川西高原6-7月最低气温场重建研究

 经过单相关普查,选择川西高原甘孜、阿坝两州的14个树木年轮宽度年表和14个气象站的1961—2005年6—7月最低气温资料分别建立树轮宽度场和最低气温场。计算树轮宽度场和最低气温场的典型相关系数,发现两个场的第一特征向量和第三特征向量有较好的相关性。利用多元线性回归模型分别重建14个地点的1787—2005年6—7月最低气温序列和川西地区平均气温序列,重建6—7月最低气温场。分析最低气温重建场发现,第一特征向量能较好地反映川西地区的冷暖变化。在近两个世纪里,川西地区最低气温场第一特征向量的方差贡献率在增加,而最低气温场的收敛速度在减慢。

Reconstruction of Minimum Temperature Field in June-July During 1787-2005 in the West Sichuan Plateau

Single correlation coefficients between tree ring width chronologies and minimum temperature data from 14 weather stations at the west Sichuan plateau were calculated,and the 14 tree-ring width chronologies and minimum temperature series in June-July during 1961-2005 were selected to build tree-ring width field and minimum temperature field in the area.Calculation of typical correlation coefficients between tree-ring width field and minimum temperature field showed the first eigenvector and third eigenvector of the two fields were significantly correlative.The minimum temperature sequences in June-July during 1787-2005 of the 14 stations and a regional average minimum temperature series were reconstructed using Multiple Linear Regression Model.Analysis of reconstructed minimum temperature field during 1787-2005 showed the first eigenvector of the field responded well to warm/cold change periods in west Sichuan,and variance contribution of the first eigenvector of the field was enhanced in past two centuries,and convergence rate of the field decreased.