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DOI	10.5194/cp-15-449-2019
	The response of tropical precipitation to Earth's precession: The role of energy fluxes and vertical stability
	Jalihal C.; Helena Catharina Bosmans J.; Srinivasan J.; Chakraborty A.
发表日期	2019
ISSN	18149324
起始页码	449
结束页码	462
卷号	15 期号:2
英文摘要	The changes in Earth's precession have an impact on the tropical precipitation. This has been attributed to the changes in seasonal solar radiation at the top of the atmosphere. The primary mechanism that has been proposed is the change in thermal gradient between the two hemispheres. This may be adequate to understand the zonal mean changes, but cannot explain the variations between land and oceans. We have used a simple model of the intertropical convergence zone (ITCZ) to unravel how precipitation changes with precession. Our model attributes the changes in precipitation to the changes in energy fluxes and vertical stability. We include the horizontal advection terms in this model, which were neglected in the earlier studies. The final response of the land and oceans is a result of complex feedbacks triggered by the initial changes in the insolation. We find that the changes in precipitation over the land are mainly driven by changes in insolation, but over the oceans, precipitation changes on account of changes in surface fluxes and vertical stability. Hence insolation can be a trigger for changes in precipitation on orbital timescales, but surface energy and vertical stability play an important role too. The African monsoon intensifies during a precession minimum (higher summer insolation). This intensification is mainly due to the changes in vertical stability. The precipitation over the Bay of Bengal decreases for minimum precession. This is on account of a remote response to the enhanced convective heating to the west of the Bay of Bengal. This weakens the surface winds and thus leads to a decrease in the surface latent heat fluxes and hence the precipitation. © 2019 The Author(s).
语种	英语
scopus关键词	energy flux; heating; intertropical convergence zone; latent heat flux; Northern Hemisphere; precipitation (climatology); solar radiation; Southern Hemisphere; surface wind; temperature gradient; Bay of Bengal; Indian Ocean
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/153220
作者单位	Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore, India; Divecha Centre for Climate Change, Indian Institute of Science, Bangalore, India; Department of Environmental Science, Radboud University, Nijmegen, Netherlands; Faculty of Geosciences, Utrecht University, Utrecht, Netherlands; Royal Netherlands Meteorological Institute (KNMI), De Bilt, Netherlands
推荐引用方式 GB/T 7714	Jalihal C.,Helena Catharina Bosmans J.,Srinivasan J.,et al. The response of tropical precipitation to Earth's precession: The role of energy fluxes and vertical stability[J],2019,15(2).
APA	Jalihal C.,Helena Catharina Bosmans J.,Srinivasan J.,&Chakraborty A..(2019).The response of tropical precipitation to Earth's precession: The role of energy fluxes and vertical stability.Climate of the Past,15(2).
MLA	Jalihal C.,et al."The response of tropical precipitation to Earth's precession: The role of energy fluxes and vertical stability".Climate of the Past 15.2(2019).