1970～2009年广西贺州地区气温和降水的时空变化特征

运用距平、线性回归、最小二乘法和趋势分析等方法,对广西壮族自治区贺州市4个气象站1970-2009年月平均气温和降水资料进行分析。结果表明,1970-2009年贺州市气温呈现统计意义上的变暖趋势,其中20世纪70和80年代气温相对较低,90年代和21世纪前9年则较高,21世纪前9年年均气温比多年平均值高0.36℃。1970-2009年,贺州市年、春季、夏季、秋季和冬季气温每10年分别升高0.23、0.30、0.08、0.28、0.30℃,升温幅度东北高中西部低,春季升温幅度最大,秋季次之。贺州市年降水20世纪70、90年代相对偏高,在80年代和21世纪前9年偏低,其中80年代比多年平均值少117.80mm,90年代比多年平均值高119.35mm。1970-2009年贺州市年、春季、夏季、秋季和冬季降水量每10年分别为减少35.88、34.32、-31.51、15.30、8.97mm,1970-2009年贺州市降水量没有显著的长期变化异常,夏季降水量表现出非统计意义的上升趋势,其他季节均表现出非统计意义的下降趋势;贺州市降水量的减少速率表现为从南向北依次递减。

Spatio-temporal Variations of Temperature and Precipitation in Hezhou during 1970 - 2009

The methods of departure anomaly, regression analysis, least square and trend analysis were employed to analyze the monthly temperature and precipitation data of 4 stations in Hezhou prefecture during 1970-2009. As indicated by the results, the climate of Hezhou became warm at statistical significance level during 1970-2009, the temperature was relatively low in the 1970s and 1980s, whereas it started to rise after the 1990s which could be proved by a 0.36 ℃ temperature increase in the first nine years of 21st century. The annual, spring, summer, autumn and winter temperature increased by 0.23, 0.30, 0.08, 0.28 and 0.30 ℃ every ten years respectively during 1970-2009. The temperature increase amplitude was higher in North and East Hezhou than in Central and West Hezhou, largest in spring and then in autumn. The annual precipitation of Hezhou was relatively high during 1970s-1990s and lower in 1980s, the precipitation decreased by 117.80 mm in 1980s than in average years, while increased by 119.35 mm in 1990s than in average years. The annual, spring, summer, autumn and winter precipitation decreased by 35.88, 34.32, -31.51, 15.30 and 8.97 mm every ten years respectively, the precipitation of Hezhou during 1970-2009 presented no significant long-term variations, summer precipitation showed upward tendency without statistical sense, precipitation of other seasons all presented downward trend without statistical sense; the precipitation decrease rate of Hezhou gradually decreased from South Hezhou to North Hezhou.