Similar to how warming temperatures are more prominent and noticeable in certain parts of the globe, sea levels rise at varying rates from one coast to the next as well.
According to a study from the U.S. Geological Survey published in the journal Nature Climate Change, parts of the East Coast of the United States are experiencing sea level rises as much as 3 to 4 times higher than the average around the world.
“That makes storm surges that much higher and the reach of the waves that crash onto the coast that much higher,” said study leader Asbury Sallenger of the US Geological Survey.
“In terms of people and communities preparing for these things, there are extreme regional variations and we need to keep that in mind. We can’t view sea level rise as uniform, like filling up a bath tub. Some places will rise quicker than others and the whole urban corridor of northeast US is one of these places.”
The recent acceleration of sea level rise has not been seen before on other US coasts, and scientists predict it’s due to slower currents in the Atlantic. The currents are driven by cold dense water sinking into the Arctic, but with the oceans warming and less freshwater flowing into the Arctic from Greenland due to melting glaciers, the water is sinking much less quickly. This causes a “slope” and pushes sea levels up on the coast.
The 600-mile region from Cape Hatteras, North Carolina to north of Boston is now considered a hotspot for rising sea levels. Since 1990, this area has experienced 2-3.7 millimeters of sea level rise per year, next to a global average of 0.6-1 millimeter annually. This is pretty bad news for North Carolina, which recently enacted a bill allowing state planning agencies to basically ignore rising sea levels.
By the end of the century, these studies predict greenhouse gases could cause sea levels on the east coast to rise as much as 80 centimeters. If emissions continue at their current pace, we could see rises as much as a meter and a half.
As long as temperatures continue to rise, so will sea levels. It’s a reality that governments can’t really afford to ignore.