摘要
为了全面认识青海湖流域气候变化时空特征,深化了解近几十年青藏高原地区气候显著变化背景,青海湖南部地区降水量时间分布与量级变化的特征,弥补对青海湖流域及其周边区域气候变化动态过程认识不足的现状,针对该区域降水量变化问题展开研究。主要利用1961—2013年青海湖南部地区5个气象站逐日及月降水量历史资料,通过线性回归、滑动平均法,分析了青海湖南部地区近53年季、年降水量变化特征及不同降水等级降水日数,并用Mann-Kendall检验降水突变特征。结果表明:青海湖南部地区年降水总体呈微弱增加趋势,增长率为4.42 mm/10 a,主要来自于春、夏、冬季降水量增加的贡献。青海湖南部地区降水除秋季减小趋势外,春、夏、冬季降水均呈增加趋势,夏季降水增加较为明显,降水量的四季变幅表现为夏季>秋季>春季>冬季。夏半年雨量和雨强呈增大趋势,且小雨雨日减小,中雨雨日和雨量增加;而冬半年小雪雪日减小,小雪强度增大。不同量级降水中,中雨雨日与雨量增多、小雨雨日、雨量与雨强均有减少。降水突变检验表明,青海湖南部地区年平均降水出现2次突变,分别为1976年和2004年,1976年突变前后年平均降水相差158.4 mm,由多雨期转为少雨期;而2004年突变则表现为从少雨期到多雨期,突变前后年平均值相差95.5 mm。
The study aims to fully understand the spatial-temporal pattern of climate change around of QinghaiLake, furthermore, to reduce the deficiency in understanding the dynamic process of climate change in the areaof Qinghai Lake basin and its surrounding areas under the condition of warming in Qinghai-Tibet Plateau.Daily and monthly rainfall data from 1961 to 2013 at five weather stations in the south region of Qinghai Lakewere used in this paper, annual and seasonal precipitation data, as well as the precipitation days in differentlevels were analyzed by linear regression and moving average method. We also tested the mutation ofprecipitation by Mann- Kendall method. The results showed that the annual rainfall had a weak increasingtrend with a growth rate of 4.42 mm per decade in the studied area in 1961-2013, it was mainly contributed by the precipitation trend in summer, spring and autumn. The tendency of precipitation showed a clear increase inspring, summer and winter except autumn, and precipitation increase in summer was more obvious. The mostwide rainfall amplitude appeared in summer, and then in autumn, spring and winter as a sequence. The amountand intensity of rainfall tended to increase in the summer half year, with a decrease trend of light rain days andan increase trend of both days and amount of moderate rain. However, in the winter half year, snow days of lightsnow declined but the intensity increased. Our analysis indicated that among the different levels ofprecipitation, there was an increased trend of days and amount of moderate rain, while there was a decreasedtrend of light rain days, amount and intensity. Precipitation mutation test indicated that two mutations occurredin 1976 and 2004 for average annual rainfall, it experienced an obvious change from rainy period into dryperiod in 1976 with a difference of average annual rainfall of 158.4 mm, in contrast, the precipitation showed achange from dry to rainy after 2004 mutation with a difference of 95.5 mm.
出处
《中国农学通报》
2015年第22期248-255,共8页
Chinese Agricultural Science Bulletin
基金
国家公益性行业(气象)科研专项"青藏高原融雪与降雪过程镶嵌的雪灾动态预报预警技术研究"(GYHY201306054)
国家自然科学基金项目"积雪变化下青海南部高原高寒草甸土壤有机碳分解与微生物属性的关联"(41173085)
"青藏高原植被变化空间异质性及其对气候变暖响应的模拟"(41173085
41061002)
关键词
突变分析
降水特征
降水日数
青海湖
mutation analysis
precipitation
raining days
Qinghai Lake
