The relationship between aerosol optical depth and synoptic weather systems over East Asia
Abstract
The rapid economic development in China has caused severe air pollution in both local and downwind regions. The focus of this study is to investigate the relationship between aerosol spatial-temporal variability and synoptic weather types using long-term remote sensing and reanalysis data. We apply Empirical Orthogonal Function (EOF) analysis on MODerate-resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) retrievals from January 2005 to December 2015 over East Asia. The daily synoptic weather pattern is identified using objective machine learning algorithm based on reanalysis data and surface weather stations over Taiwan. We found synoptic weather events are the dominate factors to affect the AOD variations in East Asia in each season. In springtime, the first EOF of AOD demonstrates the maximum anomalies over Southeast Asia, which is coherent the enhanced low-level southwesterly. While in summertime, the maximum anomalies of first EOF occur over North China Plain, which is highly associated with the number of fronts near Taiwan. The correlation maps between the leading principal components and meteorological variables, such as wind, stability, precipitation, relative humidity, reveal that the environmental conditions are well-connected with the seasonal AOD variability. These results suggest AOD variation in East Asia may change along with future changes of large-scale circulations under global warming scenarios.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A44A..06C
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0317 Chemical kinetic and photochemical properties;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES