Sea Levels are Already Rising in America’s Southeast. A Preview of the Future? – Slashdot
The Washington Post visits one of over 100 tide-tracking stations around the U.S. — Georgia’s Fort Pulaski tide gauge:
Since 2010, the sea level at the Fort Pulaski gauge has risen by more than 7 inches, one of the fastest rates in the country, according to a Washington Post analysis of National Oceanic and Atmospheric Administration data for 127 tide gauges. Similar spikes are affecting the entire U.S. Southeast — showing a glimpse of our climate future… [I]n the previous 30 years, the ocean rose about 3.7 inches. And the deluge stretches all across the South and the Gulf Coast; over the past 14 years, sea levels in the U.S. South have risen twice as fast as the global average…
Scientists suspect part of that is because of the Gulf Stream — a long band of warm water that follows the coast up from the equator and then, near Cape Hatteras, turns out into the Atlantic Ocean. The waters of the Gulf Stream and the Gulf of Mexico are warming faster than other parts of the Atlantic, boosting sea levels. “The Gulf of Mexico has warmed exceptionally fast over the past decade and a half,” Piecuch said. “It’s uncontroversial.” But scientists have puzzled over where all that heat is coming from… [T]he current heat could be part of long-term variations in ocean currents, and not a clear signal of climate change. But the fact that the change is linked to heat — at the same time as the entire ocean is taking on excess heat from global warming — makes some experts suspicious. “This particular mechanism does not immediately suggest it’s just natural variability,” [said Ben Hamlington, a research scientist who leads NASAâ(TM)s sea level change team].
For now, sea levels in the Southeast are surging — and they provide an early picture of what most of the United States, and the rest of the world, will experience as oceans rise… On Tybee Island — whose population of 4,000 swells to over 100,000 during the summer months — leaders have gotten used to the constant fight against the waves. Five or six times a year, high tides sweep over the one road that connects the island to the mainland, cutting residents off from services. By 2050, scientists estimate, those high tides will happen 70 days a year. With the help of the U.S. Army Corps of Engineers, the city has built dunes to protect vacation homes and local storefronts from the rising water; many homeowners have also raised their properties high up into the air. In Savannah, small businesses and city streets are washed in floods even on bright, sunny days — thanks to high tides that surge into the drainage system. The city estimates that it will cost $400 million to update the stormwater infrastructure over the next two decades. So far, it has raised $150 million…
Other states and cities will soon see the same effects. NASA projections show that in the coming decades, many cities in the Northeast will experience up to 100 more days of high-tide flooding each year.
“Some researchers think that the Southeast acceleration may be linked to long-term weather patterns in the Atlantic Ocean like the North Atlantic Oscillation.
“If so, the trend could switch in the coming decades — with areas of the Northeast seeing rapid sea level rise while the trend in the Southeast slows down.”