1978年前、后中国≥10℃年积温对比

Comparison of accumulated temperature above 10 ℃ before and after the year 1978 in China

利用620个气象站点的逐日平均气温分别计算了1951—1978和1979—2005年≥10℃年积温及其初日、终日,并对比分析了1978年前、后≥10℃年积温及其初日、终日和持续天数.结果表明:与1951—1978年相比,1979—2005年全国大部分地区≥10℃年积温有所增加,其增幅以东北、华北、华南地区较大;长江以北大部分地区的≥10℃年积温初日提前0～5d,长江以南大部分地区则推迟0～5d;除华南沿海和西南小部分地区的≥10℃年积温终日推迟5d以上外,其余地区则推迟0～5d;全国≥10℃年积温日数总体呈增加趋势,以0～5d和5～10d的增幅为主,各地区的差异大且连片性差.对积温变化趋势的准确掌握可为农业结构布局调整以及农业生产潜力评估提供重要依据.

By using the observation data from 620 meteorological stations in China, the annual accumulated temperature above 10 ℃, its starting date, ending date, and duration days from 1951 to 1978 and from 1979 to 2005 were calculated and compared. The results showed that in most areas of China, especially in Northeastern, North, and South China, the accumulated temperature above 10 ℃ from 1979 to 2005 was higher than that from 1951 to1978. The starting date of accumulated temperature above 10 ℃ in northern areas of Yangtze River was 0-5 days earlier from 1979 to 2005 than from 1951 to 1979, while that in southern areas of Yangtze River was 0-5 days later from 1979 to 2005 than from 1951 to 1979. The ending date of accumulated temperature above 10 ℃ in most areas of China was delayed 0-5 days, except that in near coastal areas of South China and some regions of Southwest China, which was delayed more than 5 days. The duration days of accumulated temperature above 10 ℃ were generally increased by 0-5 days or 5-10 days in most areas of China, but the increase amplitude was different and could not be linked together in different areas. To accurately know the changing trend of accumulated temperature above 10 ℃ could provide an important basis for the adjustment of agricultural production structure and the assessment of agricultur al potential productivity.