DOI: 10.1007/s00382-015-2867-8
Scopus记录号: 2-s2.0-84944614879
论文题名: Possible role of pre-monsoon sea surface warming in driving the summer monsoon onset over the Bay of Bengal
作者: Li K. ; Liu Y. ; Yang Y. ; Li Z. ; Liu B. ; Xue L. ; Yu W.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2016
卷: 47, 期: 2017-03-04 起始页码: 753
结束页码: 763
语种: 英语
英文关键词: Bay of Bengal
; Intra-seasonal oscillation
; Monsoon onset
; SST
英文摘要: Sea surface temperature (SST) reaches its annual maximum just before the summer monsoon onset and collapses soon after in the central areas of the Bay of Bengal (BoB). Here, the impact of the peak in the pre-monsoon SST on triggering the earliest monsoon onset in the BoB is investigated, with a focus on the role they play in driving the first-branch northward-propagating intra-seasonal oscillations (FNISOs) over the equatorial Eastern Indian Ocean (EIO). During the calm pre-monsoon period, sea surface warming in the BoB could increase the surface equivalent potential temperature (θe) in several ways. Firstly, warming of the sea surface heats the surface air through sensible heating, which forces the air temperature to follow the SST. The elevated air surface temperature accounts for 30 % of the surface θe growth. Furthermore, the elevated air temperature raises the water vapor capacity of the surface air to accommodate more water vapor. Constrained by the observation that the surface relative humidity is maintained nearly constant during the monsoon transition period, the surface specific humidity exhibits a significant increase, according to the Clausius–Clapeyron relationship. Budget analysis indicates that the additional moisture is primarily obtained from sea surface evaporation, which also exhibits a weak increasing trend due to the sea surface warming. In this way, it contributes about 70 % to the surface θe growth. The rapid SST increase during the pre-monsoon period preconditions the summer monsoon onset over the BoB through its contributions to significantly increase the surface θe, which eventually establishes the meridional asymmetry of the atmospheric convective instability in the EIO. The pre-established greater convective instability leads to the FNISO convections, and the summer monsoon is triggered in the BoB region. © 2015, The Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/53597
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: Center for Ocean and Climate Research, First Institute of Oceanography, SOA, Qingdao, China; Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China; University of the Chinese Academy of Sciences, Beijing, China; Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
Recommended Citation:
Li K.,Liu Y.,Yang Y.,et al. Possible role of pre-monsoon sea surface warming in driving the summer monsoon onset over the Bay of Bengal[J]. Climate Dynamics,2016-01-01,47(2017-03-04)