近40a甘南高原日照时数变化趋势及影响因子  

Variation Trend Analysis on Sunshine Duration and Its Impact Factors in Gannan Plateau in Recent 40 Years

作　　者：王建兵[1,2] 敖泽建 陈洋 

机构地区：[1]中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室中国气象局干旱气候变化与减灾重点开放实验室,甘肃兰州730020 [2]甘肃省甘南州气象局,甘肃合作747000

出　　处：《干旱气象》2014年第1期93-98,共6页Journal of Arid Meteorology

基　　金：甘肃省气象局"甘南高原对流云的研究"和"甘南州强对流天气指标体系"课题共同资助

摘　　要：利用甘南高原8个气象站1971～2010年的日照时数地面观测资料，对其近40 a日照时数的时空变化特征进行了分析。发现：甘南高原年日照时数的空间分布特征呈西多东少；月际变化表现出明显的3峰3谷的特征；20世纪70～80年代是甘南高原日照时数最少的时期，而20世纪90年代日照时数明显增加，进入21世纪后，高原西部日照时数出现了减少的趋势，而东部仍以偏多为主。突变分析表明，甘南高原日照时数的变化可分为3种类型：第1类为出现增大突变，并且仍持续上升的，主要有卓尼、迭部；第2类为出现增大突变，但目前开始减少，主要有夏河、玛曲、舟曲；第3类为未出现突变的，有合作、碌曲、临潭。日照时数的变化与气温、水汽压、云量、降水和风速的变化密切相关，造成甘南高原西部与东部日照时数不同变化趋势的主要原因是降水量和风速的不同变化。Gannan Plateau located in the southwest of Gansu Province and in the northeast border region of the Tibetan Plateau,which is an important water conserving and supplying area in the upriver regions of Yellow River.It plays an important role in the mainte-nance of water resource and eco-environmental security of the Yellow River basin.Due to the impact of climate change and the man activities,the ecology and environment of Gannan Plateau had obviously changed.So,this paper carried out the research about the change characteristic of sunshine duration in Gannan Plateau in order to provide the reference for the study of climate change in the Ti-betan Plateau. 〈br〉 Based on the meteorological data of sunshine duration at 8 weather stations in Gannan Plateau from 1971 to 2000,the temporal and spatial variations of sunshine duration and its impact factors were studied by using trend analysis,Mann-Kendall test and principal component analysis,etc.The results show that the spatial distribution of annual average sunshine duration in the Gannan Plateau was far from uniformity.The sunshine duration in the western part of the Gannan Plateau was great more than that in the eastern part.The monthly variation of sunshine duration in the Gannan Plateau showed 3 peaks and 3 troughs.The sunshine duration in the 1970s and 1980s was least,increased obviously in the 1990s and the sunshine duration in the western of the Gannan Plateau showed a decreasing tendency in the 2000s,while in the eastern it showed an contrary increasing tendency.Furthermore,the mutation analysis shows that there were 3 types of sunshine duration variety in the Gannan Plateau.The first type was the detected mutation,the sunshine duration was still increasing,such as Zhuoni and Diebu counties,the second was the detected mutation,but the sunshine duration showed a de-creasing trend,such as Xiahe,Maqu and Zhouqu,and the third was no mutation,such as Hezuo,Luqu and Lintan.The variety of sunshine duration was closely related with the temperature,water vapor press

关 键 词：日照时数 变化特征 影响因子 甘南高原 

分 类 号：P422.11[天文地球—大气科学及气象学]