Atmosphere-Ocean Coupled Variability in the Arabian/Persian Gulf

Fahad Al Senafi

doi:10.3389/fmars.2022.809355

Abstract

The Arabian Gulf comprises one of the world's most unique and fragile marine ecosystems; it is susceptible to the adverse effects of climate change due to its shallow depth and its location within an arid region that witnesses frequent severe atmospheric events. To reproduce these effects in numerical models, it is important to obtain a better understanding of the region's sea surface temperature (SST) variability patterns, as SST is a major driver of circulation in shallow environments. To this end, here, empirical orthogonal function (EOF) decomposition analysis was conducted to investigate interannual to multi-decadal SST variability in the Gulf from 1982 to 2020, using daily Level 4 Group for High Resolution SST (GHRSST) data. In this way, three dominant EOF modes were identified to contribute the Gulf's SST variability. Significant spatial and temporal correlations were found suggesting that throughout the 39-year study period, SST variability could be attributed to atmospheric changes driven by the El Nio-Southern Oscillation (ENSO), Atlantic Multi-decadal Oscillation (AMO), and Indian Ocean Dipole (IOD) climate modes. Spatial and temporal analyses of the dataset revealed that the average SST was 26.7°C, and that the warming rate from 1982 to 2020 reached up to 0.59°C/decade. A detailed examination of SST changes associated with heat exchange at the air-sea interface was conducted using surface heat fluxes from fifth generation (ERA5) European Centre for Medium-Range Weather Forecasts (ECMWF). Despite the SST warming trend, the accumulation of heat during the study period is suggesting that there was an overall loss of heat (cooling). This cooling reverted into heating in 2003 and has since been increasing.

Highlights

Owing to its strategic location and its susceptibility to extremely high temperatures and salinities (Johns et al, 2003; Khan et al, 2021), the Arabian Gulf is one of the most important, yet fragile, marine ecosystems on Earth
The Gulf daily sea surface temperature (SST) time series for the period of 1982 to 2020 revealed that the spatial period average was 26.7◦C (Figure 3A), and that it displayed a latitudinal gradient of cooler temperatures from south to north
The Gulf ’s maximum SST (36.7◦C) was recorded on July 1996 in the vicinity of Makasib Island, which is located between Qatar and the United Arab Emirates (UAE; Figure 3C)

Summary

Introduction

Owing to its strategic location and its susceptibility to extremely high temperatures and salinities (Johns et al, 2003; Khan et al, 2021), the Arabian Gulf (hereafter Gulf) is one of the most important, yet fragile, marine ecosystems on Earth. Increasing water temperatures driven by global warming, as well as contaminants (oil spills, waste waters, and industrial waste) (Uddin et al, 2021; StöfenOBrien et al, 2022), have severely affected and degraded the Gulf ’s marine ecosystems, such as its sabkhas, mudflats, mangrove swamps, sea grasses, and coral reefs (Burt et al, 2011; Vaughan et al, 2021). These ecosystems support various endangered marine species, such as dugongs and turtles (Sale et al, 2010). In relation to the preservation of climate balance in the Gulf, coupled atmosphere-ocean dynamics play a major role in determining regional and global

Methods

Results

Conclusion