Climate and Dynamics
A spatial analysis of pan evaporation trends in China, 1955–2000
Article first published online: 7 AUG 2004
Copyright 2004 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 109, Issue D15, 16 August 2004
How to Cite
2004), A spatial analysis of pan evaporation trends in China, 1955–2000, J. Geophys. Res., 109, D15102, doi:10.1029/2004JD004511., , , and (
- Issue published online: 7 AUG 2004
- Article first published online: 7 AUG 2004
- Manuscript Accepted: 15 MAR 2004
- Manuscript Revised: 2 MAR 2004
- Manuscript Received: 4 JAN 2004
- pan evaporation;
 Pan evaporation, an indicator of potential evaporation, has decreased during the last several decades in many parts of the world. This trend is contrary to the expectation that global warming will be accompanied by an increase in terrestrial evaporation, known as the pan evaporation paradox. In this paper we present an analysis of changes in the spatial patterns of pan evaporation in China based on data from 85 weather stations from 1955 to 2000. We found that pan evaporation decreased in China from 1955 to 2000. The decrease was statistically significant in all of China's eight climatic regions except northeast China. We also found that the decrease in solar irradiance was most likely the driving force for the reduced pan evaporation in China. However, unlike in other areas of the world, in China the decrease in solar irradiance was not always accompanied by an increase in cloud cover and precipitation. Therefore we speculate that aerosols may play a critical role in the decrease of solar irradiance in China. By subdividing China into eight climatic regions, we found that the rate of decrease in pan evaporation was highest in the northwest and lowest in the southwest. Although changes in solar irradiance are the main cause of decreasing pan evaporation, water conditions influence the sensitivity of pan evaporation to the change in solar irradiance in comparing the eight climatic regions. Thus the spatial trends of pan evaporation differ from those of solar irradiance among these regions.