Sea levels could rise by 3 feet in 100 years – NASA

27 Aug 2015

Man-made effects on the Earth’s environment are speeding up the rising sea levels, with NASA predicting the the process will speed up significantly over the next two centuries as ice caps vanish and water expands.

Following the collation of significant satellite-based research, NASA has discussed the varying speeds at which sea levels are rising and, somewhat surprisingly, falling in places.

The Gulf Stream, for example, appears to have shifted a corridor east in the last few decades, leaving a, well, gulf of cooler, lower water to its west.

The Pacific Ocean, too, is largely depleted towards the US and South America due to something called the Pacific Decadal Oscillation, whereas towards Asia it is rising at its fastest rate.

Rising sea levels - ice cap melts

By using extensive satellite research, NASA was able to create graphics highlighting the parts of the world seeing the fastest rises, with predictions that areas in decline will soon start expanding, too.

“Sea level along the west coast of the United States has actually fallen over the past 20 years because long-term natural cycles there are hiding the impact of global warming,” said Josh Willis, an oceanographer at NASA’s Jet Propulsion Laboratory in Pasadena, California.

“However, there are signs this pattern is changing. We can expect accelerated rates of sea level rise along this coast over the next decade as the region recovers from its temporary sea level ‘deficit’.”

The following image shows researchers deploying an autonomous drifter in a meltwater river on the surface of the Greenland ice sheet a few weeks ago.

It was quickly swept away by the fast-moving glacial waters and ultimately swallowed by a moulin, a sinkhole in the ice.


Rising sea levels Image via NASA/Jefferson Beck

Although the scientists will never be able to recover the device from the depths of the ice sheet, they do have the measurements it took and transmitted on its way down the waters.

This will help scientists better understand how the network of streams and rivers that forms on the surface of the ice sheet when ice melts in the spring and summer contributes to sea level rise.

Rising sea levels

Interestingly, the rate at which the ice caps are melting is markedly different from north to south. While the Greenland ice sheet is vanishing in front of our eyes, losing 303 gigatons of ice a decade, the Antarctic ice sheet is losing about a third of that.

This too, though, is soon to change for the worse.

“The prevailing view among specialists has been that east Antarctica is stable, but we don’t really know,” said glaciologist Eric Rignot of the University of California Irvine and JPL.

“Some of the signs we see in the satellite data right now are red flags that these glaciers might not be as stable as we once thought.

“There’s always a lot of attention on the changes we see now, but as scientists our priority needs to be on what the changes could be tomorrow.”

Main image via Shutterstock, body images via Steve Nerem/University of Colorado/NASA/Jefferson Beck

Gordon Hunt was a journalist with Silicon Republic