Can We Rely on Mangroves to Provide a Line of Defense against Sea Level Rise Flooding?

One of the greatest challenges involved in combatting sea level rise flooding is finding solutions that will stand the test of time. Some coastal communities have been seeking natural solutions, such as sand dunes, wetlands and native vegetation, to hold back ever-higher tides and storm surges. Planners recognize the ability of natural ecosystems to self-regulate and adjust to sea water as it exerts pressure to march inland.

In the U.S., some southern Atlantic and Gulf Coast communities have been including mangroves in their action plans. They’re counting on the thick, leafy forests that thrive in shallow coastal waters to not only absorb and store some of the carbon released into the atmosphere by the burning of fossil fuels that’s driving global warming but to act as a buffer against storm surges and higher tides. They also hope to benefit from the mangroves ability to capture sediments and build land when the seas are trying to erode it away.

The idea sounded great until a recent study led by Macquarie University in Australia found that unless humans reduce the release of greenhouse gases, the seas will soon rise at a faster pace than the mangroves can accommodate. With sea level rise accelerating, due to ocean expansion and the ever-quickening pace of ice melt in Greenland and Antarctica, the mangroves could start to disappear within the next thirty years.

Unfortunately, real estate alone won’t pay the price when mangroves are gone. Mangroves provide a valuable nursery for birds, fish and other organisms. Their loss will endanger whole ecosystems.