滨州市(鲁北地区)干旱气候特征及趋势分析

利用滨州市1971~2000年降水、气温、湿度等资料,解析滨州市(鲁北地区)干旱化趋势。结果表明,滨州市降水量每10年减少26mm。升温达0.03℃/a,夏秋季温度升高,其中20世纪90年代比70年代高出0.5℃以上,特别是冬季竟高出了1.4℃。这与全国乃至全球变暖趋势一致。通过对滨州1971~2000年观测资料中有关数据的计算,滨州市近30年气候变化已呈现出年降水量总体上持续降低、气温总体上持续升高,且当地水热平衡已明显呈现出新的关系和规律的状况。滨州市年湿润指数呈明显下降趋势,气候干旱化。湿润指数平均10年减少0.057,主要原因是降水量逐年减少,气温逐年上升。受其影响,蒸散量平均每10年增加26.85 mm。滨州市这种干旱化趋势与副高综合指数、副高面积和强度指数的年代际变化与极涡中心平均纬度和平均经度的年代际变化有直接关系。

Climate Characteristic Analysis of Binzhou City,Lubei Region

The trend of drought in the city of Binzhou(Lubei region) was analyzed,with the data of precipitation,air temperature and humidity during 1971 to 2000.It was found that the precipitation was decreasing by 26 mm every 10 years,while the temperature was increasing by 0.3 ℃ per decade.The temperature in the summer and autumn was increasing.And the temperature in 1990's was higher over 0.5 ℃ than that in 1970's,while the temperature in the winter was up to 1.4 ℃.This was inaccord with the global warm-up.It was also found that in the recent 30 years the general climate was in the trend of decreasing precipitation and increasing temperature,and the local water-warm balance was in a brand new situation.The annual humidity was in a trend of decline,and the climate was in a situation of drought.Humidity index was in decreasing by 0.057 every 10 years.The main reason was that precipitation was decreasing while the temperature was increasing every year.Therefore,transpiration was increasing by 26.88 mm every 10 years.So the situation of drought in Binzhou was directly related to decadal changes of subtropics high atmospheric pressure index,subtropics high atmospheric acreage and intensity and decadal changes of pole-whorl average latitude and average longitude.