Drivers of rainfall trends in and around Mainland Southeast Asia
Drivers of rainfall trends in and around Mainland Southeast Asia
复制标题
DOI：
10.3389/fclim.2022.926568
复制
发表时间：
2022-09
期刊：
影响因子：
--
通讯作者：
N. Skliris;R. Marsh;I. Haigh;Melissa Wood;J. Hirschi;S. Darby;N. P. Quynh;N. Hung
中科院分区：
文献类型：
--
作者：
N. Skliris;R. Marsh;I. Haigh;Melissa Wood;J. Hirschi;S. Darby;N. P. Quynh;N. Hung
自20世纪50年代以来，观测雨量计/卫星和再分析数据集的平均和极端降雨的趋势在东南亚大陆（MSEA）和周围进行了评估。雨量计资料显示，自1979年以来，越南和半岛西北部的年平均降水量和各种极端降水指数都有超过50%的强劲增长。ENSO的远程影响可能部分解释了最近几十年来主要的拉尼娜状态，最近的降水趋势朝着更强烈的区域水文循环。MSEA降水的增加也与东南亚季风强度的增加以及1979-2018年季风活动中心向MSEA的北移有关。变暖驱动的蒸发量增加，在邻近海域通常喂养降水在MSEA与转向主要是积极的阶段的热带印度洋的两个主要的自然气候变率模式，即印度洋偶极子和印度洋盆地模式。使用ERA 5再分析数据进行的水分收支分析表明，海洋水分输送沿着典型的冬季和夏季水分路径向MSEA增加。然而，结果表明，在夏季的大部分增加的水分从海洋水分来源最终降水的海洋区域邻近MSEA与ERA 5不能产生所观察到的积极的趋势，夏季大陆降水。另一方面，ERA 5显示，根据雨量计数据，MSEA冬季降水明显增加，这与来自热带西太平洋和南海的水分输送强烈增加有关。
Observational rain gauge/satellite and reanalysis datasets since the 1950s are evaluated for trends in mean and extreme rainfall in and around Mainland Southeast Asia (MSEA). Rain gauge data indicate strong increases exceeding 50% in both annual mean precipitation and various extreme precipitation indices over Vietnam and the northwestern part of the peninsula since 1979. The remote influence of ENSO may partially explain the recent precipitation trend toward a more intense regional hydrological cycle, in response to predominant La Niña states over recent decades. Increasing precipitation in MSEA is also associated with increased monsoon intensity in southeast Asia and a northward shift of the monsoon activity center toward MSEA over 1979–2018. Warming-driven evaporation increases were obtained over the adjacent seas typically feeding precipitation over MSEA associated with a shift toward predominantly positive phases of the two major natural climate variability modes of the tropical Indian Ocean, namely the Indian Ocean Dipole and the Indian Ocean Basin Mode. A moisture budget analysis using ERA5 re-analysis data showed increasing oceanic moisture transports along the typical winter and summer moisture pathways toward the MSEA. However, results show that during summer the major part of increased moisture from the oceanic moisture sources ends up as precipitation over the oceanic regions adjacent to MSEA with ERA5 not being able to produce the observed positive trends in summer continental precipitation. On the other hand, ERA5 reveals pronounced increases in winter precipitation over the MSEA, in accordance with rain-gauge data, associated with strongly increasing transport of moisture originated from the western tropical Pacific and the South China Sea.