Rising sea levels threaten Everglades
Climate change making ecosystem less resilient to events like hurricanes
As residents of the Southeast are returning home and assessing the damage left by Hurricane Irma, Florida scientists are anxiously waiting to evaluate the storm’s impact on one of the state’s most valuable — and vulnerable — ecosystems: the Everglades.
Already threatened by the continuous progression of sea-level rise — which pumps damaging salt water into the habitat, jeopardizing groundwater resources, contributing to erosion and threatening wildlife and vegetation — some scientists worry that the weakened Everglades are becoming less resilient to disruptive events like hurricanes. The issue is a prime example of the way climate change can render ecosystems more vulnerable to even natural disturbances.
Indeed, it’s an issue that President Barack Obama chose to highlight two years ago during his last term. On a visit to Everglades National Park in April 2015, timed to coincide with Earth Day, Obama emphasized the growing threat of climate change and pointed to the impact of the rising seas in Florida as an example.
“Climate change is threatening this treasure and the communities that depend on it, which includes almost all of South Florida,” he said in a speech delivered at the entrance of Everglades National Park. “And if we don’t act, there may not be an Everglades as we know it.”
Everglades National Park consists of about 1.5 million acres, or more than 2,300 square miles, of wetland area, containing pine woodlands, saw grass marshes and extensive mangrove forests, which help to naturally build up the land and buffer the coast against the rising seas. It’s home to a diverse variety of wildlife — including crocodiles and alligators, as Obama pointed out in his speech — and it’s part of the freshwater system that feeds South Florida’s Biscayne Aquifer, a source of drinking water for millions of people.
Hurricanes, in and of themselves, are not necessarily devastating events for the Everglades, according to Harold Wanless, an expert on coastal geology at the University of Miami. They have long been a natural and common occurrence in South Florida. They can even sometimes benefit the landscape by throwing mud onto the coast and helping to build up the land.
Over the last century, however, sea-level rise — accelerated by human-induced global warming — has begun to degrade the Everglades by allowing salt water to seep into the system, scientists say. This is bad news for the freshwater plants and animals that live there, but it’s also a major threat to South Florida’s drinking water supplies.