| dc.description.abstract | Ocean warming and acidification, driven by increasing atmospheric CO2 levels, pose significant threats to coral reef ecosystems, resulting in coral bleaching and significant biogeochemical and socioeconomic consequences. While some research has explored these phenomena in the Philippines and its surrounding areas, there remains a critical gap in large-scale assessments integrating marine heatwaves (MHWs), ocean acidification (OA), and coral bleaching, using the index Degree Heating Weeks (DHW). This study conducted a comprehensive evaluation of MHWs, OA, and coral bleaching indices in the surrounding waters of the Philippines from 1985 to 2022, utilizing satellite and reanalysis data. Twelve coral reef points were selected to further examine these phenomena and their effects on coral reefs. The study area was divided into three groups, providing a detailed examination of the spatiotemporal dynamics of these stressors in the north, west, and east of the Philippines. The study identified that June is the most vulnerable month for Group I to warming and for Group II to acidification. Based on the MHW indices and shifts in the patterns of the leading mode of EOF of SST, pH, and spCO2, the Davao Oriental (Point L) is the most vulnerable coral reef point for the Philippines, followed by the coast of Lingayen Gulf (Point E). Point L achieved the highest average MHW duration with 90.5 days/ times in 2020, while Point E experienced the maximum total MHW days in 2022 with 293 days. The highest DHW value reached by Point E was 8.94°C-weeks in July and August 2022. Additionally, the combined effect of climate indices such as ENSO and PDO affects the SST anomaly and MHW occurrences in the study area. The identification of high-risk and vulnerable coral reef regions, along with insights into the complex interactions between stressors, provides valuable guidance for marine researchers and decision-makers in implementing targeted conservation and mitigation measures. | en_US |