气候变化领域集成服务门户(CCPortal): Heat Storage Effect on Evaporation Estimates of China's Largest Freshwater Lake

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DOI	10.1029/2019JD032334
	Heat Storage Effect on Evaporation Estimates of China's Largest Freshwater Lake
	Gan G.; Liu Y.
发表日期	2020
ISSN	2169897X
卷号	125 期号:19
英文摘要	Evaporation of water bodies is significantly controlled by the available energy (net radiation Rn minus heat storage G). Compared to deep lakes or lakes in the high-latitude or high-altitude regions, the heat storage effects of shallow lakes in subtropical regions are less well studied. In this paper, we tested the heat storage effect on the latent heat fluxes estimation using the Priestley-Taylor (PT) equation and numerical water temperature simulations in an ephemeral and shallow lake, Poyang Lake, in China. Results showed that the estimation bias was significantly correlated with heat storage changes (r = 0.97). Overlooking the impacts of the heat storage changes will induce an increase in the RMSE (root-mean-square error) of the evaporation estimation from 10.1 to 54.4 W m−2. Evaporation was overestimated in June and underestimated in August because the daytime Rn tended to be stored in water in June, whereas the heat storage during daytime tended to be released as nighttime evaporation in August, when the vapor gradient between the saturated surface and the air was generally larger than in other months. Water temperature simulations showed that the diurnal changes in the heat storage in the layer that were less than 2 m deep govern G of the total water column. PT estimation of a shallow lake can be improved if the temperature of the top 2 m of water is known. Also, from the modeling perspective, because G was linearly correlated with Rn (r = 0.77), a simple equation (a*Rn + b) that approximates the available energy can improve the evaporation estimate. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	heat storage; nighttime evaporation; Priestley-Taylor equation; water temperature simulation
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185730
作者单位	Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; Key Laboratory of Watershed Geographic Sciences, Chinese Academy of Sciences, Nanjing, China
推荐引用方式 GB/T 7714	Gan G.,Liu Y.. Heat Storage Effect on Evaporation Estimates of China's Largest Freshwater Lake[J],2020,125(19).
APA	Gan G.,&Liu Y..(2020).Heat Storage Effect on Evaporation Estimates of China's Largest Freshwater Lake.Journal of Geophysical Research: Atmospheres,125(19).
MLA	Gan G.,et al."Heat Storage Effect on Evaporation Estimates of China's Largest Freshwater Lake".Journal of Geophysical Research: Atmospheres 125.19(2020).