中亚水热资源匹配特征及敏感性分析

从水热积指数出发,基于1931—2019年Climatic Research Unit（CRU）再分析资料,运用多时序分析方法,从多时间尺度分析中亚水热资源匹配空间特征和时序变化,并进行敏感归因探究。结果表明：（1）空间上中亚水热匹配条件存在相对优劣,优势区多分布于高纬及高山高原地带,水热资源匹配较差区域分布于南部沙漠。优势区多和同期降水高值区、潜在蒸散低值区和气温低值区重合,年际水热积指数变化不明显或呈弱下降趋势;较差区域多为同期潜在蒸散和气温高值区,降水低值区,水热积指数降低且年际变幅较大。（2）中亚水热资源匹配年内存在季节差异,春秋较好、冬季次之、夏季较差;在年际尺度上,1931—1974年,水热匹配条件呈现上升趋势;1974—2000年左右,水热匹配条件波动上升;2000—2019年,水热匹配条件下降,且在1971—1980年、1981—1990年、1990—2000年发生匹配条件突变。春夏秋季水热匹配变化趋势同年际趋势大致相同,冬季波动幅度较小。（3）在春、夏及年尺度上,主导敏感性因子为平均气温因子,在秋冬两季为降水因子;在高纬、高原高山区,水热积指数变化敏感性气候因子多为降水因子;中亚南部水热积指数变化对降水敏感性减弱,平均气温敏感性增加,且北部平均气温敏感性系数绝对值略低于南部;高山高原区域对极端温度变化较为敏感。

The matching characteristics and sensitivity analysis based on the water-thermal product index for the water and thermal resources in Central Asia

Based on the water-thermal product index and the reanalysis data for the period 1931-2019 obtained from Climatic Research Unit (CRU), we examined the matching spatial characteristics and temporal variation trends of the water and thermal resources in Central Asia on a time scale by using the method of multi-time series analysis, and explored the sensitive climatic factors of water-thermal matching combined with the sensitivity coefficient. The results show that: (1) the water and thermal matching conditions in Central Asia are relative merits in space, and the dominant regions are mostly distributed at high latitudes and on alpine plateaus, while the regions with poor water-thermal matching resources are distributed in the southern deserts. Most of advantageous areas coincide with the high-value area of precipitation, low-value area of potential evapotranspiration and low-value area of air temperature in the same period, and the annual change of water-thermal product index is not obvious or shows an increasing trend. The disadvantageous areas are mostly the high-value area of potential evapotranspiration and the high-value area of air temperature in the same period, while the low-value area of precipitation has a decrease of water-thermal product index and a large inter-annual variation. (2) There were seasonal differences in the matching of water-thermal resources in Central Asia, characterized by best spring and autumn, better winter, and worst summer. On the annual scale, 1931-1974, the matching conditions of water and heat presented an upward trend; 1974-2000, the water and thermal matching conditions fluctuated; 2000-2019, the water and thermal matching condition decreased, and the water-thermal matching condition mutation was observed in periods of 1971-1980, 1981-1990, and 1990-2000. The variation trend of water - thermal matching in spring, summer and autumn was roughly consistent with the inter-annual trend, while the fluctuation range in winter was relatively small. (3) The sensitivity analysis showed that mean temperature was sensitive to the water-thermal matching conditions in spring, summer and annual scale, and precipitation in winter and autumn. In the high-latitude mountains of the study area, precipitation was dominant in the sensitive climate factors. In the southern part of Central Asia, the sensitivity of precipitation factors decreases while that of mean temperature factors increases. The absolute value of mean temperature sensitivity in the northern part of the region will be lower than that in the southern part; the high-latitude mountains were sensitive to the extreme temperature variation.