气候的不稳定性要比气温持续升高的危害性更大。以民勤荒漠区为例,运用1961—2013年的气象观测资料,分析了民勤荒漠气候在响应全球变暖过程中的不稳定性。结果表明:1 1月和4月平均气温的不稳定性增大,2月的等温日期提前10.36 d。2 12月和1月的极端最高气温的不稳定性增大,7月的极端最低气温的不稳定性增大,5月的极端最低气温的变异系数高达287.3%。3 1月降水量的不稳定性增大。同时,年降水量的稳定性增强。
Impact of climate instability to agriculture,forestry and animal husbandry production is more serious than that of continuous temperature increase. In this study,the instability of desert climate in the Minqin desert area and its response to global warming was analyzed based on the meteorological data during the period of 1961-2013. The results showed that the instability of monthly average temperature in January and April was increased,and the isothermal date of February became 10. 36 days earlier during the period from 1961 to 2013. The instability of extreme maximum temperature in December and January and that of extreme minimum temperature in July was increased. The variable coefficient of extreme minimum temperature in May was as high as 287. 3%. Instability of precipitation in January was increased. Moreover,the stability of annual precipitation was increased. Impact of climate change on local agricultural production was mainly caused by a sudden increase of extreme maximum temperature and a sudden drop of extreme minimum temperature. The analyzed results of data from other sites in the marginal zone of the desert in the Hexi Corridor also supported the conclusions in this paper. Impact of climate instability on agricultural production was more serious than that of continuous temperature increase under global warming.