Fast Company

Rapid Sea Level Rise Could Change 100-Year Storms Into Every Year Storms

One-tenth of an inch of water doesn't seem like much, but as the oceans rise that much each year, they could displace 150 million people around the world and drastically increase the damage done by flooding.


One tenth of an inch per year. That is the number that could lead to eventual flooding of some of the world's largest coastal cities. The slow but steady sea level rise off the coasts of Galveston, New York, Baltimore, San Francisco and many other cities hint at the warming world we'll inhabit by the end of the century. Although uncertainties remain about the exact magnitude and speed of future changes, satellites and tide gauges both agree that sea levels have risen worldwide by about 5 to 9 inches during the last century.

Since no one has been standing around measuring each tide since 200 BCE, scientists used fossils of microscopic algae called foraminifera of coastal salt marshes in North Carolina to track rising sea levels. Their carbon-dated results show ocean levels remained remained relatively stable during the last 2,000 years, rising only about 1/50 inch annually during a 400-year period. But in the late 1800s--right around the industrial revolution--that rate took off. Today, seas are rising about one-tenth of an inch each year, and it has been accelerating even since the 1960s.

Fractions of an inch might not sound like much, but the Organization for Economic Co-operation and Development figures at least 150 million people and trillions of dollars in property will be standing in the way of severe coastal flooding by 2100, mostly in the developing countries of Asia (although Miami made the top 10 list). While cities will not be fully inundated, they will be much more vulnerable to coastal floods and storms, and demand pricey counter measures such as the $1.2 billion the Dutch plan to spend annually on flood control.

If climate models are right--and the study reinforces the results of existing temperature and sea-level simulations--then the oceans could surge more than three feet by the end of the century, making once-a-century storms into a nearly annual occurrence. New York, along with much of the Atlantic seaboard, could experience routine flooding, including large parts of Queens and Brooklyn. The effects are already being felt in places like low-lying Bangladesh, and the low-lying Pacific islands where climate refugees are moving to higher ground.

[Image: USGS's Flickr stream]

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  • ClimateWarrior

      Looks like you don't know what you are talking about.  Meteorologist DOES NOT create climate change models.  The ones who makes them are called "Climatologist."  Maybe, you should educate yourself more by starting a research yourself.  No?

  • pvansickel

    Do you not know that the climate change models have been completely debunked?  They were specifcally designed to show a hockey stick no matter what the actual data.  Do some real research on what real meterolgists are saying rather then the Al Gore propaganda. 

  • Andrew Krause

    At the altar of Anthropogenic Global Warming, such talk is still heresy. These people think (a) there is a consensus among scientists, (b) climate models work and (c) carbon dioxide at 336 parts per million is somehow tipping the balance of the planet's greenhouse mechanism while water vapor does not. Oh, and (d) melting ice will raise water levels.

  • Andrew Krause

    Nevermind that I fat fingered the figure - were still talking about a fantastically small number that at either figure is still less than a half of a percent of overall composition. Increasing next to nothing by 68% still leaves you at next to nothing. Carbon dioxides potency as a greenhouse gas are popularly exaggerated (as are the I'll effects associated with warming).

    All the worlds glaciers hold 2% of the planets water. The worlds oceans are shaped like trumpet horns, not cereal bowls. Simple calculus tells us a 2% increase in volume along a inverted paraboloid achieves a negligible rise.

    Sorry if I'm not up to panicking over pseudo science. The whole thong lacks prima fascia believability.

  • Ralph Forrest-Ball

    Carbon dioxide is currently 394 ppm (not 336). CO2 naturally fluctuates between 190 and 280 ppm, with an average of 235, according to ice cores taken all over the planet, going back a couple million years. Only since the industrial revolution has it gone above 300, and now we're almost up to 400. 394 is the current reading, compared to the normal level of 235. That's a difference of 68%. I have no trouble believing that changing something by 68% could have serious consequences

    Oh, and no one is suggesting that floating ice could raise water levels when it melts, but Greenland has huge quantities (over half a million cubic miles) of ice which is sitting on land. If that ice melted, the water wouldn't stay on the land, it would run down into the ocean, raising sea levels by more than 20 feet. Try this experiment at home: put a bagel-sized rock into a cereal bowl and pour some water around it, not quite high enough to cover the rock. Now put an ice cube on top of the rock and wait for it to melt. See the water level rise.