Statistical analysis of extreme sea levels in the Red Sea

Abstract

Coastal areas frequently experience high-sea-level events that can cause property damage and loss of life. From a coastal engineering perspective, accurately estimating the probability of extreme sea levels is crucial for designing robust coastal structures. While these estimates are typically based on long-term tide-gauge observations, sea-level hindcasts are also used when available data are limited. This study obtained estimates of extreme sea-level probabilities for the Red Sea, utilizing a 30-year dataset (1993–2022) containing hourly sea level records reconstructed using a surge model (MOG2D), a global tide model (FES2014), and sea-level anomaly data from satellite altimeters. The reconstructed sea-level data were validated against measurements from six tide gauges along the eastern Red Sea and demonstrated good agreement. Spatial maps of extreme sea levels indicated values ranging from approximately 0.4 to 1.8 m. The highest estimates for the 100-year return level were found in the northern Gulf of Suez, with elevated values also observed in the northern and southern Red Sea. Furthermore, we assessed the impact of sea-level rise on extreme sea-level probabilities. Our results revealed that even small increments in the mean sea level could lead to considerable changes in extreme sea-level probabilities across most of the Red Sea. Overall, our findings are valuable for various coastal development projects along the Red Sea coast and for improving coastal vulnerability assessments.