1961-2010年云南日照资源的时空分布及年代际变化研究

Spatial-Temporal and Decadal Change in Sunshine Resources from 1961 to 2010 in Yunnan

利用云南省121个气象站日照时数1961-2010年逐月观测资料,采用线性趋势分析,EOF分解等方法分析了50年来云南省平均日照时数的区域变化特征,同时分析了其时空分布差异,结果表明:①日照时间在3月份达到最大,7月份达到最小;②云南大部地区日照时间在2 000h以上,在区域分布上具有西边多、东边相对较少、而南部比北部多的特点。最大中心位于金沙江流域的河谷地区,最少中心位于滇东北以北地区;云南日照时数具有局地变化的差异性及不同步性,其变化大致为北部减少,南部增加的趋势,并以哀牢山为界,以东以北为减少,以西以南则呈增加趋势;昆明及其以北地区日照时数减少最多,增加最大的区域位于腾冲、普洱;③云南日照时数最主要的分布类型具有整体性,易出现一致偏多或者一致偏少;第二种分布为西北东南向,大致呈两头多,中间少的分布;④日照时数的整体性分布具有明显的气候基本态、年际及年代际变化,总体上呈下降趋势,并在1985年发生突变;而第二种分布以气候基本态、年代际变化为主,整体上呈增加趋势,在1995年发生突变。总体上看,云南日照时间的变化与云南降水和温度的气候变化同步。

Based on monthly sunshine duration data from 1961 to 2010 collected from 121 meteorological observation stations across Yunnan province, regional variation in these data were analyzed. We found that maximum sunshine duration was in March and the minimum was in July. In most parts of Yunnan, sunshine duration was more than 2000 hours. It was abundant in the west, and was relatively small in the east, and the south was greater than the north. The maximum center was located in the valley area of the Jinshajiang River basin, and the minimum center was located in northeastem Yunnan. Sunshine duration in Yunnan shows local change differences and asynchronism as it decreased in the north but increased in the south and decreased in the east and north of Ailaoshan but increased in the west and south. Sunshine duration reduced most in Kunming and increased most in Tengchong and Pu＇ er. The main distribution of Yunnan sunshine was wholeness; the second distribution was the southeast to the northwest, roughly less in the center and more on two sides. The distribution of sunshine showed obvious inter-annual and inter- decadal variability, with a downward trend overall, and changed abruptly in 1985. The second distribution mainly presented a climate basic state and decadal variation, an overall increased trend and a catastrophe in 1995. In conclusion, changes in sunshine in Yunnan are synchronized with changes in precipitation and temperature.