An international team of scientists from Australia, Singapore, the United States, and other nations studied how mangroves, tidal marshes, and coral islands endure rising seas and warming oceans. Their assessments indicate that warming the atmosphere by more than 2 °C above pre-industrial levels would drive flooding and widespread die-off across more than 1,500 coastal ecosystems globally. The work appears in the journal Nature.
Mangrove forests and coastal wetlands play a vital role in climate protection because they absorb substantial amounts of greenhouse gases from the air, storing carbon in their soils and vegetation for long periods.
To derive their conclusions, the researchers gathered data from 190 mangrove sites, 477 tidal marshes, and 872 coral reef island systems around the world. They then ran computer simulations to project how these ecosystems would respond to different sea-level and climate-change scenarios over time.
The analyses show that most coastal swamps, mangrove forests, and coral reefs can withstand the current pace of landward sea intrusion, measured at about 2–4 millimeters per year. Yet if global temperatures rise beyond 2 °C, the rate of sea-level increase could climb to 7–8 millimeters annually. In such a scenario, the study estimates a 90% chance that most mangroves and tidal marshes would be overwhelmed, with coral reefs facing a 67% likelihood of complete submergence in places.
Even at lower sea-level rise rates of roughly 4–5 millimeters per year, the projected losses of mangroves and tidal wetlands would be substantial, underscoring the fragility of these habitats under accelerated warming.
The researchers call on governments and international organizations to take decisive action to safeguard coastal ecosystems by expanding protected areas, enforcing sustainable coastal development, and prioritizing restoration efforts that bolster resilience to rising seas.
Looking ahead, the findings emphasize the urgency of integrated coastal management that aligns climate mitigation with habitat protection. Protecting mangroves, marshes, and reefs not only preserves biodiversity but also helps communities adapt to climate-change impacts by sustaining fisheries, buffering storms, and maintaining carbon storage networks. This holistic view reinforces the value of proactive policy and long-term stewardship to safeguard coastal health for future generations (Nature).