Potential Effects of Increasing Aerosols on Solar Radiation, Atmospheric Stability and Precipitation in China
Abstract
China has maintained a relatively long and complete historical climate records for detecting and attributing climate trends. Previous analyses of surface measurements including solar radiation, sunshine duration, cloud cover, and pan evaporation, showed a decreasing trend in the surface solar radiation, despite a concurrent tendency for more frequent clear sky in the last 50 years. More recent analysis further revealed that much of China has experienced significant decrease in global solar radiation and increase in diffuse solar radiation under cloud-free skies from 1960s to 1990s. These trends are consistent with the increasing aerosol loading from emission of pollutants in China. To further our understanding of aerosol effects, analyses are being performed to investigate observed changes in precipitation characteristics and atmospheric stability. Analysis of long-term precipitation data shows that the frequency and amount of light rain have decreased in the second half of the last century, especially over eastern China where air pollution and aerosol loading are more pronounced. Furthermore, a weekend effect (more/less frequent precipitation during weekend/weekdays), consistent with the weekly cycle of the Air Pollution Index and concentrations of PM, SO2, and NOx, is evident in the daily precipitation record. Trends in atmospheric stability based on temperature sounding data from 1958-2004 are also being analyzed to elucidate possible links between the observed changes in solar radiation, atmospheric stability, precipitation characteristics, and potential indirect effects of increasing aerosol concentrations resulting from the ever- growing population and human activities in China.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2006
- Bibcode:
- 2006AGUFM.A11D..05Q
- Keywords:
-
- 0305 Aerosols and particles (0345;
- 4801;
- 4906);
- 0321 Cloud/radiation interaction;
- 0345 Pollution: urban and regional (0305;
- 0478;
- 4251)