Nine-year spatial and temporal evolution of desert dust aerosols over South and East Asia as revealed by CALIOP
We present a 3-D climatology of the desert dust distribution over South and East Asia derived using CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) data. To distinguish desert dust from total aerosol load we apply a methodology developed in the framework of EARLINET (...
| Main Authors: | , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2018-02-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/18/1337/2018/acp-18-1337-2018.pdf |
| Summary: | We present a 3-D climatology of the desert dust distribution over
South and East Asia derived using CALIPSO (Cloud-Aerosol Lidar and
Infrared Pathfinder Satellite Observation) data. To distinguish
desert dust from total aerosol load we apply a methodology developed
in the framework of EARLINET (European Aerosol Research Lidar
Network). The method involves the use of the particle linear
depolarization ratio and updated lidar ratio values suitable for
Asian dust, applied to multiyear CALIPSO observations
(January 2007–December 2015). The resulting dust product provides information
on the horizontal and vertical distribution of dust aerosols over
South and East Asia along with the seasonal transition of dust
transport pathways. Persistent high D_AOD (dust aerosol optical depth) values at 532 nm, of the order of 0.6, are present
over the arid and semi-arid desert regions. Dust aerosol transport
(range, height and intensity) is subject to high seasonality, with the highest values observed during spring for northern China
(Taklimakan and Gobi deserts) and during summer over the Indian
subcontinent (Thar Desert). Additionally, we decompose the CALIPSO
AOD (aerosol optical depth) into dust and non-dust aerosol
components to reveal the non-dust AOD over the highly industrialized
and densely populated regions of South and East Asia, where the
non-dust aerosols yield AOD values of the order of 0.5. Furthermore,
the CALIPSO-based short-term AOD and D_AOD time series and trends
between January 2007 and December 2015 are calculated over South and East Asia
and over selected subregions. Positive trends are observed over
northwest and east China and the Indian subcontinent, whereas over
southeast China trends are mostly negative. The calculated AOD
trends agree well with the trends derived from Aqua MODIS (Moderate
Resolution Imaging Spectroradiometer), although significant
differences are observed over specific regions. |
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| ISSN: | 1680-7316 1680-7324 |