Observed trends and jumps of climate change over Lake Poyang Basin, China:1961-2003

本文利用1961-2003年间鄱阳湖流域14个气象站的气温、降水量、蒸发量等观测数据和8个主要水文站的流量数据,研究该时段内鄱阳湖流域的气候变化趋势、突变及其空间分布的差异.研究表明,鄱阳潮流域气温和降水均在1990年发生突变,继而呈现显著的上升趋势;在季节变化上,冬季平均气温在1986年发生突变,增温显著;夏季降水量和夏季暴雨频率均在1992年发生突变增加,暴雨频率增加是夏季降水量增加的主要原因;蒸发皿蒸发量和参照蒸散量均呈现显著下降趋势,该变化在夏季尤为明显.上述变化趋势均以1990s最为显著,这与长江流域气候变化趋势基本一致.在空间分布上,饶河水系、信江水系和赣江下游等气候变化更为显著.笔者认为,鄱阳湖流域气候变化在长江流域中比较突出.该流域1990s暖湿气候在加强;气温的升高、降水量和暴雨频率的增加以及蒸发量的下降强化了五河流量的增加趋势,由此可大致判定鄱阳湖流域气候变化与洪涝灾害之间可能存在的关系,这可为理解气候变化在该流域的响应和预测该流域未来可能的洪涝灾害提供依据.;Based on observed data of 14 meteorological stations and six main hydrological stations in lake Poyangbasin, the trends and jumps of temperature, precipitation, pan evaporation(PE), reference evapotranapiration(ETr) and discharge are analyzed from 1961 to 2003. The results indicate that the temperature jumped in 1990, then it dominated an upward trend ever since 1990. Significant positive trend was noticed after 1986 in winter. Asto precipitation, it changed abruptly in 1990. In 1992, the heavier rainstorm resulted in more precipitation in sum-mer. Significant negative trend of PE and ETr was found, especially in summer. It was found that summer ETr fellsharply after 1992. As for spatial distribution, significant climate change areas are found in the Raohe River basin,the Xinjiang River basin and the lower reaches of the Ganjiang River basin. The climate change trends above-men-tioned,that is coincident with the trend of the Yangtze River basin, are more obvious in 1990s. As a result, therunoff to the Lake Poyang also rose up. In 1990s, warm and humid climate tendency was strengthened. The climatechange of lake Poyang basin is much significant in the Yangtze River basin.