摘要
Reconstruction of a homogeneous temperature and precipitation series for China is crucial for a proper understanding of climate change over China. The annual mean temperature anomaly series of ten regions are found from 1880 to 2002. Positive anomalies over China during the 1920s and 1940s are noticeable. The linear trend for the period of 1880-2002 is 0.58℃(100a)-1, which is a little less than the global mean (0.60℃ (100a)-1). 1998 was the warmest year in China since 1880, which is in agreement with the estimation of the global mean temperature. The mean precipitation on a national scale depends mainly on the precipitation over East China. Variations of precipitation in West China show some characteristics which are independent of those in the east. However, the 1920s was the driest decade not only for the east, but also for eastern West China during the last 120 years. The most severe drought on a national scale occurred in 1928. Severe droughts also occurred in 1920, 1922, 1926, and 1929 in North China. It is noticeable that precipitation over East China was generally above normai in the 1950s and 1990s; severe floods along the Yangtze River in 1954, 1991, and 1998 only occurred in these two wet decades. An increasing trend in precipitation variations is observed during the second half of the 20th century in West China, but a similar trend is not found in East China, where the 20- to 40-year periodicities are predominant in the precipitation variations.
Reconstruction of a homogeneous temperature and precipitation series for China is crucial for a proper understanding of climate change over China. The annual mean temperature anomaly series of ten regions are found from 1880 to 2002. Positive anomalies over China during the 1920s and 1940s are noticeable. The linear trend for the period of 1880-2002 is 0.58℃(100a)-1, which is a little less than the global mean (0.60℃ (100a)-1). 1998 was the warmest year in China since 1880, which is in agreement with the estimation of the global mean temperature. The mean precipitation on a national scale depends mainly on the precipitation over East China. Variations of precipitation in West China show some characteristics which are independent of those in the east. However, the 1920s was the driest decade not only for the east, but also for eastern West China during the last 120 years. The most severe drought on a national scale occurred in 1928. Severe droughts also occurred in 1920, 1922, 1926, and 1929 in North China. It is noticeable that precipitation over East China was generally above normai in the 1950s and 1990s; severe floods along the Yangtze River in 1954, 1991, and 1998 only occurred in these two wet decades. An increasing trend in precipitation variations is observed during the second half of the 20th century in West China, but a similar trend is not found in East China, where the 20- to 40-year periodicities are predominant in the precipitation variations.
基金
supported by the China National Key Programme for Developing Basic Sciences(G1998040900)
the National Natural Science Foundation of China(Grant No.40205011)
