Beaches and swamps have a place in the future of a coastal city, according to experts.
In the US, a recent study by the US National Oceanic and Atmospheric Administration found that coastal communities are being inundated with more than 10m tons of sediment a year, and in many places are expected to become uninhabitable by the end of this century.
It is estimated that up to one-fifth of the world’s wetlands could be wiped out by 2040.
The National Marine Fisheries Service predicts that if the global population continues to rise at the current rate, wetlands will be lost in the US and Europe by the middle of the century.
The scientists say the current trend will be exacerbated by the impact of climate change.
The US government has set a target of reducing greenhouse gas emissions by 28% by 2050.
The study said that in areas of the US that were already flooded with sediment, the rate of sediment accumulation could exceed that of wetlands by the mid-2030s.
The team from the University of California, Irvine found that while wetlands are already in the process of being inundating coastal areas, the future is not looking good.
“It’s pretty scary to think about what we could do,” Dr Lorna Cottle said.
“The number of wetlands is increasing, and the impact is going to get even bigger.”
The researchers believe that as global warming increases the risk of flooding, they could see areas of California that were previously protected by wetlands disappear in the coming decades.
Coastal wetlands in particular are vulnerable to erosion, and will need to be protected in the face of rising seas, the researchers say.
The authors say the risk for the US is “potentially greater” if coastal wetlands are left to deteriorate due to climate change, and that “there is a lot of room for further improvement in wetlands protection in the United States”.
The research team, which includes researchers from the United Nations Environment Programme, the University at Albany and the United Kingdom’s Environment Agency, was able to track the rates of sediment deposition and the thickness of the sediment in wetlands over a five-year period.
The sediment deposited in wetlands is the main component of coastal erosion, Dr Cottles research team found.
“If we want to reduce coastal erosion rates, we need to work together to reduce the amount of sediment that is being deposited,” she said.
The research suggests that if we can prevent coastal wetlands from degrading due to human activities, the area of land that is protected could increase by up to 10% over the next five years.
It also suggests that “we can mitigate some of the damage that could occur from climate change”, Dr Cattles said.