Characterization of precipitation through on climate extreme indicators at the Casablanca meteorological station, 1980-2018

Abstract

The study of rainfall patterns and extreme events is fundamental to understanding climate variability and mitigating its impacts on society and the economy, particularly in vulnerable regions such as the Caribbean. The objective of this work was to characterize rainfall patterns based on climate extreme indicators at the Casablanca meteorological station during the period 1980-2018. Daily 24-hour rainfall series, obtained from the database of the Cuban Institute of Meteorology, were used. The methodology included rigorous quality control with a threshold of three standard deviations, a homogeneity test using the RHtest, and the calculation of eight ETCCDI indicators (Rx1d, Rx5d, R10, R20, R100, R95p, R99p, and PRCPTOT) using the RClimdex software. The main results showed that the maximum precipitation in a single day (Rx1d) increased slightly (0.28 mm/decade), as did the precipitation associated with the 99th percentile (R99p, 10.39 mm/decade). In contrast, the maximum over five consecutive days (Rx5d) decreased (-6.04 mm/decade), as did the number of days with rainfall ≥10 mm (R10, -0.34 days/decade) and ≥20 mm (R20, -0.52 days/decade), the precipitation at the 95th percentile (R95p, -4.53 mm/decade), and the total annual precipitation (PRCPTOT, -9.08 mm/decade). It was concluded that, although mixed trends were observed (increases in some extreme indicators and decreases in others), none of the changes were statistically significant, demonstrating high natural variability without clear modifications in rainfall extremes during the analyzed period.