February 12, 2025 – Coral reefs in the Gulf of Eilat/Aqaba experienced a surprising 3,000-year “shutdown” in growth, likely due to a temporary drop in sea level that may have been caused by global cooling, according to a new study by Hebrew University of Jerusalem researchers.

This phenomenon, detailed in Global Change Biology, is similar to other reef interruptions in Mexico, Brazil, and Australia and suggests a widespread environmental shift approximately 4,400 to 1,000 years ago during the late Holocene period. The study attributes this temporary “shutdown” to a combination of tectonic activity and glacio-eustatic sea-level changes. A temporary sea-level drop, possibly caused by a cooling event, exposed the reef and halted its growth.

Coral reefs are vital for marine biodiversity, playing a critical role in the oceanic carbon cycle and serving as natural barriers against coastal erosion and storm surges. However, their long-term sensitivity to temperature fluctuations, sea-level shifts, and anthropogenic influences remains poorly understood.

Despite the long pause, the reef eventually recovered, with coral species recolonizing from deeper coral communities, demonstrating their natural resilience. Nevertheless, researchers warn that today’s climate change, pollution, and ocean acidification pose far greater challenges, making conservation efforts more critical than ever to protect these vital marine ecosystems.

The study was led by Hebrew University Prof. Adi Torfstein of the Fredy & Nadine Herrmann Institute of Earth Sciences and Prof. Oren Levy from Bar-Ilan University, in collaboration with an international team of researchers.

“Understanding how reefs have responded to past sea-level changes helps us predict their future resilience and informs conservation strategies,” said Dr. Torfstein. “While our research shows that coral communities can recover after major disruptions, today’s climate crisis presents unprecedented challenges that demand urgent action.”

Supported by the Israel Nature and Parks Authority, this study enhances our understanding of coral reef dynamics and contributes to global efforts to protect these fragile marine ecosystems.

The research paper titled “Late Holocene ‘Turn-Off’ of Coral Reef Growth in the Northern Red Sea and Implications for a Sea-Level Fall” is now available in Global Change Biology and can be accessed here.

Researchers:
B. Feldman1, A. Torfstein2,3, M. O’Leary4, N. Simon Blecher1, R. Yam5, Y. Shaked3, A. Shemesh5, D. Huang6, O. Levy1,3
Institutions:
1.   Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University
2.   The Fredy and Nadine Herrmann Institute of Earth Sciences, The Hebrew University of Jerusalem
3.   Interuniversity Institute for Marine Sciences, Eilat, Israel
4.   School of Earth Sciences, University of Western Australia
5.   Department of Earth and Planetary Sciences, Weizmann Institute of Science
6.   Department of Biological Sciences, National University of Singapore