Decreasing relative humidity dominates a reversal of decreasing pan evaporation in mainland China after 1989

Jin，Yubin1,2; Wang，Dashan1; Feng，Yu1,3; Wu，Jie1,4; Cui，Wenhui1; He，Xinyue1,5; Chen，Aifang1; Zeng，Zhenzhong1

2022-05-01

10.1016/j.jhydrol.2022.127641

JOURNAL OF HYDROLOGY   影响因子和分区

0022-1694

1879-2707

Pan evaporation (E) reflects the evaporation potential of surface water and is a key indicator of atmospheric evaporative demand. Previous studies have found a substantial decrease in E across China, dominated by declining wind speed and solar radiation before the late 2000 s. However, how E responds to the recovery of wind speed and solar radiation since the late 2000 s remains unclear. Here, we investigate the spatial and temporal patterns of E and analyze its controlling factors, based on the daily meteorological observations during 1965–2018 at 2,018 stations over China. We find that the annual E in the northwest and south of China is higher than that in the northeast and central parts of China. The national mean E decreases significantly during 1965–1989 at a rate of −6.57 mm yr, then reverses at a rate of 4.58 mm yr. Distinct seasonal discrepancies and geographical heterogeneities in E trends are observed. Declining wind speed mainly contributes to the decrease in E before 1989, while relative humidity is shown as the dominant factor that drives the growth of E after the turning point. The recovery of wind speed still has significant impact on E variation in parts of China, while E is only mainly affected by solar radiation in parts of central China in autumn. Our findings highlight the importance of understanding E variations and driving factors, and call for precautions and adaptation actions to combat and prevent flash droughts over China, especially in the south of China.

Atmospheric evaporative demand Pan evaporation Relative humidity Reversal Wind speed

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China[42071022,42001321] ; Southern University of Science and Technology[29/Y01296122]

Engineering ; Geology ; Water Resources

Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources

WOS:000790503300003

ELSEVIER

20221011742082

Atmospheric humidity ; Solar radiation ; Speed ; Surface waters ; Wind

Atmospheric Properties:443.1 ; Surface Water:444.1 ; Solar Energy and Phenomena:657.1 ; Chemical Operations:802.3

ENGINEERING

2-s2.0-85125545434

Scopus

1.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,China
2.School of Hydrology and Water Resources,Nanjing University of Information Science and Technology,Nanjing,China
3.Department of Civil Engineering,The University of Hong Kong,Hong Kong,Hong Kong
4.Department of Geoscience and Natural Resource Management,University of Copenhagen,Copenhagen,Denmark
5.School of Earth and Environment,University of Leeds,Leeds,United Kingdom

Jin，Yubin,Wang，Dashan,Feng，Yu,et al. Decreasing relative humidity dominates a reversal of decreasing pan evaporation in mainland China after 1989[J]. JOURNAL OF HYDROLOGY,2022,608.

Jin，Yubin.,Wang，Dashan.,Feng，Yu.,Wu，Jie.,Cui，Wenhui.,...&Zeng，Zhenzhong.(2022).Decreasing relative humidity dominates a reversal of decreasing pan evaporation in mainland China after 1989.JOURNAL OF HYDROLOGY,608.

Jin，Yubin,et al."Decreasing relative humidity dominates a reversal of decreasing pan evaporation in mainland China after 1989".JOURNAL OF HYDROLOGY 608(2022).