of collocated CALIOP and MODIS observations. We estimated that ACAs have a global ocean annual mean diurnally averaged cloudy-sky DRE of 0.015 W m−2 (range of −0.03 to 0.06 W m−2) at TOA. The DREs at surface and within atmosphere are −0.15 W m−2 (range of −0.09 to −0.21 W m−2), and 0.17 W m−2 (range of 0.11 to 0.24 W m−2), respectively.
Wenjun Tang, Jun Qin, Kun Yang, Shaomin Liu, Ning Lu, and Xiaolei Niu
Atmos. Chem. Phys., 16, 2543–2557, https://doi.org/10.5194/acp-16-2543-2016, https://doi.org/10.5194/acp-16-2543-2016, 2016
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In this paper, we develop a new method to quickly retrieve high-resolution surface solar radiation (SSR) over China by combining MODIS and MTSAT data. The RMSEs of the retrieved SSR at hourly, daily, and monthly scales are about 98.5, 34.2, and 22.1 W m−2. The accuracy is comparable to or even higher than other two satellite radiation products. Finally, we derive an 8-year high-resolution SSR data set (hourly, 5 km) from 2007 to 2014, which would contribute to studies of land surface processes.
S. Doniki, D. Hurtmans, L. Clarisse, C. Clerbaux, H. M. Worden, K. W. Bowman, and P.-F. Coheur
Atmos. Chem. Phys., 15, 12971–12987, https://doi.org/10.5194/acp-15-12971-2015, https://doi.org/10.5194/acp-15-12971-2015, 2015
W. Sun, R. R. Baize, G. Videen, Y. Hu, and Q. Fu
Atmos. Chem. Phys., 15, 11909–11918, https://doi.org/10.5194/acp-15-11909-2015, https://doi.org/10.5194/acp-15-11909-2015, 2015
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A method is reported for retrieving super-thin cloud optical depth with polarized light. It is found that near-backscatter p-polarized light is sensitive to clouds, but not to ocean conditions. Near-backscatter p-polarized intensity linearly relates to super-thin cloud optical depth. Based on these findings, super-thin cloud optical depth can be retrieved with little effect from surface reflection.
M. Schäfer, E. Bierwirth, A. Ehrlich, E. Jäkel, and M. Wendisch
Atmos. Chem. Phys., 15, 8147–8163, https://doi.org/10.5194/acp-15-8147-2015, https://doi.org/10.5194/acp-15-8147-2015, 2015
W. Sun, R. R. Baize, C. Lukashin, and Y. Hu
Atmos. Chem. Phys., 15, 7725–7734, https://doi.org/10.5194/acp-15-7725-2015, https://doi.org/10.5194/acp-15-7725-2015, 2015
E. C. Turner, H.-T. Lee, and S. F. B. Tett
Atmos. Chem. Phys., 15, 6561–6575, https://doi.org/10.5194/acp-15-6561-2015, https://doi.org/10.5194/acp-15-6561-2015, 2015
M. M. Wonsick, R. T. Pinker, and Y. Ma
Atmos. Chem. Phys., 14, 8749–8761, https://doi.org/10.5194/acp-14-8749-2014, https://doi.org/10.5194/acp-14-8749-2014, 2014
X. Ceamanos, D. Carrer, and J.-L. Roujean
Atmos. Chem. Phys., 14, 8209–8232, https://doi.org/10.5194/acp-14-8209-2014, https://doi.org/10.5194/acp-14-8209-2014, 2014
Q. Shi and S. Liang
Atmos. Chem. Phys., 14, 5659–5677, https://doi.org/10.5194/acp-14-5659-2014, https://doi.org/10.5194/acp-14-5659-2014, 2014
C. Fricke, A. Ehrlich, E. Jäkel, B. Bohn, M. Wirth, and M. Wendisch
Atmos. Chem. Phys., 14, 1943–1958, https://doi.org/10.5194/acp-14-1943-2014, https://doi.org/10.5194/acp-14-1943-2014, 2014
Y. Ma, Z. Zhu, L. Zhong, B. Wang, C. Han, Z. Wang, Y. Wang, L. Lu, P. M. Amatya, W. Ma, and Z. Hu
Atmos. Chem. Phys., 14, 1507–1515, https://doi.org/10.5194/acp-14-1507-2014, https://doi.org/10.5194/acp-14-1507-2014, 2014
W. Sun and C. Lukashin
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Short summary
We examined four summers of data from a ground-based atmospheric science instrument suite at Summit Station, Greenland, to isolate the signature of the ice precipitation. By using a combination of instruments with different specialities, we identified a passive microwave signature of the ice precipitation. This ice signature compares well to models using synthetic data characteristic of the site.
We examined four summers of data from a ground-based atmospheric science instrument suite at...
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