Effects of the Largest Lake of the Tibetan Plateau on the Regional Climate. Issue 22 (21st November 2020)

• Record Type: Journal Article
• Authors: Su, Dongsheng; Wen, Lijuan; Gao, Xiaoqing; Leppäranta, Matti; Song, Xingyu; Shi, Qianqian; Kirillin, Georgiy
• Is Part Of: Journal of geophysical research. Volume 125:Issue 22(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-11-21
• Subjects: Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2020JD033396
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: Qinghai Lake is the largest lake in China. However, its influence on the local climate remains poorly understood. By using an atmosphere‐lake coupled model, we investigated the impact of the lake on the local climate. After the adjustment of four key parameters, the model reasonably reproduced the lake‐air interaction. Superimposed by the orographic effects on lake‐land breeze circulation, the presence of the lake enhanced precipitation over the southern part of the lake and its adjacent land, while slightly reduced precipitation along the northern shore of the lake. The lake effect on local precipitation revealed a distinct seasonal and diurnal variability, reducing precipitation in May (−6.6%) and June (−4.5%) and increasing it from July (5.7%) to November (125.6%). During the open water season, the lake's daytime cooling effect weakened and the nighttime warming effect strengthened, affecting spatial distribution and intensity of lake‐induced precipitation. In early summer, precipitation slightly decreased over the north part of the lake due to the lake's daytime cooling. In turn, lake‐induced nighttime warming increased precipitation over the southern section of the lake and its adjacent land. With the start of the autumn cooling in September, heat and moisture fluxes from the lake resulted in precipitation increase in both daytime and nighttime over the entire lake. In October, the background atmospheric circulation coupled with the strong lake effects lead to a small amount but high proportion of lake‐induced precipitation spreading evenly over the lake. Key Points: The coupled lake‐atmosphere model after adjusting four key parameters performs well in quantifying the lake's regional climate effects Qinghai Lake decreased the local precipitation during April–June while increased that during July–November Throughout the simulation period, precipitation declined slightly in the north and rose greatly in the south due to the lake's presence