Showing posts with label sea level rise. Show all posts
Showing posts with label sea level rise. Show all posts

Wednesday, September 12, 2007

I'm Melting--The Incredible Shrinking Polar Ice Cap


Like the Wicked Witch, sprayed with water by Dorothy in the Wizard of Oz, our polar ice cap is melting fast (but not into a yucky puddle of green with a hat on top).


The National Snow and Ice Center in Boulder, Colorado, reports that arctic sea ice is at a record low right now, shattering the previous record, set in 2005, with a 20 percent greater reduction. See "Actic Sea Ice Cover At Record Low." (The satellite photo to the right here shows quite a bit of open ocean at the North Pole. If you really zoomed in, you might see Santa sun-bathing.)


Based on this data, scientists are now saying we may have an ice free North Pole (at the end of summer)by as early as 2030.


Wow, that was fast! It was only a week ago that we passed on new research predicting an ice free arctic by 2050, which moved up earlier predictions from the year 2100.


The good news is that melting of the arctic ice cap does not raise sea levels appreciably. Indeed, it could open up the fabled "Northwest Passage" for ship transit from the Atlantic to the Pacific, making a lot of Panamanians very unhappy about the sudden reduced relevance of their canal.


Unfortunately, the bad news is a lot worse. If the Arctic Ocean is melting much, much faster than most computer models projected, then it is likely that other melting--the kind that does raise sea levels--is also accelerating faster than expected. The big ones are the Greenland ice sheet and Antarctica. If the Arctic ice is melting at a record pace, then Greenland is probably not far behind. (It's more difficult to measure Greenland--we'll see those reports later in the year after more data is crunched.) Antarctica doesn't necessarily follow what's going on in the Arctic, but it stands to reason that warming is accelerating at the South Pole too.


We expect that the Intergovernmental Panel on Climate Change (IPCC) to significantly revise--upward--its projections of sea level rise over the next century. A more rapid rise in sea levels has a number of very serious implications. For one, we'd be foolish to invest billions in trying to protect all of existing New Orleans if it's just going to be a losing battle. Instead, we need to give serious consideration to other at risk cities, such as New York, Norfolk, Baltimore, Miami, Tampa and quite a few others.