青海南部高原近450年来春季最高气温序列及其时变特征  

SERIES OF SPRING MAXIMUM TEMPERATURE IN SOUTHERN QINGHAI PLATEAU AND ANALYSIS OF ITS VARIATIONS DURING THE LAST 450 YEARS

作　　者：靳立亚[1] 秦宁生[2] 勾晓华[1] 陈发虎[1] 李静[1] 

机构地区：[1]兰州大学资源环境学院中德干旱环境联合研究中心,西部环境教育部重点实验室,兰州730000 [2]青海省气候资料中心,西宁810001

出　　处：《第四纪研究》2005年第2期193-201,共9页Quaternary Sciences

基　　金：科学技术部社会公益项目(批准号: 2001DIB10085);国家杰出青年科学基金项目(批准号: 40125001)资助

摘　　要：根据采自青海南部高原曲麻莱、治多地区的圆柏树轮样芯建立的树木年轮年表,重建了近450年来高原春季(4～6月)的最高气温序列.采用多窗谱分析、小波分析和Yamamoto突变检测分析等方法综合研究了重建的高原春季最高气温序列的准周期性及多尺度突变特征.结果显示,青海南部高原地区春季最高气温的变化存在较明显的31～54年低频和2～4年高频准周期波动特征.在30～54年时间尺度上,青海南部高原春季最高气温变化经历了1622～1639年、1798～1816年、1896～1913年和1933～1951年的偏冷期以及1684～1703年、1779～1797年、1817～1835年和1914～1932年的偏暖期.分析还发现,青南高原地区春季最高气温在冷暖期的转换过程中存在着较明显突变现象,在30～40年时间尺度上,Tm序列在1610年、1668年、1816年、1915年和1934年前后的突变是明显的.交叉相关分析显示,在滞后7.5年左右,青海南部高原春季最高气温波动与太阳黑子周期长度的变化呈显著负相关.Based on two tree ring-width chronologies of Sabina tibetica developed from cores sampled in Qumalai and Zhiduo, Southern Qinghai Plateau, a series of averaged spring (from April to June) maximum temperature (T m) was retrieved for the last 450 years. By using the Multi-Taper Method of Spectrum Analysis (MTM), method of wavelet transform analysis, and the Yamamoto method, the quasi-periodicities and multiple time-scale features of the T m were studied. The result shows that there exist pronounced lower-frequency periodicities of 31~54 years and higher-frequency variations of 2~4 years. On time scales of 31~54 years, the spring maximum temperature of Southern Qinghai Plateau experienced warmer periods in the years of 1622~1639, 1798~1816, 1896~1913 and of 1933~1951 as well as colder periods in the years of 1684~1703, 1779~1797, 1817~1835 and of 1914~1932. The results also indicate that the transformation periods of the spring maximum temperature from colder spell to warmer spell or the reverse was relatively abrupt. On time scales of 30~40 years, the series of T m existed apparent rapid changes around the years of 1610, 1668, 1816, 1915 and 1934. A 7.5-year lag cross-correlation analysis indicates that the changes of the spring maximum temperature in Southern Qinghai Plateau is negatively significant (at the 0 01 level) related to the changes of solar cycle length during the period of 1550~1995,showing the influence of the solar activity on temperature changes over the Qinghai Plateau. Additionally, the variation amplitudes of the series of T m tend to be weak in the past 50 years,and both on 32- and 64-year time scales, the spring maximum temperature showed a decreasing trend. It started at 1961 on the 64-year time scale and at 1991 on the 32-year time scale.

关 键 词：青海南部高原 树轮年表 最高气温 准周期 突变 

分 类 号：P468[天文地球—大气科学及气象学] P423