近52a黄河源区降水量和气温时空变化特征

摘要

Using the precipitation and temperature data of 8 meteorological stations over the source region of the Yellow River from 1960 to 2012,the spatial-temporal variability characteristics of precipitation and temperature were analyzed by linear trend analysis,moving average method,cumulative anomaly methods and regression analysis,and the differences of precipitation and temperature change in the source re-gion of the Yellow River were revealed. The results show that a)the temperature of the source region of the Yellow River rises quickly with a rise rate of 0. 29 ℃ / 10 a. The rise rate is higher than that of the whole Qinghai-Tibet Plateau,and is considered as an abnormal warming area in China. The annual precipitation increases slightly with a rate of 1. 92 mm/ 10 a. The increase rate is lower than that of the whole Qinghai-Tibet Plateau;b)from the moving average curve for five years,the variation trends of precipitation and temperature are different in the source region of the Yellow River from 1960 to 2012,the precipitation is significant higher in the late 1970s to the mid-1980s,after 1986,the precipitation decreases rapidly until 2004,after that the precipitation continues to rise. The temperature is significant lower in the late 1970s to the mid - 1980s,after 1986,the temperature quickly rises and comes into the high temperature period;c)the seasonal varia-bility trend of precipitation and temperature is different. Precipitation in spring,summer,and winter is increased. However,precipitation in autumn shows a trend of decrease and;d)the spatial distribution of precipitation is remarkable in the source region of the Yellow River,and precipitation decreases from southeast to northwest. Temperatures are increased from west to east,north,southeast area,showing a concen-tric circle that the western region as the center,and temperatures are increased to the surroundings.%利用黄河源区8个气象台站的降水量和气温资料，采用线性趋势法、滑动平均值法、累计距平法和回归分析法，系统研究了黄河源区1960—2012年降水和气温的时空变化规律，揭示了黄河源区不同区域降水量和气温变化的差异性。结果表明：①黄河源区降水量和气温呈增加趋势，增长率分别为1．92 mm／10 a 和0．29℃／10 a，黄河源区降水量变化趋势与青藏高原一致，降水增加速率低于青藏高原的，升温幅度高于青藏高原的，为全国异常变暖区之一；②从5 a滑动平均曲线可以看出，黄河源区降水和气温变化趋势不同，降水量在20世纪70年代末至80年代中期显著偏高，1986年之后迅速减少，直到2004年又开始增加，气温在70年代末至80年代中期显著偏低，1986年之后迅速回升，进入显著高温期；③黄河源区降水量在春、夏季和冬季呈升高趋势，秋季呈减小趋势，气温在全年都呈升高趋势，降水量的增加主要发生在春季，而气温的升高主要发生在冬季；④黄河源区降水量空间变化差异显著，呈现出由东南向西北逐渐减小的变化规律，气温从西部向东部、北部和东南部地区升高，表现出以西部地区为中心，呈同心圆向四周升高的空间变化规律。