New study reveals that corals in the Gulf of Aqaba have withstood four consecutive and intensifying marine heatwaves, including the world’s most extreme 2024 event, without suffering mass bleaching — a resilience unmatched elsewhere. This is important because coral reefs globally are collapsing under rising ocean temperatures, threatening ecosystems and human livelihoods. The Gulf of Aqaba may represent one of the planet’s last natural refuges for reef survival, offering a crucial model for understanding resilience and underscoring the urgency of protecting this unique ecosystem before even it reaches its limits. New study reveals resilience of Red Sea corals in the face of intensifying climate threats.
A new study led by Phd. student Na'ama-Rose Kochman and Prof. Maoz Fine of the Hebrew University’s Institute of Life Sciences and the Interuniversity Institute for Marine Sciences in Eilat, has uncovered extraordinary resilience among corals in the Gulf of Aqaba (GoA), raising hopes for the future of this globally-significant coral reef amid worsening climate change.
The findings, published in Science of the Total Environment, show that GoA corals endured four consecutive summers of intensifying marine heatwaves, including a record-breaking 2024 event that lasted 113 days with sea surface temperatures soaring to 32.6°C — 3.4°C above average and generating 30 Degree Heating Weeks (DHWs), the highest thermal stress recorded globally last year.
Key Findings
- Survival through record stress: Five coral species survived the world’s most extreme 2024 heat event without mass bleaching.
- Energy resilience: Corals maintained stable energy reserves, with higher symbiont carbohydrates in 2024 compared to previous years.
- Species responses: Porites showed metabolic stability, while Cyphastrea experienced stress but recovered within months.
- A climate refuge under pressure: Despite remarkable tolerance, sporadic shallow bleaching suggest the Gulf’s may be reaching its limit.
“While nearly half of reef-building corals worldwide face the risk of extinction, our study shows that the Gulf of Aqaba remains one of the last strongholds of reef survival,” said Na'ama-Rose Kochman. “But even this refuge is not immune to the accelerating pace of climate change and local pollution.”
Prof. Fine added: “These results highlight both the resilience and the fragility of coral ecosystems. They underscore the urgent need for regional conservation policies to safeguard what could be the world’s last thriving coral reef.”
Coral reefs are biodiversity hotspots that sustain millions of livelihoods, from fisheries to coastal protection. Yet marine heatwaves — prolonged periods of unusually warm sea surface temperatures — are now one of the primary drivers of coral mortality worldwide.
The resilience of the Gulf of Aqaba corals offers a rare glimmer of hope. Scientists emphasize, however, that without rapid climate action and local protections, even this stronghold may not withstand future warming.
Coral Reef | Credit: Maoz Fine
The research paper titled “ Gulf of Aqaba as a thermal refuge: Insights from four years of intensifying marine heatwaves” is now available in The Science of the Total Environment and can be accessed at https://doi.org/10.1016/j.scitotenv.2025.180463 .
Researchers:
Na’ama-Rose Kochman1,2, Maoz Fine1,2
Institutions:
- Department of Ecology, Evolution and Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem
- The Interuniversity Institute for Marine Sciences, Eilat
For a century, the Hebrew University of Jerusalem has been a beacon for visionary minds who challenge convention and shape the future. Founded by luminaries like Albert Einstein, who entrusted his intellectual legacy to the university, it is dedicated to advancing knowledge, cultivating leadership, and promoting diversity. Home to over 23,000 students from 90 countries, the Hebrew University drives much of Israel’s civilian scientific research and the commercialization of technologies through Yissum, its tech transfer company. Hebrew University’s groundbreaking contributions have been recognized with major international awards, including nine Nobel Prizes, two Turing Awards, and a Fields Medal. Ranked 88th globally by the Shanghai Ranking (2025), Hebrew University marks a century of excellence in research, education, and innovation. To learn more about the university’s academic programs, research, and achievements, visit the official website at http://new.huji.ac.il/en.