Climate extremes limiting the growth of East Asian mangroves for future nature-based solutions

Mangroves represent distinctive coastal ecosystems that offer ecological benefits, notably through their high carbon sequestration rates. East Asia is one of the northern distributional limits of global mangroves. While this region contains only a small fraction of the world’s mangrove coverage, its carbon sequestration potential and restoration capacity are highly significant. However, their resilience to extreme climate events remains uncertain, raising concerns about their long-term sustainability under future climate variability.

Here, we investigate the response of mangroves in East Asia to climate variability by employing the remote-sensing derived normalized difference vegetation index (NDVI) as a proxy for mangrove health, considering both simultaneous and time-lagged effects. We found East Asian mangrove growth has positive relations with temperature and solar radiation, particularly in cumulative anomalies on seasonal time scales. For example, winter temperature influences subsequent spring growth, and solar radiation around the summer–autumn transition affects mangrove growth during the autumn period.

These findings are extrapolated to future projections by the Earth system modelling to explore not only existing mangroves but also potential habitats. Compared with scenarios SSP1-2.6, SSP3-7.0 shows higher temperatures but lower solar radiation toward the end of the century, mainly due to stronger aerosol emissions under the fossil-fuel-dominated scenarios. While shifts in wintertime isotherms indicate northward expansion of mangroves under global warming, low solar radiation events associated with aerosol emissions in East Asia could remain a limiting factor for their growth, especially in SSP3-7.0.

This study underscores the importance of climate extremes in practical planning for future mangrove conservation, restoration, and migration, which are considered effective nature-based climate solutions. Our results indicate that while rising temperatures may facilitate mangrove expansion and enhanced productivity, growth may still be hindered by episodic reductions in solar radiation if anthropogenic drivers of climate change remain unmitigated. Balancing these opportunities and risks will require integrated, multidisciplinary approaches that account for both anthropogenic and natural climate dynamics.