1980-2013年青藏高原气候时空变化特征研究

Spatial and Temporal Patterns of Climate in the Tibetan Plateau(1980-2013)

为研究气候变暖背景下青藏高原的气候变化特征,对青藏高原及周边气象站点(1980-2013年)的气象数据整理分析,采用一元线性回归模型和空间插值分析气候要素的时空变化特征,以滑动t检验与Mann-Kendall检验对气候要素突变分析。得出(1)最高气温显著上升趋势(0.55℃/10a),突变(1997年)后增温速率更大。最低气温和平均气温也显著上升趋势,其突变时间节点一致(1995年),且突变前的增温速率均大于突变后的。高温阈值和低温阈值空间上均呈现东南-西北高、东北-西北次之、中间低的分布特征。(2)最大降水非显著下降趋势(-6.22 mm/a),突变(1994年)前降雨增加率更大;而最小降水显著缓慢上升趋势(0.27 mm/a),但突变(2002年)后降雨增加速率更大。最大降水和最小降水阈值在空间上由西北到东南上升,具有明显的条带分布特征。

In order to study the regional variation characteristics of climatic elements in Tibet Plateau （TP） under the background of global warming,climatic elements datum of the meteorological stations around TP （1980-2013） are analyzed in this paper.A linear regression model and spatial interpolation are used to explore the spatial-temporal characteristics of climatic elements,sliding t test and Mann-Kendall test are applied for abrupt changes analysis.The results show that：（1）The highest temperature shows a significant increased trend （0.55 ℃/10a）,a higher increase rate of the highest temperature is found after the abrupt point （1997）.The minimum temperature and mean temperature also show significant increase features.The abrupt points of the minimum temperature and mean temperature are 1995,both of them show a higher increase rate before the abrupt point 1995.The spatial distribution of the maximum temperature threshold and minimum temperature threshold present higher in the southeast-northwest,followed by northeast-northwest,then the lowest value in middle region.（2）The highest precipitation show a non-significant decreased trend （-6.22 mm/a）,and a higher increase rate of the highest precipitation is found before the abrupt point （1994）.In addition,the minimum precipitation shows a significant increased features （0.27 mm/a）,and a higher increase rate of the minimum precipitation is found after the abrupt point （2002）.The threshold value of the maximum precipitation and minimum precipitation presented a rising trend from the northwest to southeast regions with stripe characteristic.