气候变化领域集成服务门户(CCPortal): Suppressed Daytime Convection Over the Amazon River

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DOI	10.1029/2020JD033627
	Suppressed Daytime Convection Over the Amazon River
	Wu M.; Lee J.-E.; Wang D.; Salameh M.
发表日期	2021
ISSN	2169-897X
卷号	126 期号:13
英文摘要	We investigated the interaction between surface conditions and precipitating convection by comparing the Amazon River against the surrounding forest. Despite similar synoptic conditions within a few tens of kilometers, the river surface is substantially cooler than the surrounding forest during the day and warmer at night. We analyzed 20 years of high-resolution satellite precipitation data and confirmed previous findings of daytime rainfall reduction over the river for the whole Amazon Basin. The percentage reduction is strongest during the dry-to-wet transition season. In addition, the percentage reduction of individual tributary is significantly correlated with the Laplacian of surface temperature, which causes thermally driven surface divergence and suppresses local convection. Additionally, nighttime rainfall is enhanced over tributaries near the Atlantic coast during the wet season. A regional climate model then simulates the local rainfall anomalies associated with the river. Above the river, moisture diverges near the surface and converges above the surface before the daytime rainfall, partially driven by the horizontal gradient of humidity. Unlike the river, moisture convergence within the boundary layer is more critical for the rainfall above the forest region. Our studies suggest that strong thermal contrast can be important in deriving heterogeneous convection in moist tropical regions. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	Amazon River; atmospheric convection; precipitation; regional climate model; satellite remote sensing
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/237139
作者单位	Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States; Institute at Brown for Environment and Society, Brown University, Providence, RI, United States; Department of Environmental and Climate Sciences, Brookhaven National Laboratory, Upton, NY, United States
推荐引用方式 GB/T 7714	Wu M.,Lee J.-E.,Wang D.,et al. Suppressed Daytime Convection Over the Amazon River[J],2021,126(13).
APA	Wu M.,Lee J.-E.,Wang D.,&Salameh M..(2021).Suppressed Daytime Convection Over the Amazon River.Journal of Geophysical Research: Atmospheres,126(13).
MLA	Wu M.,et al."Suppressed Daytime Convection Over the Amazon River".Journal of Geophysical Research: Atmospheres 126.13(2021).