Will we lose all our beaches underwater as sea levels rise? Won’t it take years for new beaches to form?

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Will we lose all our beaches underwater as sea levels rise? Won’t it take years for new beaches to form?

In: Earth Science

22 Answers

Anonymous 0 Comments

Yes, but actually no. The rise will cover some current beaches. But it will take time, and much of the sand will be washed up on the new beach area. Eventually it will be so high that many miles of coastline will be underwater. Imagine the lower half of Florida underwater, so there will be much less actual beach

Anonymous 0 Comments

Yes and no. Or it’s complicated. It depends on the local geography and what humans do. Some areas will flood. Some areas will form new bays and estuaries. Take a look at how coastlines have changed in geologic time. A lot depends on what we do. We build sea walls and it changes the flow of water and sediments for large areas of coastline. We dredge rivers to make them deeper. Diapers an jetties all change the rate of sedimentation.

Anonymous 0 Comments

Your question implies that beaches as recreation are important to you.

In our lifetime “fun” beaches will remain with periodic issues of erosion, of more or less severity.

Our great-great-grandchildren will have an entirely different relationship with beach holidays.

So, yes, in the intermediate term [100 years], we are losing the typically understood holiday beach venues.

Yes, it will take millenia to re-draw the coast and establish beaches. This assumes we take explicit action to slow climate change.

If we don’t take action [and maybe if we do…the hour is late], we’re looking at inexorable Polar melt with a concomitant sea-level rise.

In this case, the loss of beach holidays is the smallest of our concerns.

Anonymous 0 Comments

Beaches will migrate uphill. Waves push sand up the slope, and then the draining water pulls some of it back. As the sea level increases, that’ll happen further inland than today.

And barrier islands will likewise migrate shoreward.

Anonymous 0 Comments

You need to keep in mind that sea level rise isn’t an immediate process. The most extreme rates are currently millimeters to centimeters per year. Wave action can likely move the sand around quick enough that your favorite beach isn’t gonna be swallowed by the sea. However local geology is a massive factor in this, and the rate of inland advance depends highly on the angle of the beach.

Anonymous 0 Comments

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Anonymous 0 Comments

Don’t think so. I don’t know much about this, except I was on a beach that had moved once. You can swim out 50m and find the remains of houses and a school that were built in the 60’s. The “ruins” are mostly just foundations and septic tanks now, and it otherwise looks like a normal beach.

So if that beach was fine with conquering a human settlement I assume others can do it too.

Anonymous 0 Comments

When Hurricane Irma hit the north shore of Cuba in September 2017 – specifically the resort area of Cayo Coco and surrounding islands – the beaches were completely washed away as waves pounded inland for several hundred meters. When I went to Cayo Coco in February 2018, some of the resorts were just beginning to reopen (having been rebuilding since the previous September), and far out from the shore, massive hydrovac ships were pumping sand back to the shoreline to reestablish the beaches. Many kilometers of beaches were rebuilt with 50-100 feet+ of new waterfront sand.

I would think that as water rises slowly, and infrastructure and buildings become old, damaged, or not worth saving, that there is a lot of private and government money ready to rebuild beaches at new sea levels to maintain waterfront holiday spots whenever that time comes.

Anonymous 0 Comments

Beaches are going to be the least of your worries. Food supplies are going to get hit hard. Coastal cities will suffer catastrophic water damage. Droughts will become commonplace. Large swaths of formerly fertile if not lush areas will turn into new deserts as it becomes too hot for vegetation to survive. Fires will devastate timber and wild lands.

Anonymous 0 Comments

I’m not sure I buy the “sand will be redeposited” theories.

What happens on all of the Southern California beaches? There are houses there. The ocean rises two feet and they are either gone or protected by a sea wall.

If the houses go away, the land is usually pretty flat. You’re not going to get a bunch of people to give up their houses so the beach in the middle can have a place to restore.

If you put up a a sea wall, there’s no beach.

That’s just SoCal but there are lots of places with similar geography.