时间滞后对全球温度场关联性的影响

基于美国国家环境预报中心/美国国家大气研究中心以及欧洲中期天气预报中心发布的再分析资料,构建了考虑时间滞后情况下的全球温度场关联矩阵,分析了时间滞后对全球温度场关联性时空特征的影响.结果表明:随着滞后时间的增加,全球温度场的关联性总体呈逐渐减弱的趋势,但对应不同的滞后时间其规律也不同,在滞后1—30 d的情况下,可根据全球平均关联系数C_glb的下降 关键词： 温度场 关联矩阵 时间滞后

Influence of time delay on global temperature correlation

With time delay under consideration, temperature correlation matrixes are constructed based on the reanalysis of temperature data provided by National Centers for Environmental Prediction/National Center for Atmospheric Research and European Centre for Medium-Range Weather Forecasts. Results indicate that the correlation of global temperature decreases with lag time, and the rate is dependent on time lag. We divide the lag time (1—30 d) into three segments, i.e., 1—7 d, 8—20 d and 21—30 d according to the decrease rate of global average correlation coefficient C_glb. When the lag time is in a specific interval (8—20 d), C_glb is unstable, which may explain the difficulty in long range weather forecast of 10—30 d. The spatial distribution of the global temperature correlation keeps stable for different lag times, while the numerical change shows zonal distribution on the whole, and that the most of Asia and the equatorial central and eastern Pacific show countertrend to other parts of similar latitudes.