Impacts of urban expansion and future green planting on summer precipitation in the Beijing metropolitan area

作者：Chao Lin Zhang, Fei Chen, Shiguang Miao, Qing Chun Li, Xiangao Xia, Chunyi Xuan · 发表于：Journal of Geophysical Research Atmospheres · 年份：2009 · DOI：10.1029/2008jd010328 · 被引用次数：231 · 研究领域：Urban Heat Island Mitigation、Climate variability and models、Land Use and Ecosystem Services

In this study, an analysis of long‐term rainfall data reveals that the rapid urban expansion in Beijing since 1981 is statistically correlated to summer rainfall reduction in the northeast areas of Beijing from 1981 to 2005. This coincides with the period in which the shortage of water in the Beijing area has become a serious factor for sustainable economic development. Meanwhile, an analysis of the aerosol optical depth (AOD) from the Total Ozone Mapping Spectrometer spanning the years from 1980 to 2001 shows that there is no clear secular trend in summer AOD in Beijing. With the particular purpose of further understanding the effects of urban expansion on summer rainfall and the potential measures to mitigate such effects, a mesoscale weather/land‐surface/urban–coupled model along with different urban land‐use change scenarios are used to conduct numerical simulations for two selected heavy summer rainfall events with different, but representative, summer weather patterns in Beijing. Results show that urban expansion can produce less evaporation, higher surface temperatures, larger sensible heat fluxes, and a deeper boundary layer. This leads to less water vapor, more mixing of water vapor in the boundary layer, and hence less (more) convective available potential energy (convective inhibition energy). The combination of these factors induced by expanding urban surfaces is helpful in reducing precipitation for the Beijing area in general and, in particular, for the Miyun re...