Wednesday, December 12, 2012

Sea Levels Rising Faster Than Predicted - and Accelerating

The Guardian reported on November 27th that US coastal cities are in danger as sea levels rise faster than expected.  

In fact, the paper notes, sea levels are rising much faster than initially predicted, endangering "low-lying population centers" (that's dry, enervated language for places that a LOT of people live, like New York City, Los Angeles, and Jacksonville, Florida) and requiring even more ambitious efforts (dry, enervated language for huge legislative measures and associated public works projects) from authorities to protect them.

From the NY Emergency Manager's Page, NOAA

The Guardian piece quotes a more extensive report by Climate Central.  Entitled "Surging Seas," the report is grimmer than grim.  Here's just a sample:

"Global warming has raised sea level about eight inches since 1880, and the rate of rise is accelerating. Scientists expect 20 to 80 more inches this century, a lot depending upon how much more heat-trapping pollution humanity puts into the sky. This study makes mid-range projections of 1 to 8 inches by 2030, and 4 to 19 inches by 2050, depending upon location across the contiguous 48 states."

"Warming and sea level rise are both accelerating, as is the rate of decay of ice sheets on Greenland and Antarctica.  Loss of ice from these sources has the potential to raise sea level by many tens of feet over centuries. In the warm period before the last Ice Age – when the planet was as warm as we expect it to become by 2100 or sooner, at least without deep and immediate cuts to pollution – global sea level very likely reached over 20 feet higher than it is today, an eventual sea level we could be committing to within decades if not already.  That rise would be enough to drown many major coastal metropolises."

"The population and homes exposed are just part of the story. Flooding to four feet would reach higher than a huge amount of dry land, covering some 3 million acres of roads, bridges, commercial buildings, military bases, agricultural lands, toxic waste dumps, schools, hospitals, and more. Coastal flooding made worse by global warming and rising seas promises to cause many billions of dollars of damage over the coming decades."