Detrended Fluctuation Analyses of Rainfall Intensities: A Case Study

Abstract

The main source of the irregularity in the rainfall regimes is global climate change. These irregularities in the precipitation regime cause sudden and heavy rains, which increases the risk of flooding especially in cities. Therefore, the investigation of the change in precipitation intensities over time has great implications in terms of hydrology, water resources and urbanisation. In this study, rainfall intensity of Artvin meteorological station which is located in the Black Sea Region of Turkey is investigated. This station differs from the other stations in the Black Sea Region with extreme rainfall characteristics. Data of 14 standard duration rainfall intensity series with durations of 5 min to 24 h were used. First of all, two methods were applied for homogeneity control and then trend analysis was performed. Assuming that the factor destabilising the homogeneity is the trend, a detrended fluctuation analysis (DFA) was performed. After the implementation of DFA, homogeneity and trend analysis were reapplied to the data. In conclusion, it was determined that the main reason for the deterioration of rainfall intensity was the trend.