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Abstract In light of rapid environmental change, quantifying the contribution of regional‐ and local‐scale drivers of coral persistence is necessary to characterize fully the resilience of coral reef systems. To assess multiscale responses to thermal perturbation of corals in the Coral Triangle (CT), we developed a spatially explicit metacommunity model with coral–algal competition, including seasonal larval dispersal and external spatiotemporal forcing. We tested coral sensitivity in 2,083 reefs across the CT region and surrounding areas under potential future temperature regimes, with and without interannual climate variability, exploring a range of 0.5–2.0°C overall increase in temperature in the system by 2054. We found that among future projections, reef survival probability and mean percent coral cover over time were largely determined by the presence or absence of interannual sea surface temperature (SST) extremes as well as absolute temperature increase. Overall, reefs that experienced SST time series that were filtered to remove interannual variability had approximately double the chance of survival than reefs subjected to unfiltered SST. By the end of the forecast period, the inclusion of thermal anomalies was equivalent to an increase of at least 0.5°C in SST projections without anomalies. Change in percent coral cover varied widely across the region within temperature scenarios, with some reefs experiencing local extinction while others remaining relatively unchanged. Sink strength and current thermal stress threshold were found to be significant drivers of these patterns, highlighting the importance of processes that underlie larval connectivity and bleaching sensitivity in coral networks.
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This content will become publicly available on April 28, 2026
Physical Connectivity in the Wider Caribbean Region
Abstract Marine ecosystems in the wider Caribbean region (WCR) are biodiversity hotspots. They include coral reefs and provide critical societal benefits, yet climate change, pollution, and overfishing are threatening them. Marine ecosystem protection and restoration require understanding connectivity. Fish and coral larvae are actively exchanged across connected areas and larval transport promotes the replenishment of new healthy individuals after damaging events. Connectivity is dynamic and modulated by climate variability, but its evaluation with traditional tools remains elusive over spatio‐temporal scales of climate interest. Here machine learning helps exploring large‐scale connectivity in the WCR over nearly three decades. ENSO exerts the largest influence on the overall connectivity, with enhanced longitudinal connectivity in El Niño years. By combining connectivity with climate variability and thermal stress metrics, it is found that connectivity does not improve recovery potential in the WCR, in striking contrast with prior results for the tropical Pacific.
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- Award ID(s):
- 2232440
- PAR ID:
- 10615709
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 8
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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