摘要
降水量及其季节分配与降水形式变化一直是全球气候变化研究的热点之一。使用青藏高原72个气象站点1961-2015年的逐日降水量资料,基于趋势、波动特征和极端事件相结合的新视角,全面剖析了该地区近55年降水量的趋势、波动与极端事件变化。结果表明:(1)时间上,近55年青藏高原年降水量、年最大日降水量和一年中日降水量≥10 mm的天数分别以6. 59 mm·(10a)^(-1)、0. 33 mm·(10a)^(-1)和0. 26 d·(10a)^(-1)的速率显著增加,增幅分别达到36. 2 mm、1. 8 mm和1. 4 d。(2)空间上,过去55年青藏高原绝大部分地区年降水量增加,不稳定性增强。但波动变化存在较大的地区差异,广大的中西部地区年降水量波动缓慢增强,而高原东部地区自北向南波动快速增强区与快速减弱区相间分布,极端降水强度与频数亦有类似的变化格局。(3)趋势、波动与极端变化三者组合预示,青藏高原东部的祁连山地区、柴达木盆地东部、青海湖流域与长江源区极端降水事件将明显增加,高原中西部地区发生强降水的可能性亦增加,而高原东南缘地区干旱事件将增多。
Changes of precipitation, the seasonal distribution and pattern have always been one of the hotspots of global climate change research. From new perspectives of combinations of trend, fluctuation characteristics and extreme event, the changes of trend, fluctuation and extreme event of precipitation are analyzed using daily precipitation data from 72 meteorological stations on the Tibetan Plateau from 1961 to 2015. The following conclusions can be drawn:(1) Temporally, over the 55 years, the regional-averaged annual precipitation, maximum daily precipitation and the days when precipitation ≥ 10 mm had increased with the rates of 6.59 mm·(10a)-1, 0.33 mm·(10a)-1 and 0.26 d·(10a)-1, up to 36.2 mm, 1.8 mm and 1.4 d, respectively. (2) Spatially, over the 55 years, annual precipitation had increased in most areas of the Tibetan Plateau, along with an instability increase. But there were great regional differences in precipitation fluctuation variation. The annual precipitation fluctuation had increased slowly in the vast central and western regions, while in the eastern regions, the rapid increasing regions of and the rapid decreasing regions of precipitation fluctuation had alternatively distributed from north to south, and so did the extreme precipitation intensity and frequency. (3) The combination of trend, fluctuation characteristics and extreme changes had indicated that the future extreme precipitation events will likely increase obviously in the Qilian Mountains, the eastern Qaidam Basin, Qinghai Lake basin and source regions of the Yangtze River in the eastern part of the plateau, the probability of heavy precipitation will also increase in the central and western regions of the plateau, and the drought events will probably increase in the southeastern margin of the plateau.
作者
冀钦
杨建平
陈虹举
JI Qin;YANG Jianping;CHEN Hongju(State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China;University of Chinese Academy of Sciences, Beijing 100049, China)
出处
《冰川冻土》
CSCD
北大核心
2018年第6期1090-1099,共10页
Journal of Glaciology and Geocryology
基金
国家重点研发计划项目(2016YFA0602404)资助
关键词
降水量
趋势变化
波动变化
极端变化
青藏高原
precipitation
trend change
fluctuation change
extreme change
Tibetan Plateau
