Ground-based FTIR O3 retrievals from the 3040 cm−1 spectral
range at Xianghe, China
Minqiang Zhou, Pucai Wang, Bavo Langerock, Corinne Vigouroux, Christian Hermans, Nicolas Kumps, Ting Wang, Yang Yang, Denghui Ji, Liang Ran, Jinqiang Zhang, Yuejian Xuan, Hongbin Chen, Françoise Posny, Valentin Duflot, Jean-Marc Metzger, and Martine De Mazière
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-127,2020
Preprint under review for AMT (discussion: open, 0 comments)
We study O3 retrievals in the 3040 cm−1 spectral range from FTIR measurements at Xianghe China (39.75N, 116.96E, 50 m a.s.l.) between June 2018 and December 2019. It is found that the FTIR O3 (3040 cm−1) retrievals capture very well the seasonal and synoptic variations of O3. The systematic and random uncertainties of FTIR O3 (3040 cm−1) total column are about 5.5–9.0 % and 1.4%, respectively. The DOF is 2.4±0.3 (1σ), with 2 individual pieces of information in surface-20 km and 20–40 km.
An inter-laboratory comparison of aerosol in organic ion measurements by Ion Chromatography: implications for aerosol pH estimate
Jingsha Xu, Shaojie Song, Roy M. Harrison, Congbo Song, Lianfang Wei, Qiang Zhang, Yele Sun, Lu Lei, Chao Zhang, Xiaohong Yao, Dihui Chen, Weijun Li, Miaomiao Wu, Hezhong Tian, Lining Luo, Shengrui Tong, Weiran Li, Junling Wang, Guoliang Shi, Yanqi Huangfu, Yingze Tian, Baozhu Ge, Shaoli Su, Chao Peng, Yang Chen, Fumo Yang, Aleksandra Mihajlidi-Zelić, Dragana Đorđević, Stefan J. Swift, Imogen Andrews, Jacqueline F. Hamilton, Ye Sun, Agung Kramawijaya, Jinxiu Han, Supattarachai Saksakulkrai, Clarissa Baldo, Siqi Hou, Feixue Zheng, Kaspar R. Daellenbach, Chao Yan, Yongchun Liu, Markku Kulmala, Pingqing Fu, and Zongbo Shi
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-156,2020
Preprint under review for AMT (discussion: open, 0 comments)
An inter-laboratory comparison exercise was conducted for the first time to examine the difference of water-soluble inorganic ions (WSII) measured by 10 labs using Ion Chromatography and by 2 online Aerosol Chemical Speciation Monitor method. Major ions including SO42−, NO3−, NH4+ agreed well in 10 IC labs, and correlated well with ACSM. WSII inter-lab variability strongly affected aerosol acidity results based on ion balance, but aerosol pH computed by ISORROPIA-II were very similar.
Detecting turbulent structures on single Doppler lidar large datasets: an automated classification method for horizontal scans
Ioannis Cheliotis, Elsa Dieudonné, Hervé Delbarre, Anton Sokolov, Egor Dmitriev, Patrick Augustin, and Marc Fourmentin
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-82,2020
Preprint under review for AMT (discussion: open, 0 comments)
The current study presents an automated method to classify turbulent structures near the surface, based on the observations recorded by a single scanning Doppler lidar. This methodology combines texture analysis with a supervised machine learning algorithm in order to study large datasets. The algorithm classified correctly about 91 % cases of a training ensemble (150 scans). Furthermore the results of a two-months classified dataset (4577 scans) by the algorithm are presented.
Assessment of the quality of TROPOMI high-spatial-resolution NO2 data products in the Greater Toronto Area
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Alexander Cede, Martin Tiefengraber, Moritz Müller, Kristof Bognar, Kimberly Strong, Folkert Boersma, Henk Eskes, Jonathan Davies, Akira Ogyu, and Sum Chi Lee
Atmos. Meas. Tech., 13, 2131–2159, https://doi.org/10.5194/amt-13-2131-2020, 2020
Pandora NO2 measurements made at three sites located in the Toronto area are used to evaluate the TROPOspheric Monitoring Instrument (TROPOMI) NO2 data products, including standard NO2 and research data developed using a high-resolution regional air quality forecast model. TROPOMI pixels located upwind and downwind from the Pandora sites were analyzed by a new wind-based validation method, which revealed the spatial patterns of local and transported emissions and regional air quality changes.
Assessment of the quality of TROPOMI high-spatial-resolution NO2 data products in the Greater Toronto Area
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Alexander Cede, Martin Tiefengraber, Moritz Müller, Kristof Bognar, Kimberly Strong, Folkert Boersma, Henk Eskes, Jonathan Davies, Akira Ogyu, and Sum Chi Lee
Atmos. Meas. Tech., 13, 2131–2159, https://doi.org/10.5194/amt-13-2131-2020, 2020
Pandora NO2 measurements made at three sites located in the Toronto area are used to evaluate the TROPOspheric Monitoring Instrument (TROPOMI) NO2 data products, including standard NO2 and research data developed using a high-resolution regional air quality forecast model. TROPOMI pixels located upwind and downwind from the Pandora sites were analyzed by a new wind-based validation method, which revealed the spatial patterns of local and transported emissions and regional air quality changes.
Detecting turbulent structures on single Doppler lidar large datasets: an automated classification method for horizontal scans
Ioannis Cheliotis, Elsa Dieudonné, Hervé Delbarre, Anton Sokolov, Egor Dmitriev, Patrick Augustin, and Marc Fourmentin
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-82,2020
Preprint under review for AMT (discussion: open, 0 comments)
The current study presents an automated method to classify turbulent structures near the surface, based on the observations recorded by a single scanning Doppler lidar. This methodology combines texture analysis with a supervised machine learning algorithm in order to study large datasets. The algorithm classified correctly about 91 % cases of a training ensemble (150 scans). Furthermore the results of a two-months classified dataset (4577 scans) by the algorithm are presented.
Validation of acetonitrile (CH3CN) measurements in the stratosphere and lower mesosphere from the SMILES instrument on the International Space Station
Tamaki Fujinawa, Tomohiro O. Sato, Takayoshi Yamada, Seidai Nara, Yuki Uchiyama, Kodai Takahashi, Naohiro Yoshida, and Yasuko Kasai
Atmos. Meas. Tech., 13, 2119–2129, https://doi.org/10.5194/amt-13-2119-2020, 2020
We performed an error analysis of SMILES observations for acetonitrile and a validation using the MLS observations by extracting the coincident points between SMILES and MLS data. The major error sources for the SMILES observations were quantitatively estimated. At upper pressure levels the difference between the two datasets increased because of an uncertainty in MLS observations. The results showed that SMILES has an advantage in measuring acetonitrile in the upper stratosphere and mesosphere.
Retrieval of daytime mesospheric ozone using OSIRIS observation of O2(a1∆g) emission
Anqi Li, Chris Roth, Kristell Pérot, Ole Martin Christensen, Adam M. Bourassa, Doug Degenstein, and Donal Murtagh
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-56,2020
Preprint under review for AMT (discussion: open, 0 comments)
Improving knowledge of the ozone global distributions in the mesosphere-lower thermosphere (MLT) is a crucial step in understanding the behaviour of the middle atmosphere. However, the ozone concentration under sunlit conditions in the MLT is often so low that its measurement requires instruments with very high sensitivity. Fortunately, the bright oxygen airglow can serve as a proxy to retrieve the daytime ozone density indirectly, due to the strong connection to ozone photolysis in the Hartley band. The OSIRIS IR imager (hereafter IRI), one of the instruments on the Odin satellite, routinely measures the oxygen infrared atmospheric band (IRA band) at 1.27 μm. In this paper, we will describe the detailed steps of retrieving the calibrated IRA band limb radiance, the volume emission rate of O2(a1∆g) and, finally, the ozone number density. This retrieval technique is applied to a one-year-sample IRI dataset. The resulting product is a completely new ozone dataset with very high along-track resolution. The performance of the retrieval technique is demonstrated by a comparison of the coincident ozone measurements from the same spacecraft, as well as zonal mean and monthly average comparisons between OS, SMR, MIPAS and ACE-FTS. The consistency of this IRI ozone dataset implies that such a retrieval technique can be further applied to all the measurements made throughout the 19 years-long mission, leading to a long-term, high resolution dataset in the middle atmosphere.
Validation of acetonitrile (CH3CN) measurements in the stratosphere and lower mesosphere from the SMILES instrument on the International Space Station
Tamaki Fujinawa, Tomohiro O. Sato, Takayoshi Yamada, Seidai Nara, Yuki Uchiyama, Kodai Takahashi, Naohiro Yoshida, and Yasuko Kasai
Atmos. Meas. Tech., 13, 2119–2129, https://doi.org/10.5194/amt-13-2119-2020, 2020
We performed an error analysis of SMILES observations for acetonitrile and a validation using the MLS observations by extracting the coincident points between SMILES and MLS data. The major error sources for the SMILES observations were quantitatively estimated. At upper pressure levels the difference between the two datasets increased because of an uncertainty in MLS observations. The results showed that SMILES has an advantage in measuring acetonitrile in the upper stratosphere and mesosphere.
Retrieval of daytime mesospheric ozone using OSIRIS observation of O2(a1∆g) emission
Anqi Li, Chris Roth, Kristell Pérot, Ole Martin Christensen, Adam M. Bourassa, Doug Degenstein, and Donal Murtagh
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-56,2020
Preprint under review for AMT (discussion: open, 0 comments)
Improving knowledge of the ozone global distributions in the mesosphere-lower thermosphere (MLT) is a crucial step in understanding the behaviour of the middle atmosphere. However, the ozone concentration under sunlit conditions in the MLT is often so low that its measurement requires instruments with very high sensitivity. Fortunately, the bright oxygen airglow can serve as a proxy to retrieve the daytime ozone density indirectly, due to the strong connection to ozone photolysis in the Hartley band. The OSIRIS IR imager (hereafter IRI), one of the instruments on the Odin satellite, routinely measures the oxygen infrared atmospheric band (IRA band) at 1.27 μm. In this paper, we will describe the detailed steps of retrieving the calibrated IRA band limb radiance, the volume emission rate of O2(a1∆g) and, finally, the ozone number density. This retrieval technique is applied to a one-year-sample IRI dataset. The resulting product is a completely new ozone dataset with very high along-track resolution. The performance of the retrieval technique is demonstrated by a comparison of the coincident ozone measurements from the same spacecraft, as well as zonal mean and monthly average comparisons between OS, SMR, MIPAS and ACE-FTS. The consistency of this IRI ozone dataset implies that such a retrieval technique can be further applied to all the measurements made throughout the 19 years-long mission, leading to a long-term, high resolution dataset in the middle atmosphere.
Effects of clouds on the UV Absorbing Aerosol Index from TROPOMI
Maurits L. Kooreman, Piet Stammes, Victor Trees, Maarten Sneep, L. Gijsbert Tilstra, Martin de Graaf, Deborah C. Stein Zweers, Ping Wang, Olaf N. E. Tuinder, and J. Pepijn Veefkind
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-112,2020
Preprint under review for AMT (discussion: open, 0 comments)
We investigated the influence of clouds on the AAI, which is an indicator of the presence of small particles suspended in the atmosphere. Clouds produce artefacts in the AAI calculation on the individual measurement (7 km) scale, which was not seen with previous instruments, as well as large (1000+ km) scales. To reduce these artefacts, we used three different AAI calculation techniques with varying complexity. We find that the AAI artefacts are reduced when using more complex techniques.
Retrieval of Lower-Order Moments of the Drop Size Distribution using CSU-CHILL X-band Polarimetric Radar: A Case Study
Viswanathan Bringi, Kumar Vijay Mishra, Merhala Thurai, Patrick C. Kennedy, and Timothy H. Raupach
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-160,2020
Preprint under review for AMT (discussion: open, 0 comments)
The raindrop size distribution and its moments are fundamental in many areas such as radar measurement of rainfall using polarimetry and numerical modelling of the microphysical processes of rain formation and evolution. We develop a technique which uses advanced radar measurements and complete drop size distributions using two collocated instruments to retrieve the lower order moments such as total drop concentration and rain water content. We demonstrate proof-of-concept using a case study.
Probabilistic analysis of ambiguities in radar echo direction of
arrival from meteors
Daniel Kastinen and Johan Kero
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-157,2020
Preprint under review for AMT (discussion: open, 0 comments)
The behavior of position determination with interferometric radar systems and possible ambiguities therein depend on the spatial configuration of the radar receiving antennas and their individual characteristics. We have simulated the position determination performance of five different radar systems. These simulation showed that ambiguities are dynamic and need to be examined on a case by case basis. However, the simulations can be used to analyse and understand previously ambiguous data.
Effects of clouds on the UV Absorbing Aerosol Index from TROPOMI
Maurits L. Kooreman, Piet Stammes, Victor Trees, Maarten Sneep, L. Gijsbert Tilstra, Martin de Graaf, Deborah C. Stein Zweers, Ping Wang, Olaf N. E. Tuinder, and J. Pepijn Veefkind
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-112,2020
Preprint under review for AMT (discussion: open, 0 comments)
We investigated the influence of clouds on the AAI, which is an indicator of the presence of small particles suspended in the atmosphere. Clouds produce artefacts in the AAI calculation on the individual measurement (7 km) scale, which was not seen with previous instruments, as well as large (1000+ km) scales. To reduce these artefacts, we used three different AAI calculation techniques with varying complexity. We find that the AAI artefacts are reduced when using more complex techniques.
Retrieval of Lower-Order Moments of the Drop Size Distribution using CSU-CHILL X-band Polarimetric Radar: A Case Study
Viswanathan Bringi, Kumar Vijay Mishra, Merhala Thurai, Patrick C. Kennedy, and Timothy H. Raupach
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-160,2020
Preprint under review for AMT (discussion: open, 0 comments)
The raindrop size distribution and its moments are fundamental in many areas such as radar measurement of rainfall using polarimetry and numerical modelling of the microphysical processes of rain formation and evolution. We develop a technique which uses advanced radar measurements and complete drop size distributions using two collocated instruments to retrieve the lower order moments such as total drop concentration and rain water content. We demonstrate proof-of-concept using a case study.
Probabilistic analysis of ambiguities in radar echo direction of
arrival from meteors
Daniel Kastinen and Johan Kero
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-157,2020
Preprint under review for AMT (discussion: open, 0 comments)
The behavior of position determination with interferometric radar systems and possible ambiguities therein depend on the spatial configuration of the radar receiving antennas and their individual characteristics. We have simulated the position determination performance of five different radar systems. These simulation showed that ambiguities are dynamic and need to be examined on a case by case basis. However, the simulations can be used to analyse and understand previously ambiguous data.
Removing spurious inertial instability signals from gravity wave
temperature perturbations using spectral filtering methods
Cornelia Strube, Manfred Ern, Peter Preusse, and Martin Riese
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-29,2020
Preprint under review for AMT (discussion: open, 1 comment)
We present how inertial instabilities affect gravity wave background removals on different temperature data sets. Vertical filtering has to remove a part of the gravity wave spectrum to eliminate inertial instability remnants, while horizontal filtering leaves typical gravity wave scales untouched. In addition, we show that it is possible to separate inertial instabilities from gravity wave perturbations for infrared limb-sounding satellite profiles using a cutoff zonal wavenumber of 6.
Combining low-cost, surface-based aerosol monitors with
size-resolved satellite data for air quality applications
Priyanka deSouza, Ralph A. Kahn, James A. Limbacher, Eloise A. Marais, Fábio Duarte, and Carlo Ratti
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-136,2020
Preprint under review for AMT (discussion: open, 0 comments)
This paper presents a novel method to calibrate satellite data using low-cost optical particle counters (OPCs) to develop higher quality particulate matter (PM) estimates. This method could enable cities that do not have access to expensive reference air quality monitors, many of which are in the global South, to develop locally calibrated PM estimates from satellite data. Such information can be crucial for the development of effective air quality management plans.
Combining low-cost, surface-based aerosol monitors with
size-resolved satellite data for air quality applications
Priyanka deSouza, Ralph A. Kahn, James A. Limbacher, Eloise A. Marais, Fábio Duarte, and Carlo Ratti
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-136,2020
Preprint under review for AMT (discussion: open, 0 comments)
This paper presents a novel method to calibrate satellite data using low-cost optical particle counters (OPCs) to develop higher quality particulate matter (PM) estimates. This method could enable cities that do not have access to expensive reference air quality monitors, many of which are in the global South, to develop locally calibrated PM estimates from satellite data. Such information can be crucial for the development of effective air quality management plans.
Removing spurious inertial instability signals from gravity wave
temperature perturbations using spectral filtering methods
Cornelia Strube, Manfred Ern, Peter Preusse, and Martin Riese
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-29,2020
Preprint under review for AMT (discussion: open, 1 comment)
We present how inertial instabilities affect gravity wave background removals on different temperature data sets. Vertical filtering has to remove a part of the gravity wave spectrum to eliminate inertial instability remnants, while horizontal filtering leaves typical gravity wave scales untouched. In addition, we show that it is possible to separate inertial instabilities from gravity wave perturbations for infrared limb-sounding satellite profiles using a cutoff zonal wavenumber of 6.
