Marine Heatwaves Study Based on Copernicus OSTIA L4 Satellite Derived Sea Surface Temperature and Geospatial Analysis in the Arafura Sea (1982-2024)
Attaqwa R., Maulana A., Saputri A.D., Harini S.H.N., Ramadhan D.A., and Helmi M.

Department of Oceanography, Faculty of Fisheries and Marine Science, Universitas Diponegoro, Indonesia

Abstract

Atmosphere and ocean interactions have driven significant rises in sea surface temperature (SST) across the Arafura Sea, Indonesia, exacerbated by extensive marine heatwaves (MHWs). Understanding these events is essential due to the region ecological and economic importance, especially for fisheries and coral ecosystems. This study aims to analyze the temporal and spatial characteristics of MHWs in the Arafura Sea between 1982 and 2024. This research is among the first to comprehensively examine MHWs in this region using a long-term SST dataset. We employed Hobday et al. hierarchical detection algorithm and utilized OSTIA L4 Copernicus Global Ocean Physics Reanalysis SST data (1982-2021) along with Near Real Time SST data (2022-2024). We identified 65 distinct MHWs events, accounting for 2,325 MHW days over the 42-year period. The most intense event occurred from 7 September to 29 November 2022 (84 days), with a peak anomaly of 2.26 degrees Celsius and an average intensity of 1.43 degrees Celsius. Spatially, MHWs frequency and duration peaked in the central and northern Arafura Sea, with coastal maximum intensities reaching 2.0&#8239-degrees Celsius. These results confirm an intensifying MHWs trend in the region. The findings are vital for advancing oceanographic knowledge, supporting marine resource management, and guiding coastal climate resilience strategies.

Keywords: Marine Heatwaves, Arafura Sea, Remote Sensing, Sea Surface Temperature, Geospatial Analysis

Topic: Topic B: Applications of Remote Sensing