关键词：
干燥指数;干湿状况;滇中地区;时空分布;变化趋势
摘 要：
基于1970—2014年云南省滇中地区9个气象站点的气象数据,以Penman-Monteith公式为基础计算干燥指数,结合M-K检验法和5a滑动平均法,分析了滇中地区干湿状况的时空变化规律。结果表明:(1)滇中地区实际蒸散量与潜在蒸散量呈显著正相关关系,说明Penman-Monteith公式计算的潜在蒸散量适合滇中地区;(2)滇中地区干燥指数多年平均值为1.55,属于半干旱区,近45年干燥指数整体呈上升趋势,上升幅度约为0.063/10a,春季干燥指数呈减小趋势,减小幅度约为0.025/10a,夏季、秋季和冬季均干燥指数呈上升趋势,其中秋季呈现显著上升趋势,上升幅度依次为0.024/10a,0.111/10a,0.476/10a,M-K检验结果表明干燥指数发生突变的时间主要集中在20世纪70年代中前期和2009年左右;(3)滇中干燥指数受降水影响最为显著,整体上呈中间高,东西低的分布特征,冬季最干,春季较秋季干,夏季最湿;(4)在年尺度上变干趋势由中西部向东部越来越明显,春季变湿趋势由东部向中西部越来越明显,夏季变干趋势由中间向东西部越来越明显,秋季变干趋势由西北向东南越来越明显,冬季变润区主要分布在中部、东北部和东南部,变干区主要分布在西北部。
译 名：
Variation Characteristics of Dry-Wet Conditions in Central Yunnan in Recent 45 Years Based on Dry Index
作 者：
CAO Yan;WANG Jie;HUANG Ying;ZHANG Lei;QI Na;Yunnan Institute of Water Resources and Hydropower Research;
关键词：
dry index;;dry-wet conditions;;central Yunnan;;spatial and temporal distribution;;variation trend
摘 要：
Based on the meteorological date of 9 stations in central Yunnan from 1970 to 2014,the dry index was estimated using the FAO Penman-Monteith formula,and the temporal and spatial variation characteristics of dry-wet conditions in central Yunnan were analyzed by Mann-Kendall test and 5-year moving average method.The result showed that there was a significant positive correlation between the actual evapotranspiration and the potential evapotranspiration in central Yunnan.The results also showed that:(1)the potential evapotranspiration calculated by Penman-Monteith formula was suitable for central Yunnan Province;(2)the annual average value of dry index was 1.55,the overall dry index had increased with an increasing rate of 0.063/decade from 1970 to 2014,the dry index had decreased with a decreasing rate of 0.025/decade in spring,the dry index had increased with an increasing rate of 0.024/decade,0.111/decadeand 0.476/decade in summer,autumn and winter,repectively,which indicated the significant upward trend in autumn,the abrupt change of dry index happened in 2009 and around 1970 s;(3)the dry index was most affected by precipitation in central Yunnan,the main space characteristics of dry index was high in central and low in east and west,the maximum value of dry index appeared in winter,and the value of dry index in spring was higher than that in autumn,the minimum value of dry index occurred in summer;(4)at the annual scale,the dry trend was more and more obvious from the midwest to the east,the wet trend was more and more obvious from the east to the midwest in spring,the dry trend was more and more obvious from the middle to the east and the west in summer,the dry trend was more and more obvious from northwest to southeast in autumn,the wetweed areas mainly distributed in the central region,northeast and southeast,the drying area mainly distributed in the northwest in winter.
