California's Coastal Marshes Face Extinction By 2110

Climate change and coastal development are combining to stamp out important ecological landscapes.

1 minute read

March 2, 2018, 12:00 PM PST

By Elana Eden


San Luis Obispo County

Los Osos, in San Luis Obispo County, California. | joojoob27 / Shutterstock

Ninety percent of California's wetlands have been lost to development, researchers say—and 100 percent of the marshes remaining could disappear by the end of the century if greenhouse gas emissions don't decrease.

The marshes would have a shot at survival if they could migrate inland, but coastal development patterns are boxing them in, a USGS researcher told KPCC. USGS and UCLA co-authored the new study that calculated the threat to California's coastal ecology.

Besides providing important habitats for millennia, marshes "serve key functions related to the health of the planet," KPCC's Jacob Margolis explains. Their decay could result in even more emissions, as well as erosion and water pollution.

They store carbon, which will be released as they begin to die off. They are barriers to storm surges that protect against erosion. They act as catches for debris that make their way down from the hills after wildfires. And they filter polluted water and sediment that flows from our cities towards the ocean, keeping our seas a bit cleaner.

Further explanation, and a picture slideshow, are included in the full story.

Wednesday, February 21, 2018 in KPCC

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