Fewer cold snaps: Mangroves head north

Heading north

Florida’s mangroves are expanding northward, but not because the weather is warmer on average. The important factor is fewer cold snaps — days when the temperature falls to 25 F or less, which is the mangrove’s survival limit.

Mangrove forests have been expanding northward along the Atlantic coast of Florida for the last few decades not because of a general warming trend, but likely because cold snaps there are becoming a thing of the past. That surprising finding, reported by a team of ecologists in the Proceedings of the National Academy of Sciences, provides a new and unique illustration of the speed and scale on which alterations in climate extremes have affected crucial ecosystems. More.