气候变化领域集成服务门户(CCPortal): The impact of snow loss and soil moisture on convective precipitation over the Rocky Mountains under climate warming

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DOI	10.1007/s00382-020-05622-7
	The impact of snow loss and soil moisture on convective precipitation over the Rocky Mountains under climate warming
	Wallace B.; Minder J.R.
发表日期	2021
ISSN	0930-7575
起始页码	1357
卷号	56 期号:2021-09-10
英文摘要	Warm season moist diurnal convection can be particularly sensitive to changes in land surface characteristics such as snow cover and soil moisture. Over regions of mountainous terrain, climate change is expected to reduce snow cover along the low-elevation seasonal snowpack margin. These snow reductions alter surface albedo and soil moisture content, leading to changes in surface fluxes and alterations in mesoscale orographic circulations that act to transport moisture and provide ascent. A set of convection-permitting regional climate simulations centered on the Rocky Mountains of Colorado are conducted from April through July across a period of 12 years (2002–2013). These include a reanalysis forced control run (CTR), a pseudo global warming run (PGW), and an additional altered land surface run (DSURF) used to isolate the effects of the snow albedo and soil moisture changes on orographic convection. Over the mountains, daytime hourly precipitation accumulation (0900–1800 MST) decreased in PGW by an average of 4.2% while precipitation in DSURF increased by 12.5%. On days with weak synoptic forcing, the PGW response more closely follow the DSURF response with daytime hourly increases averaging 29.7% for PGW and 28.7% for DSURF. For PGW, hourly daytime precipitation intensity increases of up to 82% overcome reductions in precipitation frequency to produce higher accumulations. DSURF shows smaller increases in intensity of up to 23% and broad increases in daytime frequency indicating that surface changes act to moderate reductions in the frequency of convective precipitation. Reduced snow cover contributes to this convective response by increasing convective instability and boundary layer moisture and decreasing lifting condensation level over the high terrain. Alterations in orographic thermal circulations contribute to this response by converging moisture over the high terrain and enhancing mesoscale ascent. © 2021, The Author(s).
英文关键词	Convection permitting modeling; Land surface-atmosphere interactions; Orographic convection; Regional climate
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/183293
作者单位	Department of Atmospheric and Environmental Sciences, State University of New York, University at Albany, Earth Sciences Bldg., 1400 Washington Ave, Albany, NY 12222, United States
推荐引用方式 GB/T 7714	Wallace B.,Minder J.R.. The impact of snow loss and soil moisture on convective precipitation over the Rocky Mountains under climate warming[J],2021,56(2021-09-10).
APA	Wallace B.,&Minder J.R..(2021).The impact of snow loss and soil moisture on convective precipitation over the Rocky Mountains under climate warming.Climate Dynamics,56(2021-09-10).
MLA	Wallace B.,et al."The impact of snow loss and soil moisture on convective precipitation over the Rocky Mountains under climate warming".Climate Dynamics 56.2021-09-10(2021).