气候变化背景下四川省气候资源变化趋势分析

Characteristics of Climate Resources under Global Climate Change in Sichuan Province

在全球气候变暖背景下,四川省气候资源也发生了相应的变化,这一变化必将对该区域的农业生产产生深远的影响。本文利用四川省1961年-2009年36个气象站点的逐日气象资料,分析了不同年代间该区域气候资源的空间分布特征。结果表明:四川省热量资源增加,平均气温、≥0℃积温和≥10℃积温呈增加趋势,空间分布呈经向带状特征,由西向东逐渐升高;气候带移动特征明显,亚热带向西扩展的面积高于暖温带和中温带;全省大部分地区日照时数减少,以盆地东北部减少最为明显;降水量在川西高原和攀枝花地区升高,而盆地大部减少;年参考作物蒸散量整体下降,减幅小于降水量的变化,盆地大部地区的年参考作物蒸散量低于高原地区。

In the context of global climate changes,characteristics of temperature and precipitation could be changed.Sichuan Province is one of thirteen major grain producing areas in China,also the only one in western China.Climate change has caused far-reaching impacts on agricultural production in Sichuan Province.In this study,characteristics of regional distribution of climate resources from 1961 to 2009 were analyzed using daily weather data from 36 typical meteorological stations located in Sichuan Province.Major results show that 1） heat resources in Sichuan Province were significantly enhanced during the study period due to global climate warming.The average temperature,and ≥ 0℃ and ≥ 10℃ accumulative air temperature markedly increased.The temperature in the plateau was greatly higher than in the basin.Spatial distribution characteristics of the heat resources showed a band shape,gradually increasing from the west to the east.Climatic zones were moving significantly.The area of the subtropical zone spreading to the west was larger than the warm temperate zone and temperate zone,which would change agricultural production and planting systems.The trend of crop boundaries was moving to a higher altitude,but it could also increase agrometeorological disasters,such as more pest and shorter crop growth period.2） Compared with the annual sunshine hour from 1961 to 1990,the annual sunshine hour decreased 119 hours from 1991 to 2009.In general,the sunshine hour decreased,especially the northeast of the basin,which would result in adverse impacts on photosynthesis.3） The annual precipitation was 961 mm during the period 1961-1990,and 924 mm during the period 1991 to 2009.The annua1 precipitation for the western plateau and Panzhihua region showed an increasing trend except for the basin showing a decreasing trend.In addition,the mean annual reference crop evapotranspiration （ET0） decreased.The decreasing tendency of ET0 was smaller than precipitation,and the annual ET0 in the basin was smaller than the plateau.In summary,in the plateau the annual average temperature,≥ 0℃ and ≥ 10℃ accumulative air temperature increased,and the precipitation also increased.The annual ET0 showed a decreasing trend,which seem to be conducive to planting boundaries moving to the west,and improving the water use efficiency.In the main agricultural growing area,i.e.,the basin,the annual average temperature,≥ 0℃ and ≥ 10℃ accumulative air temperature increased,while the sunshine hour,annual precipitation,and annual ET0 showed a decreasing trend.