Analysis of wave climate and trends in a semi-enclosed basin (Persian Gulf) using a validated SWAN model

Abstract

Results from a spectral wave model of the Persian Gulf for a long-term period (32-year) are used to describe and quantify the seasonal wave climate and trends. The model is forced by a wind reanalysis dataset and validated against a set of field measurements and altimeter data from various satellite missions. The results revealed the existence of a more energetic wave (higher Hm0 and larger TP) zone located at the southern regions of the Gulf that is linked to the predominant and stronger north-westerly winds. The wave heights and periods are intensified in winter (Hm0>2.7m and TP > 8s for the 99th percentile) followed by spring. The waves conditions are milder in autumn. The analysis of wave climate trends throughout the region clearly show an overall slight positive trend (0–0.2%/year) in mean Hm0, which is associated with long-term positive trends in wind speed. There is generally a positive trend in the mean significant wave height during winter (0–0.8%/year), spring (0–0.6%/year) and autumn (0–1.0%/year), and negative during summer (0–0.8%/year). The results indicate that the more statistically significant results are at the areas with larger magnitude of trends.