Tropical wetlands provide storm protection that saves thousands of lives and more than $600bn each year, an Australian-linked world-first study has found.
“It’s vitally important because around the world the area covered by wetlands is reducing and as we keep destroying our wetlands, we are putting more and more people at risk,” Dr Diane Jarvis from James Cook University said.
Jarvis was part of a team of 12 scientists that has examined more than 1,000 hurricanes and cyclones responsible for deaths or damaged property since 1902.
An average cyclone season in Australia’s north sees about 11 tropical systems eventuate, four of which cross the coast.
Queensland continues to pour recovery money into areas devastated by Tropical Cyclone Debbie, with $6m most recently allocated by government to rebuild an entertainment centre at Proserpine.
Fourteen people died and about 2,300 homes were damaged as the second most expensive cyclone in Australia’s history – behind Darwin’s Tracy in 1974 – smashed into the Whitsunday region in March 2017 with 260km/h winds.
Total losses reached almost $1.8bn with 75,000 insurance claims lodged.
Queenslanders also received a battering from cyclones Nathan and Marcia in 2015.
Jarvis and her colleagues looked at land use data for 71 countries that showed any wetlands in the path of storms. These included mangroves, estuaries, swamps and mudflats, which she said absorb the energy of extreme storms in ways open water and solid land can’t.
The results showed wetlands offered significant protection by reducing the speed and turbulence of extreme storms and providing natural barriers when storm surges hit, the researcher said.
“When a storm makes landfall, if it crosses a wetland, that absorbs some of the force of the storm.”
While there have been similar studies in Australia, the US and China, it’s the first time scientists have proved the protective properties of wetlands globally.
The researchers found the 40m hectares of wetlands in storm-prone areas globally protected about 4,620 lives annually and prevented damage worth $603bn.
About half of all wetlands globally have been destroyed since 1900, according to Jarvis.
About 700 million people live at less than 10 metres above sea level. The effects of climate change include a predicted increase in the frequency and intensity of tropical cyclones.
The paper was published in the journal Global Environmental Change.