Climate Change Multiplies Flood Risk on Cape and Islands | WCAI

Climate Change Multiplies Flood Risk on Cape and Islands

Jul 17, 2020

By 2050, communities on the Cape and Islands could see 35 to 135 days a year of coastal flooding as a result of climate change, according to a new report from the National Oceanic and Atmospheric Administration (NOAA). 


In the agency’s annual report, scientists monitor high-tide or “sunny day” flooding — flooding when no storm occurs, but water rises about two feet above the typical daily high tide — in 98 communities, including Nantucket and Woods Hole. 

 

 

While Woods Hole and Nantucket each saw several days of sunny day flooding in 2019, they’re expected to see no more than three to seven days of it in 2020. But by 2050 that could increase to 35 to 135 days a year. By 2050, Boston could see as many as 95 days of sunny day flooding each year.

 

“This range is a range that’s considered likely under continued emissions as well as reduced emissions,” said William Sweet, NOAA oceanographer and lead author on the report. “It’s sort of the trajectory we’re on.” 

 

The damage from high-tide flooding could affect local economies, tourism, and crucial infrastructure like septic and freshwater systems. 

 

The reason for the increase is directly connected to climate change. 

 

As oceans warm and glaciers melt, sea levels are rising. Floods that used to occur only during storms now will happen more often, such as during a full moon or king tide, or simply with a change in winds or currents.

 

“If certain areas are getting wet during storms or more typical events like king tides, they’re only going to get worse in the future,” Sweet said.  “And areas that may not seem susceptible now will become so in the next several decades.”

 

The East and Gulf Coasts seem to be the regions that are most susceptible to the changes that are occurring. 

 

Communities up and down these coasts, Sweet said, need to recognize vulnerable infrastructure before more frequent and severe floods occur.

 

“Knowing this should help give at least a little bit of guidance and anticipation on how to adapt and react appropriately to minimize the effects moving forward,” he said. 

 

The damage from this flooding will fundamentally change coastal living, but Sweet remains hopeful.  

 

“It’s not to say we won’t live harmoniously with new sea level rises," he said. "We just need to be aware that change is at hand and recognize that the tide’s going to go where the tide’s going to."