Reuters recently warned us of rising seas based on accelerated melting of the West Antarctic ice sheet. If true, Atlantic and Gulf of Mexico waters could flood Florida’s beaches in as little as a few decades.
On the heels of the National Climate Assessment (NCA), White House adviser John Podesta is corralling public support for EPA’s CO2 regulations that will increase everybody’s electric rates without significantly reducing future temperatures. A pillar in his argument is CO2’s alleged role in warming the oceans and melting polar icecaps, causing the seas to rise.
But what about the ice sheet? It is firmly attached to a bowl-like platform of bedrock that would be submerged under water but for the presence of the ice. The weight of more than mile-thick ice impedes the “collapse” (calving icebergs) at the edges. A succession of submarine ridges in the path of potential melting blocks entry of seawater beneath the “grounded” ice.
Imminent melting of the West Antarctic ice sheet is thus open to question. Clearly, this entity existed between and during earlier glacial periods, the latest ending some 10,000 years ago. A small ice shelf along the side of the northward extending Antarctic Peninsula melted 6,000 years ago, then reconstituted.
Pessimism over a disappearing ice sheet may, like rumors of Mark Twain’s premature demise, prove exaggerated. It’s worth noting that subsequent cool-downs followed each warming pulse during the modern post-glacial period. The British Antarctic Survey reports occasions of partial melting, then re-establishment of Antarctica’s ice shelves several times from 8,000 years B.C. forward.
The catastrophic melting of the polar icecap required to dramatically raise sea level — first predicted in 1922 and flagged in the NCA document — shows no signs of materializing. News accounts of a European Space Agency study, by misinterpreting the data, proclaim a melt rate of the West Antarctic ice sheet twice what previously had been thought, re-igniting warnings of imminent collapse. Closer examination shows the new data consistent with the former; thus there is no abrupt increase.
Antarctica’s glaciers have dwindled very slowly since the end of the last ice age. At current rate, thousands of years would be required to raise ocean levels by the 12 to 13 feet mentioned in various news accounts, while intervening cold periods could reverse the process, as has happened repeatedly in the geologic past.
Statements that suggest anthropogenic CO2 is the primary agent responsible for triggering high-velocity circumpolar winds in the Southern Ocean (that drive “warm” ocean currents against the ice shelf) are speculative for a region long notorious for high winds and treacherous seas.
Running counter to a melting ice sheet are recent satellite observations suggesting the ice mass over much of the interior of the Antarctic continent is increasing, along with indisputably expanding sea ice around the perimeter. These observations are consistent with a somewhat warmer (comparatively speaking) Southern Ocean generating greater amounts of snowfall over the continent, helping to replenish glacial ice.
Efforts by NASA and others to model regional and global climates have disappointed adherents. Climate models, in aggregate costing more than $1 billion, all failed to anticipate the ongoing 18-year pause in global warming since 1996-97. Models also fail to replicate known temperature records beginning in 1950.
In the language of climate scientists’, the models being misapplied to formulate energy policy lack “skill.”
These failures spring from a lack of adequate understanding of the physical processes taking place on and above the Earth’s surface. It is the processes, and not the models, which determine our weather in the near term and changing climates over decades and longer.
Making decisions based on ineffective models should be viewed as suspect for the purposes of setting federal policies that will assure higher utility costs for Florida residents and elevated risk of brownouts, without reducing beach erosion.
Featured Image Courtesy of Michelle Meiklejohn/freedigitalphotos.net
