NASA: Rising Seas About to Catch Up With the West Coast

Rising Seas are about to become a bigger issue for the West Coast, according to scientists.

Using satellite and other data, NASA scientists have been tracking rising sea levels around the world. They say that natural cycles in the Pacific have been masking effects of sea rise for about the last 20 years. But that’s changing.

“In the next five or ten years, I think the west coast of the United States is going to catch up,” says Josh Willis, a climate scientist at NASA’s Jet Propulsion Lab in Pasadena. He says a major ocean phase known as the Pacific Decadal Oscillation is in the midst of a big shift.

For about the past two decades, the PDO, which Willis describes as “El Niño’s bigger, slower, brother,” was “piling up” warmer water on the far side of the ocean, exacerbating sea rise there. When water warms, it expands.

“So we’ve actually seen a slight drop in sea levels off of our coastline  because of the rearrangement of heat within the oceans,” Willis explains.

That rearrangement could mean an acceleration in the rate that seas rise long the West Coast, eventually overtaking the pace of sea level rise on the East Coast and elsewhere.

“We could be looking at rates in the eastern Pacific two or three times as high as the global rates in the coming years,” says Willis. “So we could be in for wild ride over the next 20 years or so.”

As KQED and San Francisco Public Press have reported recently, billions in shoreline development in the Bay Area are in the planning stages or already begun, despite scientists’ warnings about rising seas.

Scientists say the brewing El Niño will also pile up warm water along California, making coastal flooding that much more likely, very soon. The warm water along the Equator that largely defines El Niño is expected to rival or surpass the legendary “Godzilla” El Niño of 1997-98 in strength.

NASA says global sea levels have risen about eight inches since the beginning of the 20^th century and more than two inches in the last 20 years. Though simple thermal expansion of the water accounts for about a third of the rise so far, climate scientists expect melting glaciers and ice sheets to play a much larger role in coming years.