Based on the TRMM(Tropical Rainfall Measuring Mission) 3B43 precipitation data,the Mann-Kendall test was performed and the Hurst index was calculated at the pixel scale to analyze the spatial-temporal dynamics of precipitation in global mid-low latitudes from 1998 to 2010.Furthermore,the "Monthly Calendar" and the seasonal evolvement map were drawn.It shows that,summers and early winters are the rainy period in a year.Significant fluctuations of monthly precipitation in the past 13 years can be observed.Over all,the precipitation shows a decreasing trend from the low latitude to the high latitude.Precipitation in the ocean is more than that on the land and therefore very significant sea-land gradient characteristics can be found.On monthly scale,the changing trends of precipitation in most areas are ’increasing but not significant’ or ’decreasing but not significant’,however,there’re very strong self-similarity and long-range dependence for the 12 monthly time sequences of precipitation data.December shows the most prominent spatial differences of precipitation variation while March is the least significant one.On seasonal scale,more than 98% areas have very strong self-similarity and long-range dependence for the 4 seasonal time sequences of precipitation data;the spatial differences of precipitation variation are very significant in the seasonal evolvement map.The results and conclusions in this study are aimed at providing a useful reference on the research of global water cycle,global climate change and so on.
修改评论