You just can’t beat the timing of two breathlessly announced reports suggesting that global warming is causing irreversible melting of Antarctic glaciers which will cause a catastrophic sea level rise.
Their nonaccidental tandem release follows hyperventilating primal scream conclusions chronicled in the Obama Administration’s new National Climate Assessment that “climate change, once considered an issue for a distant future, has moved firmly into the present.”
Yup. Another meltdown issue is now absolutely clear. Climate changes!
One of those studies conducted by a group at NASA’s Jet Propulsion Laboratory and the University of California-Irvine used satellite measurements to track “six rapidly melting glaciers” between 1992 and 2011.
The other, conducted at the University of Washington, developed computer models to predict that coastal melting could cause the collapse of the West Antarctic ice sheet within 200 to 900 years. This, they claim, might cause global sea levels to rise by as much as 10 feet.
As for influences surrounding this knuckle-biting alarm, the researchers place blame on broad patterns of climate change. Included are rising regional temperatures, warming ocean currents, and changing wind patterns. And while both research teams agreed that the existence of warm water might actually be part of the natural ocean system, they assert that climate change is a contributing factor in bringing the warm water in contact with the ice and causing it to melt.
But wait a minute. This isn’t exactly a new development that is readily attributable to smokestacks and SUVs. The West Antarctic ice sheet has been melting at about its recent rate over thousands of years. This condition is expected to continue until either it entirely disappears, or until such time as the next Ice Age intervenes to stop it.
For some additional perspective, consider that the West Antarctic ice sheet, which has been experiencing modest warming contains less than 10% of the continent’s total ice mass. That other 90% has been getting colder, with no decline in polar ice extent since satellite recordings first began in 1979. As a matter of fact, Antarctic polar ice extent just surpassed the greatest month-of-April measurements in satellite-recorded history.
The JPL/UC-Irvine satellite study observed that a West Antarctic Pine Island glacier of particularly high concern has retreated 19 miles since 2005. This fast-moving ice discharger first gained lots of attention when satellite measurements revealed a retreat rate of about 1.2 kilometers per year between 1992 and 1996. A large iceberg that broke loose from the glacier caused media-trumpeted speculation that this “race to the sea” heralded the beginning of the end for the West Antarctic ice sheet.
A different Pine Island glacier satellite study reported in a 2000 issue of the Journal of Geophysical Research determined that ice over the entire drainage basin thinned by about 1.6 meters per year between 1992 and 1999. Such dynamics are typically driven by phenomena operating on time scales of hundreds to thousands of years, not by 20th-century warming. [Editor’s note: Thus there is no need to jump off a cliff!]
And what net contribution to sea level rise will result if this thinning rate continues unabated? It will amount to about 6 mm — the width of a paper clip each century.
Scientists involved with the most recently reported studies admit that the West Antarctic ice sheet is not melting due to warming air temperatures, but rather because naturally occurring warm ocean water is being pulled to the surface by the intensification of winds that encircle the continent. They then hypothesize that those stronger winds are being influenced by human-caused global warming.
There’s at least one big potential problem with that theory. Although atmospheric CO2 levels have risen, global temperatures have been flat for going on the past 17 years.
Here’s something else those study reports did not bother to mention. In 2012 some experts from the University of Aberdeen and British Antarctic Survey discovered a huge, 1-mile-deep rift valley about the size of the Grand Canyon located beneath the ice in West Antarctica. Since this previously hidden ice-filled basin connects directly with the warmer ocean, they think it might constitute a major cause for much of the melting in this region.
It might also be worth mentioning that a chain of active volcanoes has recently been discovered under that West Antarctic ice sheet as well. While it is believed that eruptions are unlikely to penetrate the 1.2- to 2-km-thick overlying ice, researchers conclude that they could generate enough melt water to significantly influence ice stream flow.
So what does all of this really mean? The White House will continue to tell us that it means more fossil fuel regulations and wind power subsidies are urgently needed to prevent catastrophic coastal flooding. Those who spread such nonsense are already in way over their heads.