Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas
The Himalayas and the Tibetan Plateau region (HTP), despite being a remote and sparsely populated area, is regularly exposed to polluted air masses with significant amounts of aerosols including black carbon. These dark, light-absorbing particles are known to exert a great melting potential...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2015-06-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | http://www.atmos-chem-phys.net/15/6007/2015/acp-15-6007-2015.pdf |
| _version_ | 1818557715768672256 |
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| author | Z. L. Lüthi B. Škerlak S.-W. Kim A. Lauer A. Mues M. Rupakheti S. Kang |
| author_facet | Z. L. Lüthi B. Škerlak S.-W. Kim A. Lauer A. Mues M. Rupakheti S. Kang |
| author_sort | Z. L. Lüthi |
| collection | DOAJ |
| description | The Himalayas and the Tibetan Plateau region (HTP), despite being
a remote and sparsely populated area, is regularly exposed to
polluted air masses with significant amounts of aerosols including
black carbon. These dark, light-absorbing particles are known to
exert a great melting potential on mountain cryospheric reservoirs
through albedo reduction and radiative forcing. This study combines
ground-based and satellite remote sensing data to identify
a severe aerosol pollution episode observed simultaneously in
central Tibet and on the southern side of the Himalayas during
13–19 March 2009 (pre-monsoon). Trajectory calculations based on the
high-resolution numerical weather prediction model COSMO are used to
locate the source regions and study the mechanisms of pollution transport
in the complex topography of the HTP. We detail how polluted air masses
from an atmospheric brown cloud (ABC) over South Asia reach the
Tibetan Plateau within a few days. Lifting and advection of polluted air
masses over the great mountain range is enabled by a combination of
synoptic-scale and local meteorological processes. During the days prior
to the event, winds over the Indo-Gangetic Plain (IGP) are generally weak
at lower levels, allowing for accumulation of pollutants and thus the
formation of ABCs. The subsequent passing of synoptic-scale troughs leads
to southwesterly flow in the middle troposphere over northern and central
India, carrying the polluted air masses across the Himalayas. As the IGP is
known to be a hotspot of ABCs, the cross-Himalayan transport of polluted air
masses may have serious implications for the cryosphere in the HTP
and impact climate on regional to global scales. Since the current
study focuses on one particularly strong pollution episode, quantifying
the frequency and magnitude of similar events in a climatological study
is required to assess the total impact. |
| first_indexed | 2024-12-14T00:03:12Z |
| format | Article |
| id | doaj.art-45d695ffb29944c7ad1f123f2c6c1caf |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-12-14T00:03:12Z |
| publishDate | 2015-06-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-45d695ffb29944c7ad1f123f2c6c1caf2022-12-21T23:26:12ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242015-06-0115116007602110.5194/acp-15-6007-2015Atmospheric brown clouds reach the Tibetan Plateau by crossing the HimalayasZ. L. Lüthi0B. Škerlak1S.-W. Kim2A. Lauer3A. Mues4M. Rupakheti5S. Kang6Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research and CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences (CAS), Beijing, ChinaETH Zurich, Institute for Atmospheric and Climate Science, Zürich, SwitzerlandSchool of Earth and Environmental Sciences, Seoul National University, Seoul, Republic of KoreaIASS Institute for Advanced Sustainability Studies, Potsdam, GermanyIASS Institute for Advanced Sustainability Studies, Potsdam, GermanyIASS Institute for Advanced Sustainability Studies, Potsdam, GermanyKey Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research and CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences (CAS), Beijing, ChinaThe Himalayas and the Tibetan Plateau region (HTP), despite being a remote and sparsely populated area, is regularly exposed to polluted air masses with significant amounts of aerosols including black carbon. These dark, light-absorbing particles are known to exert a great melting potential on mountain cryospheric reservoirs through albedo reduction and radiative forcing. This study combines ground-based and satellite remote sensing data to identify a severe aerosol pollution episode observed simultaneously in central Tibet and on the southern side of the Himalayas during 13–19 March 2009 (pre-monsoon). Trajectory calculations based on the high-resolution numerical weather prediction model COSMO are used to locate the source regions and study the mechanisms of pollution transport in the complex topography of the HTP. We detail how polluted air masses from an atmospheric brown cloud (ABC) over South Asia reach the Tibetan Plateau within a few days. Lifting and advection of polluted air masses over the great mountain range is enabled by a combination of synoptic-scale and local meteorological processes. During the days prior to the event, winds over the Indo-Gangetic Plain (IGP) are generally weak at lower levels, allowing for accumulation of pollutants and thus the formation of ABCs. The subsequent passing of synoptic-scale troughs leads to southwesterly flow in the middle troposphere over northern and central India, carrying the polluted air masses across the Himalayas. As the IGP is known to be a hotspot of ABCs, the cross-Himalayan transport of polluted air masses may have serious implications for the cryosphere in the HTP and impact climate on regional to global scales. Since the current study focuses on one particularly strong pollution episode, quantifying the frequency and magnitude of similar events in a climatological study is required to assess the total impact.http://www.atmos-chem-phys.net/15/6007/2015/acp-15-6007-2015.pdf |
| spellingShingle | Z. L. Lüthi B. Škerlak S.-W. Kim A. Lauer A. Mues M. Rupakheti S. Kang Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas Atmospheric Chemistry and Physics |
| title | Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas |
| title_full | Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas |
| title_fullStr | Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas |
| title_full_unstemmed | Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas |
| title_short | Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas |
| title_sort | atmospheric brown clouds reach the tibetan plateau by crossing the himalayas |
| url | http://www.atmos-chem-phys.net/15/6007/2015/acp-15-6007-2015.pdf |
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