Detrended fluctuation analysis of daily rainfall records of the entire China

In our analysis, we consider daily rainfall records y(n) from 3825 areas covering entire China. The daily rainfall records is 50 years long from 1961 to 2011. We study the statistical properties of the daily rainfall data and return intervals Tq between two consecutive rainfall records above some threshold q. Using the detrended fluctuation analysis (DFA) method to analyze the long-term correlation properties of the rainfall record y(n) and return intervals Tq, we find that the long-term correlation is not exist in rainfall record, while a weak long-term correlation is found in return intervals, pointing to a random regulation of rainfall dynamics. Then, we further analyze the probability distribution function (PDF) of the rainfall record and return intervals of all the 3825 areas, and find that all the PDF obey a power-law distribution.