There’s no body of water on the planet that’s getting more attention—and causing more worry—than the Gulf of Mexico, and rightly so. Until BP’s gushing oil well is capped, that will be central fight in the environment wars. The good news is that even pessimists believe that the relief wells now being drilled will do the job and seal the spill before the end of summer. The bad news is that we can then turn our worries back to the Earth’s other ailing oceans, seas and gulfs. And it’s the Weddell Sea, the Scotia Sea and the other regions around the West Antarctic Peninsula that today are raising concern.
Sea levels are rising everywhere around the world, but the West Antarctic Peninsula is contributing more than its share—about 10% of the global increase. That’s in part because, like the Greenland ice sheet, the Antarctic sheet is anchored to land. Every drop that melts away is one drop added to the ocean. The Arctic ice cap, by contrast, could melt away entirely and wouldn’t add so much as a millimeter to sea levels, since it floats on the Arctic Ocean and already displaces as much water as it ever will.
If the Antarctic is one of the biggest reasons for the creep of the seas, the Pine Island Glacier (a formation with the unfortunate acronym PIG) is mostly to blame. A new study in Nature Geoscience reports that the 155 mil. long, 1.2 mi. deep ice formation is slipping its anchorage atop a 100 ft. peak on the ocean floor as a result of rising water temperatures and steady melting. The thinner the glacier gets, the more it drifts into the sea, and the more comparatively warm, circulating water can flow beneath it. That just speeds the process further. Wrote Stan Jacobs, one of the co-authors of the new study:
“Since our first measurements in the Amundsen Sea, estimates of Antarctica’s recent contributions to sea level rise have changed from near-zero to significant and increasing. Now finding that the PIG’s grounding line has recently retreated more than 30 km from a shallow ridge into deeper water, where it is pursued by a warming ocean, only adds to our concern that this region is indeed the ‘weak underbelly’ of the West Antarctic Ice Sheet.”
The crisis in the Gulf of Mexico is often called a slow motion disaster, and in many ways it is. The melting of the glaciers, however, is slower still—and there’s no such thing as a relief well to stop it.