West Coast
Half Moon Bay, CA. (Flickr)

CA - Sea level changes could drastically affect Calif. beaches by the end of the century

A new report finds that California could lose most of its beaches by the year 2100, due to rising sea levels. NPR's A Martinez goes to the beach to find out what can be done.


Imagine California without beaches.

SEAN VITOUSEK: We looked at future erosion potential going into about the year 2100, you know, and we found that depending on the sea level rise scenario, California might lose about a quarter to three-quarters of its beaches.

MARTÍNEZ: That is Sean Vitousek, a researcher for the U.S. Geological Survey based in Santa Cruz, Calif. He authored a study using satellite images going back decades, then combined those images with models of climate-crisis-driven sea level rise. Vitousek says it wouldn't take much rise to lose a lot of coastline.

VITOUSEK: The rule of thumb is basically for about every meter of sea level rise, you're probably going to get about 30 meters of coastal erosion happening. So when you get into three meters of sea level rise, you're talking almost 100 meters - you know, 300-plus feet of erosion under those large scenarios. Not to mention the flooding challenges that are also associated with sea level rise - you just have more severe and more frequent floods associated with waves.

MARTÍNEZ: Vitousek's study is a prediction of what may happen. And while he's confident in it, he admits having healthy skepticism is always important. So I got a second opinion. Because California losing 75% of its beaches - I mean, those numbers just can't be right.

KATHLEEN TRESEDER: Yeah, they look right. They're consistent with his previous study. He used a different approach. And so whenever we have two approaches like that that arrive at a similar conclusion, that makes me feel like the results are relatively robust. So I do believe it.

MARTÍNEZ: Kathleen Treseder studies and teaches climate change at the University of California, Irvine. I met her at Sunset Beach in Orange County. It's one of the places in Southern California that Vitousek says is most feeling the effects of coastal erosion. As we were standing on the sand on the edge of the Pacific Ocean, things kind of looked all right to me. There's a long row of what probably are very expensive places to live on either side of us. And people were hanging out, having fun in the sun. So I asked Treseder, why should they be worried?

TRESEDER: Well, because as we have the sea level rise - as you can see, this is a very shallow area. The sand doesn't go up uphill to the houses very steeply, right? So these houses are actually - it looks like within about 10 feet of the ocean right now. And so just from normal sea level rise, just without even any waves, you know, the waves should be lapping at their porches by the end of the century. But then when you add these big storm surges, that's just going to take out these homes. I mean, these homes were not designed to be battered by really severe waves.

MARTÍNEZ: Do you think that people who live here right now kind of realize that, or are they maybe putting it behind them or at the back of their minds as much as possible?

TRESEDER: I - well, looking here, there are a number of homes that are being renovated. There are some that clearly were renovated lately. I mean, if I were a homeowner, I wouldn't be doing that if I were worried about it. My guess is they probably don't realize.

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