Multifractal analyses of daily rainfall time series in Pearl River basin of China

• Multifractal properties of daily rainfall data in Pearl river basin are examined.
• The universal multifractal model (UMM) and the MF-DFA are used.
• It is found that the empirical K(q)K(q) curves can be fitted very well by UMM.
• The estimated values of HH indicate that the data correspond to conserved fields.
• A relatively strong correlation between K(2)K(2) and elevation is found.

The multifractal properties of daily rainfall time series at the stations in Pearl River basin of China over periods of up to 45 years are examined using the universal multifractal approach based on the multiplicative cascade model and the multifractal detrended fluctuation analysis (MF-DFA). The results from these two kinds of multifractal analyses show that the daily rainfall time series in this basin have multifractal behavior in two different time scale ranges. It is found that the empirical multifractal moment function K(q)K(q) of the daily rainfall time series can be fitted very well by the universal multifractal model (UMM). The estimated values of the conservation parameter HH from UMM for these daily rainfall data are close to zero indicating that they correspond to conserved fields. After removing the seasonal trend in the rainfall data, the estimated values of the exponent h(2)h(2) from MF-DFA indicate that the daily rainfall time series in Pearl River basin exhibit no long-term correlations. It is also found that K(2)K(2) and elevation series are negatively correlated. It shows a relationship between topography and rainfall variability.