Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines

The coral reefs in the Philippines are facing an unprecedented crisis. This study, based on a comprehensive analysis of marine heatwaves (MHWs), degree heating weeks (DHWs), and ocean acidification (OA) indices derived from satellite observations and reanalysis data, reveals how thermal stress and O...

Full description

Saved in:
Bibliographic Details
Main Authors: Rose Angeli Tabanao Macagga, Po-Chun Hsu
Format: Article
Language:English
Published: MDPI AG 2025-03-01
Series:Remote Sensing
Subjects:
Online Access:https://www.mdpi.com/2072-4292/17/6/1048
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850088410607255552
author Rose Angeli Tabanao Macagga
Po-Chun Hsu
author_facet Rose Angeli Tabanao Macagga
Po-Chun Hsu
author_sort Rose Angeli Tabanao Macagga
collection DOAJ
description The coral reefs in the Philippines are facing an unprecedented crisis. This study, based on a comprehensive analysis of marine heatwaves (MHWs), degree heating weeks (DHWs), and ocean acidification (OA) indices derived from satellite observations and reanalysis data, reveals how thermal stress and OA have progressively eroded coral ecosystems from 1985 to 2022. This study analyzed 12 critical coral habitats adjacent to the Philippines. The monthly average sea surface temperature (SST) in the study area ranged from 26.6 °C to 29.3 °C. The coast of Lingayen Gulf was identified as the most vulnerable coral reef site in the Philippines, followed by Davao Oriental and Polillo Island. The coast of Lingayen Gulf recorded the highest total MHW days in 2022, amounting to 293 days. The coast of Lingayen Gulf also reached the highest DHW values in July and August 2022, with 8.94 °C weeks, while Davao Oriental experienced the most extended average duration of MHWs in 2020, lasting 90.5 days per event. Large-scale climate features such as the El Niño–Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) significantly influenced the study area’s SST anomalies and MHW events. High-risk coral bleaching periods, such as 1988–1989, 1998–1999, 2007–2008, and 2009–2010, were characterized by transitions from El Niño and positive PDO phases, to La Niña and negative PDO phases. However, since 2015, global warming has led to high cumulative heat stress without specific climate background patterns. We propose a Coral Marine Environmental Vulnerability Index (CoralVI) to integrate the spatiotemporal dynamics of warming and acidification and their impacts on coral habitats. The data show a rapid increase in the marine environmental vulnerability of coral habitats in the Philippines in recent years, extending to almost the entire coastline, posing significant threats to coral survival.
format Article
id doaj-art-323d34454aaf4fbfaa1049ae56f6d84b
institution DOAJ
issn 2072-4292
language English
publishDate 2025-03-01
publisher MDPI AG
record_format Article
series Remote Sensing
spelling doaj-art-323d34454aaf4fbfaa1049ae56f6d84b2025-08-20T02:43:02ZengMDPI AGRemote Sensing2072-42922025-03-01176104810.3390/rs17061048Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the PhilippinesRose Angeli Tabanao Macagga0Po-Chun Hsu1Center for Space and Remote Sensing Research, National Central University, Taoyuan 320, TaiwanCenter for Space and Remote Sensing Research, National Central University, Taoyuan 320, TaiwanThe coral reefs in the Philippines are facing an unprecedented crisis. This study, based on a comprehensive analysis of marine heatwaves (MHWs), degree heating weeks (DHWs), and ocean acidification (OA) indices derived from satellite observations and reanalysis data, reveals how thermal stress and OA have progressively eroded coral ecosystems from 1985 to 2022. This study analyzed 12 critical coral habitats adjacent to the Philippines. The monthly average sea surface temperature (SST) in the study area ranged from 26.6 °C to 29.3 °C. The coast of Lingayen Gulf was identified as the most vulnerable coral reef site in the Philippines, followed by Davao Oriental and Polillo Island. The coast of Lingayen Gulf recorded the highest total MHW days in 2022, amounting to 293 days. The coast of Lingayen Gulf also reached the highest DHW values in July and August 2022, with 8.94 °C weeks, while Davao Oriental experienced the most extended average duration of MHWs in 2020, lasting 90.5 days per event. Large-scale climate features such as the El Niño–Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) significantly influenced the study area’s SST anomalies and MHW events. High-risk coral bleaching periods, such as 1988–1989, 1998–1999, 2007–2008, and 2009–2010, were characterized by transitions from El Niño and positive PDO phases, to La Niña and negative PDO phases. However, since 2015, global warming has led to high cumulative heat stress without specific climate background patterns. We propose a Coral Marine Environmental Vulnerability Index (CoralVI) to integrate the spatiotemporal dynamics of warming and acidification and their impacts on coral habitats. The data show a rapid increase in the marine environmental vulnerability of coral habitats in the Philippines in recent years, extending to almost the entire coastline, posing significant threats to coral survival.https://www.mdpi.com/2072-4292/17/6/1048Philippinesmarine heatwavesocean acidificationPacific Decadal OscillationEl Niño–Southern Oscillation
spellingShingle Rose Angeli Tabanao Macagga
Po-Chun Hsu
Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines
Remote Sensing
Philippines
marine heatwaves
ocean acidification
Pacific Decadal Oscillation
El Niño–Southern Oscillation
title Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines
title_full Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines
title_fullStr Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines
title_full_unstemmed Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines
title_short Spatiotemporal Dynamics of Marine Heatwaves and Ocean Acidification Affecting Coral Environments in the Philippines
title_sort spatiotemporal dynamics of marine heatwaves and ocean acidification affecting coral environments in the philippines
topic Philippines
marine heatwaves
ocean acidification
Pacific Decadal Oscillation
El Niño–Southern Oscillation
url https://www.mdpi.com/2072-4292/17/6/1048
work_keys_str_mv AT roseangelitabanaomacagga spatiotemporaldynamicsofmarineheatwavesandoceanacidificationaffectingcoralenvironmentsinthephilippines
AT pochunhsu spatiotemporaldynamicsofmarineheatwavesandoceanacidificationaffectingcoralenvironmentsinthephilippines