Influence of climate variability on wind‐sea and swell wave height extreme over the Indo‐Pacific Ocean

Abstract

In the Indo-Pacific Ocean (IPO), extreme significant wave heights (SWHs) can substantially induce coastal erosion, flooding, and devastating impacts on coastal livelihoods. This study examines the seasonal influence of the El Niño-Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), Southern Annular Mode (SAM), and Pacific North American (PNA) pattern on extreme windwave parameters. The climatic extremes are calculated utilizing ERA5 reanalysis datasets from 1979 to 2019 and a nonstationary generalized extreme value distribution. Significant increases in extreme wind-sea (Hmax) and swell SWH (Hmax Sw ) response to ENSO occur over the northeast North Pacific (NP) during December-February (DJF) and western NP during June-August (JJA).The PNA influence exhibits a similar pattern to ENSO during DJF yet is inactive in JJA. Hmax and Hmax Sw responses to the IOD during September-November (SON) include significant increases over the western Pacific, southern Indian Ocean (IO), and southwest tropical IO, yet decreases over the central tropical IO. The Hmax Sw response to the SAM is larger than that for Hmax over the southern IPO during DJF, which extends toward the eastern Pacific in March-May (MAM). Overall, extreme wind-sea and swell parameter responses are found to be associated with sea level pressure (SLP) and SLP gradients. K E Y W O R D S climate variability, generalized extreme value (GEV) distribution, Indo-Pacific Ocean, wind-sea and swell SWH

Historical change and variability of spectral wind wave climate in the New York Bight

“…Previous studies such as Kumar et al (2022) recognized and quantified climate index influence on swells and wind seas. The present study identified seasonal climate index correlation with wave family wave heights in the study area.…”

A Systematic Review of Oceanic-Atmospheric Variations and Coastal Erosion in Continental Latin America: Historical Trends, Future Projections, and Management Challenges

“…During December-January season, higher atmospheric pressures at high and low latitudes, especially on the coasts of the Eastern Pacific, reflect this trend, affecting wind conditions and leading to extreme waves. However, during the El Niño phase of this season, alterations in atmospheric circulation weaken pressure gradients in the southeastern Pacific Ocean region, potentially due to SAM's influence on the position and intensity of the subtropical and Polar Jet Streams in the southern hemisphere [46,47]. Variations in the subtropical Jet Stream may also affect precipitation patterns and cold front propagation in southern Brazil [48].…”

“…Additionally, an analysis of global climate patterns from 1979 to 2019 reveals the significant influence of swell waves in the eastern equatorial region of the Pacific Ocean. From December to February, there is a notable contribution of swells observed across a broad band spanning from the northeastern equatorial Pacific Ocean, between latitudes 30° N and 30° S. This region experiences a distinct rise in wave height, generating areas potentially dominated by swells, with extreme wave height exceeding >2.1 m due to the North Pacific and East Pacific trade winds [47]. Global climate patterns and climate teleconnections also play a crucial role in wave system variability.…”

“…• Waves reaching heights up to 2.00 m during the months of December to February, generated by westerly winds in the North Pacific and easterly trade winds between latitudes 30° N and 30° S in the eastern equatorial Pacific Kumar et al, 2022 [47] • Increase in wave height from the West and Southwest in Costa Rica has led to mangrove loss due to sediment modification towards a sandier and less silty composition.…”