Extreme rainfall frequency analysis based on historical record

Abstract

This study delves into the complex realm of extreme rainfall events, emphasizing their causes, historical data analysis, and far-reaching impacts, with a specific focus on Singapore and Los Angeles. As global concerns surrounding the effects of global warming on the water cycle intensify, understanding the amplification of extreme rainfall events becomes crucial. The research utilizes a dataset spanning from 1950 to 2022, gathered from ERA5-Land, to analyze and forecast rainfall occurrences across various time intervals, including 10, 50, 100, 1,000, and 10,000 years.

Four probability distribution models, namely the Log Normal, Gumbel, General Extreme Values (GEV), and Log Pearson 3 (LP3) distributions, are employed to assess the goodness-of-fit with the data. The study reveals distinct variations in the rainfall patterns of the two regions, with Singapore experiencing heaviest rainfall during the northeast monsoon season and Los Angeles witnessing peak rainfall during the spring months. These findings have significant implications for urban planning, flood risk management, and infrastructure design.

The analysis of extreme rainfall intensity over time and frequency through Intensity-Duration-Frequency (IDF) curves provides critical insights for disaster management, urban planning, and climate adaptation strategies. The study underscores the importance of understanding extreme rainfall events and their implications for resilience and sustainability in the face of a changing climate, providing valuable groundwork for flood risk management and weather forecasting.