An improved TROPOMI tropospheric HCHO retrieval over China
Wenjing Su, Cheng Liu, Ka Lok Chan, Qihou Hu, Haoran Liu, Xiangguang Ji, Yizhi Zhu, Ting Liu, Chengxin Zhang, Yujia Chen, and Jianguo Liu
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-109,2020
Preprint under review for AMT (discussion: open, 0 comments)
The manuscript presents an improved retrieval of TROPOMI tropospheric HCHO column over China. The new retrieval optimized both slant column retrieval and air mass factor calculation for TROPOMI observations of HCHO over China. The improved TROPOMI HCHO is subsequently validated by MAX-DOAS observations. Compared to the operational product, the improved HCHO agrees better to the MAX-DOAS data and thus better suit for the analysis of regional and city scale pollution in China.
An improved TROPOMI tropospheric HCHO retrieval over China
Wenjing Su, Cheng Liu, Ka Lok Chan, Qihou Hu, Haoran Liu, Xiangguang Ji, Yizhi Zhu, Ting Liu, Chengxin Zhang, Yujia Chen, and Jianguo Liu
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-109,2020
Preprint under review for AMT (discussion: open, 0 comments)
The manuscript presents an improved retrieval of TROPOMI tropospheric HCHO column over China. The new retrieval optimized both slant column retrieval and air mass factor calculation for TROPOMI observations of HCHO over China. The improved TROPOMI HCHO is subsequently validated by MAX-DOAS observations. Compared to the operational product, the improved HCHO agrees better to the MAX-DOAS data and thus better suit for the analysis of regional and city scale pollution in China.
Shallow cumuli cover and its uncertainties from ground-based lidar–radar data and sky images
Erin A. Riley, Jessica M. Kleiss, Laura D. Riihimaki, Charles N. Long, Larry K. Berg, and Evgueni Kassianov
Atmos. Meas. Tech., 13, 2099–2117, https://doi.org/10.5194/amt-13-2099-2020, 2020
Discrepancies in hourly shallow cumuli cover estimates can be substantial. Instrument detection differences contribute to long-term bias in shallow cumuli cover estimates, whereas narrow field-of-view configurations impact measurement uncertainty as averaging time decreases. A new tool is introduced to visually assess both impacts on sub-hourly cloud cover estimates. Accurate shallow cumuli cover estimation is needed for model–observation comparisons and studying cloud-surface interactions.
Shallow cumuli cover and its uncertainties from ground-based lidar–radar data and sky images
Erin A. Riley, Jessica M. Kleiss, Laura D. Riihimaki, Charles N. Long, Larry K. Berg, and Evgueni Kassianov
Atmos. Meas. Tech., 13, 2099–2117, https://doi.org/10.5194/amt-13-2099-2020, 2020
Discrepancies in hourly shallow cumuli cover estimates can be substantial. Instrument detection differences contribute to long-term bias in shallow cumuli cover estimates, whereas narrow field-of-view configurations impact measurement uncertainty as averaging time decreases. A new tool is introduced to visually assess both impacts on sub-hourly cloud cover estimates. Accurate shallow cumuli cover estimation is needed for model–observation comparisons and studying cloud-surface interactions.
Intercomparison of wind observations from the European Space Agency's Aeolus satellite mission and the ALADIN Airborne Demonstrator
Oliver Lux, Christian Lemmerz, Fabian Weiler, Uwe Marksteiner, Benjamin Witschas, Stephan Rahm, Alexander Geiß, and Oliver Reitebuch
Atmos. Meas. Tech., 13, 2075–2097, https://doi.org/10.5194/amt-13-2075-2020, 2020
This work reports on the first airborne validation campaign of ESA’s Earth Explorer mission Aeolus, conducted in central Europe during the commissioning phase in November 2018. After presenting the methodology used to compare the data sets from the satellite, the airborne wind lidar and the ECWMF model, the wind results from the underflights performed are analyzed and discussed, providing a first assessment of the accuracy and precision of the preliminary Aeolus wind data.
Implementation of an IBBCEAS technique in an atmospheric simulation chamber for in situ NO3 monitoring: characterization and validation for kinetic studies
Axel Fouqueau, Manuela Cirtog, Mathieu Cazaunau, Edouard Pangui, Pascal Zapf, Guillaume Siour, Xavier Landsheere, Guillaume Méjean, Daniele Romanini, and Bénédicte Picquet-Varrault
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-103,2020
Preprint under review for AMT (discussion: open, 0 comments)
An incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) technique has been developed for in situ monitoring of NO3 radicals in the CSA simulation chamber (at LISA). The optical cavity allows a high sensitivity for NO3 detection up to 6 ppt for an integration time of 10 seconds. The technique is now fully operational and can be used to determine rate constants for fast reactions involving complex volatile organic compounds (with rate constants up to 10-10 cm3 molecule-1 s-1).
Microwave single scattering properties of non-spheroidal rain drops
Robin Ekelund, Patrick Eriksson, and Michael Kahnert
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-85,2020
Preprint under review for AMT (discussion: open, 0 comments)
Rain drops become flattened due to aerodynamic drag, as they increase in mass and fall-speed. The shape of such rain drops was calculated, and the electromagnetic interaction between microwave radiation and the rain drops was calculated. The calculations are made publicly available to the scientific community, in order to promote accurate representations of rain drops in measurements. Tests show that the drop shape can indeed have a noticeable effect on microwave observations of heavy rainfall.
Uncertainty Quantification for Atmospheric Motion Vectors with Machine Learning
Joaquim V. Teixeira, Hai Nguyen, Derek J. Posselt, Hui Su, and Longtao Wu
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-95,2020
Preprint under review for AMT (discussion: open, 0 comments)
Wind-tracking algorithms produce atmospheric motion vectors (AMVs) by tracking satellite observations. Accurately characterizing the uncertainties in AMVs is essential in assimilating them into data assimilation models. We develop a machine learning based approach for error characterization which involves gaussian mixture model clustering and random forest using a simulation dataset of water vapor, AMVs, and true winds. We show that our method improves on existing AMV error characterizations.
Intercomparison of wind observations from the European Space Agency's Aeolus satellite mission and the ALADIN Airborne Demonstrator
Oliver Lux, Christian Lemmerz, Fabian Weiler, Uwe Marksteiner, Benjamin Witschas, Stephan Rahm, Alexander Geiß, and Oliver Reitebuch
Atmos. Meas. Tech., 13, 2075–2097, https://doi.org/10.5194/amt-13-2075-2020, 2020
This work reports on the first airborne validation campaign of ESA’s Earth Explorer mission Aeolus, conducted in central Europe during the commissioning phase in November 2018. After presenting the methodology used to compare the data sets from the satellite, the airborne wind lidar and the ECWMF model, the wind results from the underflights performed are analyzed and discussed, providing a first assessment of the accuracy and precision of the preliminary Aeolus wind data.
Implementation of an IBBCEAS technique in an atmospheric simulation chamber for in situ NO3 monitoring: characterization and validation for kinetic studies
Axel Fouqueau, Manuela Cirtog, Mathieu Cazaunau, Edouard Pangui, Pascal Zapf, Guillaume Siour, Xavier Landsheere, Guillaume Méjean, Daniele Romanini, and Bénédicte Picquet-Varrault
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-103,2020
Preprint under review for AMT (discussion: open, 0 comments)
An incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) technique has been developed for in situ monitoring of NO3 radicals in the CSA simulation chamber (at LISA). The optical cavity allows a high sensitivity for NO3 detection up to 6 ppt for an integration time of 10 seconds. The technique is now fully operational and can be used to determine rate constants for fast reactions involving complex volatile organic compounds (with rate constants up to 10-10 cm3 molecule-1 s-1).
Microwave single scattering properties of non-spheroidal rain drops
Robin Ekelund, Patrick Eriksson, and Michael Kahnert
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-85,2020
Preprint under review for AMT (discussion: open, 0 comments)
Rain drops become flattened due to aerodynamic drag, as they increase in mass and fall-speed. The shape of such rain drops was calculated, and the electromagnetic interaction between microwave radiation and the rain drops was calculated. The calculations are made publicly available to the scientific community, in order to promote accurate representations of rain drops in measurements. Tests show that the drop shape can indeed have a noticeable effect on microwave observations of heavy rainfall.
Uncertainty Quantification for Atmospheric Motion Vectors with Machine Learning
Joaquim V. Teixeira, Hai Nguyen, Derek J. Posselt, Hui Su, and Longtao Wu
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-95,2020
Preprint under review for AMT (discussion: open, 0 comments)
Wind-tracking algorithms produce atmospheric motion vectors (AMVs) by tracking satellite observations. Accurately characterizing the uncertainties in AMVs is essential in assimilating them into data assimilation models. We develop a machine learning based approach for error characterization which involves gaussian mixture model clustering and random forest using a simulation dataset of water vapor, AMVs, and true winds. We show that our method improves on existing AMV error characterizations.
Mind-the-gap Part II: Improving quantitative estimates of cloud and rain water path in oceanic warm rain using spaceborne radars
Alessandro Battaglia, Pavlos Kollias, Ranvir Dhillon, Katia Lamer, Marat Khairoutdinov, and Daniel Watters
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-80,2020
Preprint under review for AMT (discussion: open, 0 comments)
Warm rain accounts for slightly more than 30 % of the total rain amount and 70 % of the total rain area in the tropical belt and usually appears in kilometre-size cells. Space-borne radars adopting millimetre wavelengths are excellent tools for detecting such precipitation type and in separating between the cloud and rain components. Our work highlights the benefits of operating multi-frequency radars and discuss the impact of antenna footprints in quantitative estimates of liquid water paths.
Mind-the-gap Part II: Improving quantitative estimates of cloud and rain water path in oceanic warm rain using spaceborne radars
Alessandro Battaglia, Pavlos Kollias, Ranvir Dhillon, Katia Lamer, Marat Khairoutdinov, and Daniel Watters
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-80,2020
Preprint under review for AMT (discussion: open, 0 comments)
Warm rain accounts for slightly more than 30 % of the total rain amount and 70 % of the total rain area in the tropical belt and usually appears in kilometre-size cells. Space-borne radars adopting millimetre wavelengths are excellent tools for detecting such precipitation type and in separating between the cloud and rain components. Our work highlights the benefits of operating multi-frequency radars and discuss the impact of antenna footprints in quantitative estimates of liquid water paths.
Using Two-Stream Theory to Capture Fluctuations of Satellite-Perceived TOA SW Radiances Reflected from Clouds over Ocean
Florian Tornow, Carlos Domenech, Howard W. Barker, René Preusker, and Jürgen Fischer
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-149,2020
Preprint under review for AMT (discussion: open, 0 comments)
Clouds reflect sunlight unevenly which makes it difficult to quantify the portion reflected back to space via satellite observation. To improve quantification, we propose a new statistical model that incorporates more satellite-inferred cloud and atmospheric properties than state-of-the-art models. We use concepts from radiative transfer theory that we statistically optimize to fit observations. The new model often explains past satellite observations better and predicts reflection plausibly.
Emission Monitoring Mobile Experiment (EMME): an overview and first results of the St. Petersburg megacity campaign-2019
Maria V. Makarova, Carlos Alberti, Dmitry V. Ionov, Frank Hase, Stefani C. Foka, Thomas Blumenstock, Thorsten Warneke, Yana A. Virolainen, Vladimir S. Kostsov, Matthias Frey, Anatoly V. Poberovskii, Yuri M. Timofeyev, Nina N. Paramonova, Kristina A. Volkova, Nikita A. Zaitsev, Egor Y. Biryukov, Sergey I. Osipov, Boris K. Makarov, Alexander V. Polyakov, Viktor M. Ivakhov, Hamud Kh. Imhasin, and Eugene F. Mikhailov
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-87,2020
Preprint under review for AMT (discussion: open, 0 comments)
Fundamental understanding of the major processes driving climate change is the key problem which is to be solved not only on a global but also on regional scales. The Emission Monitoring Mobile Experiment (EMME) carried out in 2019 with two portable spectrometers Bruker EM27/SUN as core instruments provided new information on the emissions of greenhouse (CO2, CH4) and reactive (CO, NOx) gases from St. Petersburg (Russia) which is the largest northern megacity with the population of 5 million.
Using Two-Stream Theory to Capture Fluctuations of Satellite-Perceived TOA SW Radiances Reflected from Clouds over Ocean
Florian Tornow, Carlos Domenech, Howard W. Barker, René Preusker, and Jürgen Fischer
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-149,2020
Preprint under review for AMT (discussion: open, 0 comments)
Clouds reflect sunlight unevenly which makes it difficult to quantify the portion reflected back to space via satellite observation. To improve quantification, we propose a new statistical model that incorporates more satellite-inferred cloud and atmospheric properties than state-of-the-art models. We use concepts from radiative transfer theory that we statistically optimize to fit observations. The new model often explains past satellite observations better and predicts reflection plausibly.
Emission Monitoring Mobile Experiment (EMME): an overview and first results of the St. Petersburg megacity campaign-2019
Maria V. Makarova, Carlos Alberti, Dmitry V. Ionov, Frank Hase, Stefani C. Foka, Thomas Blumenstock, Thorsten Warneke, Yana A. Virolainen, Vladimir S. Kostsov, Matthias Frey, Anatoly V. Poberovskii, Yuri M. Timofeyev, Nina N. Paramonova, Kristina A. Volkova, Nikita A. Zaitsev, Egor Y. Biryukov, Sergey I. Osipov, Boris K. Makarov, Alexander V. Polyakov, Viktor M. Ivakhov, Hamud Kh. Imhasin, and Eugene F. Mikhailov
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-87,2020
Preprint under review for AMT (discussion: open, 0 comments)
Fundamental understanding of the major processes driving climate change is the key problem which is to be solved not only on a global but also on regional scales. The Emission Monitoring Mobile Experiment (EMME) carried out in 2019 with two portable spectrometers Bruker EM27/SUN as core instruments provided new information on the emissions of greenhouse (CO2, CH4) and reactive (CO, NOx) gases from St. Petersburg (Russia) which is the largest northern megacity with the population of 5 million.
Aerosol optical properties as observed from an ultralight aircraft over the Strait of Gibraltar
Patrick Chazette
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-131,2020
Preprint under review for AMT (discussion: open, 0 comments)
By coupling airborne lidar and ground-based lidar measurements, this paper highlights the aerosol transport over the Strait of Gibraltar. It shows that the lidar-derived aerosol optical properties can be different from what is commonly accepted. It presents unprecedented vertical profiles over this region and relates them to the origin of air masses. The results are based on ground, airborne and spaceborne observations, as well as multiple retro trajectories analysis.
Aerosol optical properties as observed from an ultralight aircraft over the Strait of Gibraltar
Patrick Chazette
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-131,2020
Preprint under review for AMT (discussion: open, 0 comments)
By coupling airborne lidar and ground-based lidar measurements, this paper highlights the aerosol transport over the Strait of Gibraltar. It shows that the lidar-derived aerosol optical properties can be different from what is commonly accepted. It presents unprecedented vertical profiles over this region and relates them to the origin of air masses. The results are based on ground, airborne and spaceborne observations, as well as multiple retro trajectories analysis.
