近20年气候变暖对东北农业生产水热条件影响的研究

IMPACTS OF CLIMATE WARMING ON THERMAL AND MOISTURE CONDITIONS IN NORTHEAST CHINA IN RECENT 20 YEARS

针对东北气候变化影响研究中对增温正效应关注较多 ,而对水热匹配等综合影响研究不够的情况 ,利用东北地区 1 961～ 2 0 0 0年 56个气象站的气象资料 ,对近 2 0年东北气候变暖的特点 ,温度升高的同时大气干湿程度及水热匹配状况的变化等相关现象进行了较详细的分析。提出东北气候变暖主要表现于冬季 ,2 0世纪 90年代变暖明显 ,南部大于北部 ;夏季增温幅度有限 ,不很稳定 ,仍时有温度偏低发生 ,并同时出现高温日数增多等极端异常气候事件 ;最低温度升高幅度大于最高温度的升高幅度 ,导致温度日较差变小 ,冬季更加明显 ;大气水分盈亏状况和水热状况在 1 0年时间尺度上没有明显的变化 ,但 2 0世纪 90年代中后期出现暖干化趋势 ,并由春季转至夏季 ,西部和南部比较明显 ,对农作物不利等结论。为克服盲目性 ,客观评估东北气候变化及其影响 。

The characteristics of climate warming, instability and extreme climate events as well as changes in atmospheric moisture and the corresponding thermal and moisture conditions in Northeast China in recent 20 years are analyzed based on data in 1961-2001 in 56 meteorological stations. The results show: (1) The temperature increment amplitude in winter is significant; the 1990's climate warming is stronger than the 1980's; and the increment in the southern part is larger than that in the northern part. (2) The temperature increment in summer is limited; the temperature variance is unstable, and extreme climate events such as days of high temperature occur frequently. (3) The increment in minimum temperature is much larger than that in maximum temperature, which results in the reduction of temperature diurnal range; the change is more obvious in winter. (4) There is no significant change in atmospheric moisture deficit and the corresponding thermal and moisture conditions at 10 year scale; however, there are evidences of warming and drying in recent 5 years and the warming and drying periods occur frequently in summer as well as in the southern and western parts. Warming and drying in summer is unfavorable to crops.