MIAMI — Florida's mangroves are moving further up the state's east coast, the latest indicator of global climate change.
Florida's Atlantic coast gained more than 3,000 acres of mangroves in the past three decades. That's according to new research published in the Proceedings of the National Academy of Sciences journal, the Miami Herald reports.
Scientists documented the mangrove growth by looking at satellite images from 1984 to 2011. Mangrove coverage doubled in the area between Cape Canaveral and St. Augustine.
Brown University postdoctoral researcher Kyle Cavanaugh said that while there are examples of climate changing having a negative impact, this could be different. The mangroves are replacing salt marshes, but both are important and highly productive coastal systems.
"The question we have to answer," Cavanaugh said, "is what do these changes mean to Florida's ecosystem? I think we'll find that they are not cause for alarm."
The researchers examined several possible explanations and concluded a decrease in the number of hard freezes were the likely factor behind the mangroves' push up the coast. Cold snaps of 25 degrees or less halt the growth of mangrove forests, and with fewer hard freezes, they expanded into new areas, the scientists found.
In Titusville, there were an average of 1.2 fewer days per year with extreme-cold temperatures between 2006 and 2011 than between 1984 and 1989. Similar findings were found in other cities.
The scientists are examining mangrove movement in other parts of the world as well, including Florida's Gulf Coast.
"There are mangrove forests all over the globe that are pushing up on the limits of salt marshes," Cavanaugh said. "It's a complex situation that we'll continue to be looking very closely at."