Articles | Volume 34, issue 2
https://doi.org/10.5194/angeo-34-279-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/angeo-34-279-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Atmospheric CO2 source and sink patterns over the Indian region
Suvarna Fadnavis
Centre for Climate Change Research, Indian Institute of Tropical Meteorology, Pune, India
K. Ravi Kumar
Department of Environmental and Geochemical Cycle Research, JAMSTEC, Yokohama, Japan
National Institute of Polar Research, Tokyo, Japan
Yogesh K. Tiwari
CORRESPONDING AUTHOR
Centre for Climate Change Research, Indian Institute of Tropical Meteorology, Pune, India
Luca Pozzoli
Eurasia Institute of Earth Sciences, Istanbul Technical University, Istanbul, Turkey
Related authors
Yasin Elshorbany, Jerald R. Ziemke, Sarah Strode, Hervé Petetin, Kazuyuki Miyazaki, Isabelle De Smedt, Kenneth Pickering, Rodrigo J. Seguel, Helen Worden, Tamara Emmerichs, Domenico Taraborrelli, Maria Cazorla, Suvarna Fadnavis, Rebecca R. Buchholz, Benjamin Gaubert, Néstor Y. Rojas, Thiago Nogueira, Thérèse Salameh, and Min Huang
Atmos. Chem. Phys., 24, 12225–12257, https://doi.org/10.5194/acp-24-12225-2024, https://doi.org/10.5194/acp-24-12225-2024, 2024
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Short summary
We investigated tropospheric ozone spatial variability and trends from 2005 to 2019 and related those to ozone precursors on global and regional scales. We also investigate the spatiotemporal characteristics of the ozone formation regime in relation to ozone chemical sources and sinks. Our analysis is based on remote sensing products of the tropospheric column of ozone and its precursors, nitrogen dioxide, formaldehyde, and total column CO, as well as ozonesonde data and model simulations.
Suvarna Fadnavis, Yasin Elshorbany, Jerald Ziemke, Brice Barret, Alexandru Rap, P. R. Satheesh Chandran, Richard Pope, Vijay Sagar, Domenico Taraborrelli, Eric Le Flochmoen, Juan Cuesta, Catherine Wespes, Folkert Boersma, Isolde Glissenaar, Isabelle De Smedt, Michel Van Roozendael, Hervé Petetin, and Isidora Anglou
EGUsphere, https://doi.org/10.5194/egusphere-2024-3050, https://doi.org/10.5194/egusphere-2024-3050, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Satellites and model simulations show enhancement in tropospheric ozone, which is highly impacted by human-produced Nitrous oxides compared to volatile organic compounds. The increased amount of ozone enhances ozone radiative forcing. The ozone enhancement and associated radiative forcing are highest over South and East Asia. The emissions of Nitrous oxides show a higher influence in shifting ozone photochemical regimes than volatile organic compounds.
Jan Clemens, Bärbel Vogel, Lars Hoffmann, Sabine Griessbach, Nicole Thomas, Suvarna Fadnavis, Rolf Müller, Thomas Peter, and Felix Ploeger
Atmos. Chem. Phys., 24, 763–787, https://doi.org/10.5194/acp-24-763-2024, https://doi.org/10.5194/acp-24-763-2024, 2024
Short summary
Short summary
The source regions of the Asian tropopause aerosol layer (ATAL) are debated. We use balloon-borne measurements of the layer above Nainital (India) in August 2016 and atmospheric transport models to find ATAL source regions. Most air originated from the Tibetan plateau. However, the measured ATAL was stronger when more air originated from the Indo-Gangetic Plain and weaker when more air originated from the Pacific. Hence, the results indicate important anthropogenic contributions to the ATAL.
Suvarna Fadnavis, Bernd Heinold, T. P. Sabin, Anne Kubin, Katty Huang, Alexandru Rap, and Rolf Müller
Atmos. Chem. Phys., 23, 10439–10449, https://doi.org/10.5194/acp-23-10439-2023, https://doi.org/10.5194/acp-23-10439-2023, 2023
Short summary
Short summary
The influence of the COVID-19 lockdown on the Himalayas caused increases in snow cover and a decrease in runoff, ultimately leading to an enhanced snow water equivalent. Our findings highlight that, out of the two processes causing a retreat of Himalayan glaciers – (1) slow response to global climate change and (2) fast response to local air pollution – a policy action on the latter is more likely to be within the reach of possible policy action to help billions of people in southern Asia.
Suvarna Fadnavis, Prashant Chavan, Akash Joshi, Sunil M. Sonbawne, Asutosh Acharya, Panuganti C. S. Devara, Alexandru Rap, Felix Ploeger, and Rolf Müller
Atmos. Chem. Phys., 22, 7179–7191, https://doi.org/10.5194/acp-22-7179-2022, https://doi.org/10.5194/acp-22-7179-2022, 2022
Short summary
Short summary
We show that large amounts of anthropogenic aerosols are transported from South Asia to the northern Indian Ocean. These aerosols are then lifted into the UTLS by the ascending branch of the Hadley circulation. They are further transported to the Southern Hemisphere and downward via westerly ducts over the tropical Atlantic and Pacific. These aerosols increase tropospheric heating, resulting in an increase in water vapor, which is then transported to the UTLS.
Prashant Chavan, Suvarna Fadnavis, Tanusri Chakroborty, Christopher E. Sioris, Sabine Griessbach, and Rolf Müller
Atmos. Chem. Phys., 21, 14371–14384, https://doi.org/10.5194/acp-21-14371-2021, https://doi.org/10.5194/acp-21-14371-2021, 2021
Short summary
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Biomass burning (BB) over Asia is a strong source of carbonaceous aerosols during spring. Here, we show an outflow of Asian BB carbonaceous aerosols into the UTLS. These aerosols enhance atmospheric heating and produce circulation changes that lead to the enhancement of water vapor in the UTLS over the tropics. In the stratosphere, water vapor is further transported to the South Pole by the Brewer–Dobson circulation. Enhancement of water vapor in the UTLS has implications for climate change.
Teresa Jorge, Simone Brunamonti, Yann Poltera, Frank G. Wienhold, Bei P. Luo, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, Susanne Körner, Ruud Dirksen, Manish Naja, Suvarna Fadnavis, and Thomas Peter
Atmos. Meas. Tech., 14, 239–268, https://doi.org/10.5194/amt-14-239-2021, https://doi.org/10.5194/amt-14-239-2021, 2021
Short summary
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Balloon-borne frost point hygrometers are crucial for the monitoring of water vapour in the upper troposphere and lower stratosphere. We found that when traversing a mixed-phase cloud with big supercooled droplets, the intake tube of the instrument collects on its inner surface a high percentage of these droplets. The newly formed ice layer will sublimate at higher levels and contaminate the measurement. The balloon is also a source of contamination, but only at higher levels during the ascent.
Sreeharsha Hanumanthu, Bärbel Vogel, Rolf Müller, Simone Brunamonti, Suvarna Fadnavis, Dan Li, Peter Ölsner, Manish Naja, Bhupendra Bahadur Singh, Kunchala Ravi Kumar, Sunil Sonbawne, Hannu Jauhiainen, Holger Vömel, Beiping Luo, Teresa Jorge, Frank G. Wienhold, Ruud Dirkson, and Thomas Peter
Atmos. Chem. Phys., 20, 14273–14302, https://doi.org/10.5194/acp-20-14273-2020, https://doi.org/10.5194/acp-20-14273-2020, 2020
Short summary
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During boreal summer, anthropogenic sources yield the Asian Tropopause Aerosol Layer (ATAL), found in Asia between about 13 and 18 km altitude. Balloon-borne measurements of the ATAL conducted in northern India in 2016 show the strong variability of the ATAL. To explain its observed variability, model simulations are performed to deduce the origin of air masses on the Earth's surface, which is important to develop recommendations for regulations of anthropogenic surface emissions of the ATAL.
Suvarna Fadnavis, Rolf Müller, Gayatry Kalita, Matthew Rowlinson, Alexandru Rap, Jui-Lin Frank Li, Blaž Gasparini, and Anton Laakso
Atmos. Chem. Phys., 19, 9989–10008, https://doi.org/10.5194/acp-19-9989-2019, https://doi.org/10.5194/acp-19-9989-2019, 2019
Short summary
Short summary
This paper highlights the impact of Asian anthropogenic emission changes in SO2 on sulfate loading in the Asian upper troposphere–lower stratosphere from a global chemistry–climate model and satellite remote sensing. Estimated seasonal mean direct radiative forcing at the top of the atmosphere induced by the increase in Indian SO2 is −0.2–−1.5 W m2 over India. Chinese SO2 emission reduction leads to a positive radiative forcing of ~0.6–6 W m2 over China. It will likely decrease Indian rainfall.
Simone Brunamonti, Teresa Jorge, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, K. Ravi Kumar, Sunil Sonbawne, Susanne Meier, Deepak Singh, Frank G. Wienhold, Bei Ping Luo, Maxi Boettcher, Yann Poltera, Hannu Jauhiainen, Rijan Kayastha, Jagadishwor Karmacharya, Ruud Dirksen, Manish Naja, Markus Rex, Suvarna Fadnavis, and Thomas Peter
Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, https://doi.org/10.5194/acp-18-15937-2018, 2018
Short summary
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Based on balloon-borne measurements performed in India and Nepal in 2016–2017, we infer the vertical distributions of water vapor, ozone and aerosols in the atmosphere, from the surface to 30 km altitude. Our measurements show that the atmospheric dynamics of the Asian summer monsoon system over the polluted Indian subcontinent lead to increased concentrations of water vapor and aerosols in the high atmosphere (approximately 14–20 km altitude), which can have an important effect on climate.
Suvarna Fadnavis, Chaitri Roy, Rajib Chattopadhyay, Christopher E. Sioris, Alexandru Rap, Rolf Müller, K. Ravi Kumar, and Raghavan Krishnan
Atmos. Chem. Phys., 18, 11493–11506, https://doi.org/10.5194/acp-18-11493-2018, https://doi.org/10.5194/acp-18-11493-2018, 2018
Short summary
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Rapid industrialization, traffic growth and urbanization resulted in a significant increase in the tropospheric trace gases over Asia. There is global concern about rising levels of these trace gases. The monsoon convection transports these gases to the upper-level-anticyclone. In this study, we show transport of these gases to the extratropics via eddy-shedding from the anticyclone. We also deliberate on changes in ozone heating rates due to the transport of Asian trace gases.
Suvarna Fadnavis, Gayatry Kalita, K. Ravi Kumar, Blaž Gasparini, and Jui-Lin Frank Li
Atmos. Chem. Phys., 17, 11637–11654, https://doi.org/10.5194/acp-17-11637-2017, https://doi.org/10.5194/acp-17-11637-2017, 2017
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In this study, the model simulations show that monsoon convection over the Bay of Bengal, the South China Sea and southern flanks of the Himalayas transports Asian carbonaceous aerosol into the UTLS. Carbonaceous aerosol induces enhancement in heating rate, vertical velocity and water vapor transport in the UTLS. Doubling of carbonaceous aerosols creates an anomalous warming over the TP. It generates monsoon Hadley circulation and thus increases precipitation over India and northeast China.
Chaitri Roy, Suvarna Fadnavis, Rolf Müller, D. C. Ayantika, Felix Ploeger, and Alexandru Rap
Atmos. Chem. Phys., 17, 1297–1311, https://doi.org/10.5194/acp-17-1297-2017, https://doi.org/10.5194/acp-17-1297-2017, 2017
Short summary
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In the monsoon season, Asian NOx emissions are rapidly transported to the UTLS and can impact ozone in the UTLS. From chemistry–climate model simulations, we show that increasing Asian NOx emissions have enhanced ozone radiative forcing over Southeast Asia, which leads to significant warming over the Tibetan Plateau and increase precipitation over India. However, a further increase in NOx emissions elicited negative precipitation due to reversal of monsoon Hadley circulation.
S. Fadnavis, K. Semeniuk, M. G. Schultz, M. Kiefer, A. Mahajan, L. Pozzoli, and S. Sonbawane
Atmos. Chem. Phys., 15, 11477–11499, https://doi.org/10.5194/acp-15-11477-2015, https://doi.org/10.5194/acp-15-11477-2015, 2015
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The model and MIPAS satellite data show that there are three regions which contribute substantial pollution to the south Asian UTLS: the Asian summer monsoon (ASM), the North American monsoon (NAM) and the West African monsoon (WAM). However, penetration due to ASM convection reaches deeper into the UTLS compared to NAM and WAM outflow. Simulations show that westerly winds drive North American and European pollutants eastward where they can become part of the ASM and lifted to LS.
S. D. Bansod, S. Fadnavis, and S. P. Ghanekar
Ann. Geophys., 33, 1051–1058, https://doi.org/10.5194/angeo-33-1051-2015, https://doi.org/10.5194/angeo-33-1051-2015, 2015
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In this paper inter-annual variability of tropospheric air temperature over the Asian summer monsoon region during the pre-monsoon months is examined in relation to Indian summer monsoon rainfall (ISMR; June to September total rainfall). The results indicate a strong and significant northwest–southeast dipole structure in the spatial correlations over the Indian region with highly significant positive (negative) correlations over the regions of north India and the western Tibetan Plateau region.
S. Fadnavis, M. G. Schultz, K. Semeniuk, A. S. Mahajan, L. Pozzoli, S. Sonbawne, S. D. Ghude, M. Kiefer, and E. Eckert
Atmos. Chem. Phys., 14, 12725–12743, https://doi.org/10.5194/acp-14-12725-2014, https://doi.org/10.5194/acp-14-12725-2014, 2014
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The Asian summer monsoon transports pollutants from local emission sources to the upper troposphere and lower stratosphere (UTLS). The increasing trend of these pollutants may have climatic impact. This study addresses the impact of convectively lifted Indian and Chinese emissions on the ULTS. Sensitivity experiments with emission changes in particular regions show that Chinese emissions have a greater impact on the concentrations of NOY species than Indian emissions.
S. Fadnavis, K. Semeniuk, M. G. Schultz, A. Mahajan, L. Pozzoli, S. Sonbawane, and M. Kiefer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-20159-2014, https://doi.org/10.5194/acpd-14-20159-2014, 2014
Revised manuscript not accepted
S. Fadnavis, K. Semeniuk, L. Pozzoli, M. G. Schultz, S. D. Ghude, S. Das, and R. Kakatkar
Atmos. Chem. Phys., 13, 8771–8786, https://doi.org/10.5194/acp-13-8771-2013, https://doi.org/10.5194/acp-13-8771-2013, 2013
Mahalakshmi Venkata Dangeti, Mahesh Pathakoti, Kanchana Lakshmi Asuri, Sujatha Peethani, Ibrahim Shaik, Rajan Krishnan Sundara, Vijay Kumar Sagar, Raja Pushpanathan, Yogesh Kumar Tiwari, and Prakash Chauhan
Atmos. Chem. Phys., 24, 12843–12859, https://doi.org/10.5194/acp-24-12843-2024, https://doi.org/10.5194/acp-24-12843-2024, 2024
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The present study investigated the space–time variability of XCH4 over coal fields, power plants, and wetlands using long-term GOSAT and S5/TROPOMI data. The XCH4 variability associated with the heterogenous sources present in the south Asian (India) region and their implications for atmospheric XCH4 concentrations were evaluated. The CH4 concentrations were mapped against the emissions in the agro-climatic zones, and a statistically high correlation was found in the Indo-Gangetic Plain region.
Yasin Elshorbany, Jerald R. Ziemke, Sarah Strode, Hervé Petetin, Kazuyuki Miyazaki, Isabelle De Smedt, Kenneth Pickering, Rodrigo J. Seguel, Helen Worden, Tamara Emmerichs, Domenico Taraborrelli, Maria Cazorla, Suvarna Fadnavis, Rebecca R. Buchholz, Benjamin Gaubert, Néstor Y. Rojas, Thiago Nogueira, Thérèse Salameh, and Min Huang
Atmos. Chem. Phys., 24, 12225–12257, https://doi.org/10.5194/acp-24-12225-2024, https://doi.org/10.5194/acp-24-12225-2024, 2024
Short summary
Short summary
We investigated tropospheric ozone spatial variability and trends from 2005 to 2019 and related those to ozone precursors on global and regional scales. We also investigate the spatiotemporal characteristics of the ozone formation regime in relation to ozone chemical sources and sinks. Our analysis is based on remote sensing products of the tropospheric column of ozone and its precursors, nitrogen dioxide, formaldehyde, and total column CO, as well as ozonesonde data and model simulations.
Suvarna Fadnavis, Yasin Elshorbany, Jerald Ziemke, Brice Barret, Alexandru Rap, P. R. Satheesh Chandran, Richard Pope, Vijay Sagar, Domenico Taraborrelli, Eric Le Flochmoen, Juan Cuesta, Catherine Wespes, Folkert Boersma, Isolde Glissenaar, Isabelle De Smedt, Michel Van Roozendael, Hervé Petetin, and Isidora Anglou
EGUsphere, https://doi.org/10.5194/egusphere-2024-3050, https://doi.org/10.5194/egusphere-2024-3050, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Satellites and model simulations show enhancement in tropospheric ozone, which is highly impacted by human-produced Nitrous oxides compared to volatile organic compounds. The increased amount of ozone enhances ozone radiative forcing. The ozone enhancement and associated radiative forcing are highest over South and East Asia. The emissions of Nitrous oxides show a higher influence in shifting ozone photochemical regimes than volatile organic compounds.
Jan Clemens, Bärbel Vogel, Lars Hoffmann, Sabine Griessbach, Nicole Thomas, Suvarna Fadnavis, Rolf Müller, Thomas Peter, and Felix Ploeger
Atmos. Chem. Phys., 24, 763–787, https://doi.org/10.5194/acp-24-763-2024, https://doi.org/10.5194/acp-24-763-2024, 2024
Short summary
Short summary
The source regions of the Asian tropopause aerosol layer (ATAL) are debated. We use balloon-borne measurements of the layer above Nainital (India) in August 2016 and atmospheric transport models to find ATAL source regions. Most air originated from the Tibetan plateau. However, the measured ATAL was stronger when more air originated from the Indo-Gangetic Plain and weaker when more air originated from the Pacific. Hence, the results indicate important anthropogenic contributions to the ATAL.
Suvarna Fadnavis, Bernd Heinold, T. P. Sabin, Anne Kubin, Katty Huang, Alexandru Rap, and Rolf Müller
Atmos. Chem. Phys., 23, 10439–10449, https://doi.org/10.5194/acp-23-10439-2023, https://doi.org/10.5194/acp-23-10439-2023, 2023
Short summary
Short summary
The influence of the COVID-19 lockdown on the Himalayas caused increases in snow cover and a decrease in runoff, ultimately leading to an enhanced snow water equivalent. Our findings highlight that, out of the two processes causing a retreat of Himalayan glaciers – (1) slow response to global climate change and (2) fast response to local air pollution – a policy action on the latter is more likely to be within the reach of possible policy action to help billions of people in southern Asia.
Suvarna Fadnavis, Prashant Chavan, Akash Joshi, Sunil M. Sonbawne, Asutosh Acharya, Panuganti C. S. Devara, Alexandru Rap, Felix Ploeger, and Rolf Müller
Atmos. Chem. Phys., 22, 7179–7191, https://doi.org/10.5194/acp-22-7179-2022, https://doi.org/10.5194/acp-22-7179-2022, 2022
Short summary
Short summary
We show that large amounts of anthropogenic aerosols are transported from South Asia to the northern Indian Ocean. These aerosols are then lifted into the UTLS by the ascending branch of the Hadley circulation. They are further transported to the Southern Hemisphere and downward via westerly ducts over the tropical Atlantic and Pacific. These aerosols increase tropospheric heating, resulting in an increase in water vapor, which is then transported to the UTLS.
Prashant Chavan, Suvarna Fadnavis, Tanusri Chakroborty, Christopher E. Sioris, Sabine Griessbach, and Rolf Müller
Atmos. Chem. Phys., 21, 14371–14384, https://doi.org/10.5194/acp-21-14371-2021, https://doi.org/10.5194/acp-21-14371-2021, 2021
Short summary
Short summary
Biomass burning (BB) over Asia is a strong source of carbonaceous aerosols during spring. Here, we show an outflow of Asian BB carbonaceous aerosols into the UTLS. These aerosols enhance atmospheric heating and produce circulation changes that lead to the enhancement of water vapor in the UTLS over the tropics. In the stratosphere, water vapor is further transported to the South Pole by the Brewer–Dobson circulation. Enhancement of water vapor in the UTLS has implications for climate change.
Jean-Philippe Putaud, Luca Pozzoli, Enrico Pisoni, Sebastiao Martins Dos Santos, Friedrich Lagler, Guido Lanzani, Umberto Dal Santo, and Augustin Colette
Atmos. Chem. Phys., 21, 7597–7609, https://doi.org/10.5194/acp-21-7597-2021, https://doi.org/10.5194/acp-21-7597-2021, 2021
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To determine the impact of the COVID lockdown on air quality in northern Italy, measurements of atmospheric pollutants (NO2, PM10, O3, NO, SO2 ) were compared to the output of a model ignoring the lockdown. We found that NO2 decreased on average by −30 % to −40 %. Unlike NO2, PM10 was not significantly affected due to the compensation of decreased emissions from traffic by increased emissions from domestic heating and/or by changes in atmospheric chemistry enhancing secondary aerosol formation.
Teresa Jorge, Simone Brunamonti, Yann Poltera, Frank G. Wienhold, Bei P. Luo, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, Susanne Körner, Ruud Dirksen, Manish Naja, Suvarna Fadnavis, and Thomas Peter
Atmos. Meas. Tech., 14, 239–268, https://doi.org/10.5194/amt-14-239-2021, https://doi.org/10.5194/amt-14-239-2021, 2021
Short summary
Short summary
Balloon-borne frost point hygrometers are crucial for the monitoring of water vapour in the upper troposphere and lower stratosphere. We found that when traversing a mixed-phase cloud with big supercooled droplets, the intake tube of the instrument collects on its inner surface a high percentage of these droplets. The newly formed ice layer will sublimate at higher levels and contaminate the measurement. The balloon is also a source of contamination, but only at higher levels during the ascent.
Sreeharsha Hanumanthu, Bärbel Vogel, Rolf Müller, Simone Brunamonti, Suvarna Fadnavis, Dan Li, Peter Ölsner, Manish Naja, Bhupendra Bahadur Singh, Kunchala Ravi Kumar, Sunil Sonbawne, Hannu Jauhiainen, Holger Vömel, Beiping Luo, Teresa Jorge, Frank G. Wienhold, Ruud Dirkson, and Thomas Peter
Atmos. Chem. Phys., 20, 14273–14302, https://doi.org/10.5194/acp-20-14273-2020, https://doi.org/10.5194/acp-20-14273-2020, 2020
Short summary
Short summary
During boreal summer, anthropogenic sources yield the Asian Tropopause Aerosol Layer (ATAL), found in Asia between about 13 and 18 km altitude. Balloon-borne measurements of the ATAL conducted in northern India in 2016 show the strong variability of the ATAL. To explain its observed variability, model simulations are performed to deduce the origin of air masses on the Earth's surface, which is important to develop recommendations for regulations of anthropogenic surface emissions of the ATAL.
Suvarna Fadnavis, Rolf Müller, Gayatry Kalita, Matthew Rowlinson, Alexandru Rap, Jui-Lin Frank Li, Blaž Gasparini, and Anton Laakso
Atmos. Chem. Phys., 19, 9989–10008, https://doi.org/10.5194/acp-19-9989-2019, https://doi.org/10.5194/acp-19-9989-2019, 2019
Short summary
Short summary
This paper highlights the impact of Asian anthropogenic emission changes in SO2 on sulfate loading in the Asian upper troposphere–lower stratosphere from a global chemistry–climate model and satellite remote sensing. Estimated seasonal mean direct radiative forcing at the top of the atmosphere induced by the increase in Indian SO2 is −0.2–−1.5 W m2 over India. Chinese SO2 emission reduction leads to a positive radiative forcing of ~0.6–6 W m2 over China. It will likely decrease Indian rainfall.
Simone Brunamonti, Teresa Jorge, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Singh, K. Ravi Kumar, Sunil Sonbawne, Susanne Meier, Deepak Singh, Frank G. Wienhold, Bei Ping Luo, Maxi Boettcher, Yann Poltera, Hannu Jauhiainen, Rijan Kayastha, Jagadishwor Karmacharya, Ruud Dirksen, Manish Naja, Markus Rex, Suvarna Fadnavis, and Thomas Peter
Atmos. Chem. Phys., 18, 15937–15957, https://doi.org/10.5194/acp-18-15937-2018, https://doi.org/10.5194/acp-18-15937-2018, 2018
Short summary
Short summary
Based on balloon-borne measurements performed in India and Nepal in 2016–2017, we infer the vertical distributions of water vapor, ozone and aerosols in the atmosphere, from the surface to 30 km altitude. Our measurements show that the atmospheric dynamics of the Asian summer monsoon system over the polluted Indian subcontinent lead to increased concentrations of water vapor and aerosols in the high atmosphere (approximately 14–20 km altitude), which can have an important effect on climate.
Suvarna Fadnavis, Chaitri Roy, Rajib Chattopadhyay, Christopher E. Sioris, Alexandru Rap, Rolf Müller, K. Ravi Kumar, and Raghavan Krishnan
Atmos. Chem. Phys., 18, 11493–11506, https://doi.org/10.5194/acp-18-11493-2018, https://doi.org/10.5194/acp-18-11493-2018, 2018
Short summary
Short summary
Rapid industrialization, traffic growth and urbanization resulted in a significant increase in the tropospheric trace gases over Asia. There is global concern about rising levels of these trace gases. The monsoon convection transports these gases to the upper-level-anticyclone. In this study, we show transport of these gases to the extratropics via eddy-shedding from the anticyclone. We also deliberate on changes in ozone heating rates due to the transport of Asian trace gases.
Xin Lin, Philippe Ciais, Philippe Bousquet, Michel Ramonet, Yi Yin, Yves Balkanski, Anne Cozic, Marc Delmotte, Nikolaos Evangeliou, Nuggehalli K. Indira, Robin Locatelli, Shushi Peng, Shilong Piao, Marielle Saunois, Panangady S. Swathi, Rong Wang, Camille Yver-Kwok, Yogesh K. Tiwari, and Lingxi Zhou
Atmos. Chem. Phys., 18, 9475–9497, https://doi.org/10.5194/acp-18-9475-2018, https://doi.org/10.5194/acp-18-9475-2018, 2018
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We simulate CH4 and CO2 using a zoomed global transport model with a horizontal resolution of ~50 km over South and East Asia, as well as a standard model version for comparison. Model performance is evaluated for both gases and versions at multiple timescales against a new collection of surface stations over this key GHG-emitting region. The evaluation at different timescales and comparisons between gases and model versions have implications for possible model improvements and inversions.
Luca Pozzoli, Srdan Dobricic, Simone Russo, and Elisabetta Vignati
Atmos. Chem. Phys., 17, 11803–11818, https://doi.org/10.5194/acp-17-11803-2017, https://doi.org/10.5194/acp-17-11803-2017, 2017
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We investigated how the changes in atmospheric circulation of the Northern Hemisphere in winter, due to sea-ice retreat and increasing temperatures in the Arctic, may have also impacted black carbon transport and deposition to the Arctic, which may further accelerate the snow and sea-ice melting. The anthropogenic emission reductions applied in the last decades in Europe and North America were, therefore, crucial to counterbalance the most likely trend of increasing pollution in the Arctic.
Suvarna Fadnavis, Gayatry Kalita, K. Ravi Kumar, Blaž Gasparini, and Jui-Lin Frank Li
Atmos. Chem. Phys., 17, 11637–11654, https://doi.org/10.5194/acp-17-11637-2017, https://doi.org/10.5194/acp-17-11637-2017, 2017
Short summary
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In this study, the model simulations show that monsoon convection over the Bay of Bengal, the South China Sea and southern flanks of the Himalayas transports Asian carbonaceous aerosol into the UTLS. Carbonaceous aerosol induces enhancement in heating rate, vertical velocity and water vapor transport in the UTLS. Doubling of carbonaceous aerosols creates an anomalous warming over the TP. It generates monsoon Hadley circulation and thus increases precipitation over India and northeast China.
Efisio Solazzo, Roberto Bianconi, Christian Hogrefe, Gabriele Curci, Paolo Tuccella, Ummugulsum Alyuz, Alessandra Balzarini, Rocío Baró, Roberto Bellasio, Johannes Bieser, Jørgen Brandt, Jesper H. Christensen, Augistin Colette, Xavier Francis, Andrea Fraser, Marta Garcia Vivanco, Pedro Jiménez-Guerrero, Ulas Im, Astrid Manders, Uarporn Nopmongcol, Nutthida Kitwiroon, Guido Pirovano, Luca Pozzoli, Marje Prank, Ranjeet S. Sokhi, Alper Unal, Greg Yarwood, and Stefano Galmarini
Atmos. Chem. Phys., 17, 3001–3054, https://doi.org/10.5194/acp-17-3001-2017, https://doi.org/10.5194/acp-17-3001-2017, 2017
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As part of the third phase of AQMEII, this study uses timescale analysis to apportion error to the responsible processes, detect causes of model error, and identify the processes and scales that require dedicated investigations. The analysis tackles model performance gauging through measurement-to-model comparison, error decomposition, and time series analysis of model biases for ozone, CO, SO2, NO, NO2, PM10, PM2.5, wind speed, and temperature over Europe and North America.
Chaitri Roy, Suvarna Fadnavis, Rolf Müller, D. C. Ayantika, Felix Ploeger, and Alexandru Rap
Atmos. Chem. Phys., 17, 1297–1311, https://doi.org/10.5194/acp-17-1297-2017, https://doi.org/10.5194/acp-17-1297-2017, 2017
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In the monsoon season, Asian NOx emissions are rapidly transported to the UTLS and can impact ozone in the UTLS. From chemistry–climate model simulations, we show that increasing Asian NOx emissions have enhanced ozone radiative forcing over Southeast Asia, which leads to significant warming over the Tibetan Plateau and increase precipitation over India. However, a further increase in NOx emissions elicited negative precipitation due to reversal of monsoon Hadley circulation.
Imran A. Girach, Narendra Ojha, Prabha R. Nair, Andrea Pozzer, Yogesh K. Tiwari, K. Ravi Kumar, and Jos Lelieveld
Atmos. Chem. Phys., 17, 257–275, https://doi.org/10.5194/acp-17-257-2017, https://doi.org/10.5194/acp-17-257-2017, 2017
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This study presents first ship-borne measurements of trace gases over the Bay of Bengal during summer monsoon. The observed variations in trace gases are shown to be due to dynamics/transport and en route photochemistry. Analysis of meteorological and chemical fields shows that significantly lower ozone during rainfall is associated with the downdrafts. A regional model reproduces the observed variations and revealed the rapid transport of ozone across the Bay of Bengal during an event.
S. Fadnavis, K. Semeniuk, M. G. Schultz, M. Kiefer, A. Mahajan, L. Pozzoli, and S. Sonbawane
Atmos. Chem. Phys., 15, 11477–11499, https://doi.org/10.5194/acp-15-11477-2015, https://doi.org/10.5194/acp-15-11477-2015, 2015
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The model and MIPAS satellite data show that there are three regions which contribute substantial pollution to the south Asian UTLS: the Asian summer monsoon (ASM), the North American monsoon (NAM) and the West African monsoon (WAM). However, penetration due to ASM convection reaches deeper into the UTLS compared to NAM and WAM outflow. Simulations show that westerly winds drive North American and European pollutants eastward where they can become part of the ASM and lifted to LS.
S. D. Bansod, S. Fadnavis, and S. P. Ghanekar
Ann. Geophys., 33, 1051–1058, https://doi.org/10.5194/angeo-33-1051-2015, https://doi.org/10.5194/angeo-33-1051-2015, 2015
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In this paper inter-annual variability of tropospheric air temperature over the Asian summer monsoon region during the pre-monsoon months is examined in relation to Indian summer monsoon rainfall (ISMR; June to September total rainfall). The results indicate a strong and significant northwest–southeast dipole structure in the spatial correlations over the Indian region with highly significant positive (negative) correlations over the regions of north India and the western Tibetan Plateau region.
G. Baldassarre, L. Pozzoli, C. C. Schmidt, A. Unal, T. Kindap, W. P. Menzel, S. Whitburn, P.-F. Coheur, A. Kavgaci, and J. W. Kaiser
Atmos. Chem. Phys., 15, 8539–8558, https://doi.org/10.5194/acp-15-8539-2015, https://doi.org/10.5194/acp-15-8539-2015, 2015
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We investigate the quality of fire emission estimates derived from SEVIRI FRP for air quality simulations with the Community Multiscale Air Quality (CMAQ) model, by comparing them with available MODIS FRP-based ones.
We demonstrate that geostationary observations allow for refining biomass burning emissions, which can subsequently be used in regional scale air quality models in order to improve the prediction of chemical composition of the atmosphere in presence of large fire episodes.
X. Pan, M. Chin, R. Gautam, H. Bian, D. Kim, P. R. Colarco, T. L. Diehl, T. Takemura, L. Pozzoli, K. Tsigaridis, S. Bauer, and N. Bellouin
Atmos. Chem. Phys., 15, 5903–5928, https://doi.org/10.5194/acp-15-5903-2015, https://doi.org/10.5194/acp-15-5903-2015, 2015
S. Fadnavis, M. G. Schultz, K. Semeniuk, A. S. Mahajan, L. Pozzoli, S. Sonbawne, S. D. Ghude, M. Kiefer, and E. Eckert
Atmos. Chem. Phys., 14, 12725–12743, https://doi.org/10.5194/acp-14-12725-2014, https://doi.org/10.5194/acp-14-12725-2014, 2014
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The Asian summer monsoon transports pollutants from local emission sources to the upper troposphere and lower stratosphere (UTLS). The increasing trend of these pollutants may have climatic impact. This study addresses the impact of convectively lifted Indian and Chinese emissions on the ULTS. Sensitivity experiments with emission changes in particular regions show that Chinese emissions have a greater impact on the concentrations of NOY species than Indian emissions.
K. Tsigaridis, N. Daskalakis, M. Kanakidou, P. J. Adams, P. Artaxo, R. Bahadur, Y. Balkanski, S. E. Bauer, N. Bellouin, A. Benedetti, T. Bergman, T. K. Berntsen, J. P. Beukes, H. Bian, K. S. Carslaw, M. Chin, G. Curci, T. Diehl, R. C. Easter, S. J. Ghan, S. L. Gong, A. Hodzic, C. R. Hoyle, T. Iversen, S. Jathar, J. L. Jimenez, J. W. Kaiser, A. Kirkevåg, D. Koch, H. Kokkola, Y. H Lee, G. Lin, X. Liu, G. Luo, X. Ma, G. W. Mann, N. Mihalopoulos, J.-J. Morcrette, J.-F. Müller, G. Myhre, S. Myriokefalitakis, N. L. Ng, D. O'Donnell, J. E. Penner, L. Pozzoli, K. J. Pringle, L. M. Russell, M. Schulz, J. Sciare, Ø. Seland, D. T. Shindell, S. Sillman, R. B. Skeie, D. Spracklen, T. Stavrakou, S. D. Steenrod, T. Takemura, P. Tiitta, S. Tilmes, H. Tost, T. van Noije, P. G. van Zyl, K. von Salzen, F. Yu, Z. Wang, Z. Wang, R. A. Zaveri, H. Zhang, K. Zhang, Q. Zhang, and X. Zhang
Atmos. Chem. Phys., 14, 10845–10895, https://doi.org/10.5194/acp-14-10845-2014, https://doi.org/10.5194/acp-14-10845-2014, 2014
S. Fadnavis, K. Semeniuk, M. G. Schultz, A. Mahajan, L. Pozzoli, S. Sonbawane, and M. Kiefer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-20159-2014, https://doi.org/10.5194/acpd-14-20159-2014, 2014
Revised manuscript not accepted
S. Fadnavis, K. Semeniuk, L. Pozzoli, M. G. Schultz, S. D. Ghude, S. Das, and R. Kakatkar
Atmos. Chem. Phys., 13, 8771–8786, https://doi.org/10.5194/acp-13-8771-2013, https://doi.org/10.5194/acp-13-8771-2013, 2013
Short summary
Analysis of 10 years (2000–2009) of Carbon Tracker (CT-2010) model CO2 fluxes gives insights into the regional variation of CO2 fluxes over the Indian land mass. CO2 emission hot spots overlap with locations of densely clustered thermal power plants, coal mines, and other industrial and urban centres. CO2 sink regions coincide with locations of dense forests with less industrial centres. CO2 fossil fuel emissions show good agreement with two bottom-up inventories REAS v1.11 and EDGAR v4.2.
Analysis of 10 years (2000–2009) of Carbon Tracker (CT-2010) model CO2 fluxes gives insights...