Thresholds of mangrove survival under rapid sea level rise
© Reinhard Dirscherl/Getty
Mangrove trees could start dying off within three decades if sea level rise continues to accelerate.
Many coastlines around the world are protected by mangrove forests, which reduce the risk of flooding and store a lot of carbon dioxide. How mangroves will respond to the quickening pace of rising seas is unclear.
A team that included researchers from Nanyang Technological University, Singapore, used sediment records to study mangrove growth at 78 sites worldwide from 10,000 to 7,000 years ago, when melting glaciers pushed sea level rise above today’s rate.
They then modelled growth under two climate scenarios and found that once sea level starts rising faster than 6.1 millimetres per year, as is predicted by 2050 with high emissions of greenhouse gases, mangroves cannot keep pace and begin to die back or retreat inland.
Slowing sea level rise by reducing emissions is essential for protecting coastal settlements and ecosystems in the tropics.
- Science 368, 1118–1121 (2020). doi: 10.1126/science.aba2656