Title: |
Air pollution is pushing wind speed into a regulator of surface solar irradiance in China |
Author: |
Y W Wang, Y H Yang, X Y Zhou, N Zhao and J H Zhang |
PubYear: |
2014 |
Publication Name: |
Environmental Research Letters |
Volume、Issue、Page Number: |
;
9(5): 054004;
|
Impact Factor: |
|
Abstract: |
Analysis in 27 cities across China shows that surface solar irradiance (SSI) and wind speed track similar decadal trends in 1961–2011, suggesting wind speed as a possible regulator of SSI. This assumption is further confirmed by the continuously widening gap in annually averaged daily SSI between windy and windless clear-sky days with worsening air pollution. Wider gaps are noted for more polluted cities and seasons. The gap in SSI between windy and windless conditions could therefore serve as a good indicator for air quality. The regulatory effect of wind speed on SSI starts to be important when air pollution index exceeds the boundary of 125. A plausible mechanism of wind speed regulating SSI through interactions with aerosols is proposed. There are two cut-off points of 2.5 m s?1 and 3.5 m s?1 wind speeds. Winds <2.5 m s?1 noticeably disperse air pollutants and thereby enhance SSI. Above the 2.5 m s?1 threshold, air pollution and SSI become largely insensitive to changing wind speeds. Winds in excess of 3.5 m s?1 could enhance aerosol concentration probably by inducing dust-storms, which in turn attenuate SSI. |
DOI: |
http://dx.doi.org/10.1088/1748-9326/9/5/054004 |
Download: |
|