Tuesday, September 25, 2007

History Channel: Glacier Meltdown (Mega-Disasters series)

Mega Disasters: Glacier Meltdown. The History Channel, on Tuesday September 25, 2007, broadcast this program that starts by documenting the loss of glacial ice in Greenland, the Andes, the Alps, the Himalaya, even Kilimanjaro at 19000 feet on the Equator. The loss of ice means the loss of reflection, and a “feedback” effect that accelerates warming. The same effect explains the prolonging of cold weather in the late winter or early spring. But with the loss of snowpack, springs will come even earlier with rising sun angle.

The film documents the catastrophic effect of the rise of sea level, but other global warming films have done this. But the film maintains that major cities along the East Coast are at far more risk that people have supposed. A Category 2 hurricane, positioned to hit in the hook underneath New York, could floor lower Manhattan and the financial district.

The program places particular emphasis on the vulnerability of some of Washington DC. The Mall is only six feet above sea level. Sea level could rise three feet by 2050. Imagine a Category 5 hurricane forming off the North Carolina Coast, moving into the Chesapeake Bay, causing a fifteen foot storm surge overrunning Annapolis (the Naval Academy), and then funneling fifteen feet of water up the Potomac overrunning lower parts of Washington DC. The flood water would almost reach the White House. It would flood Reagan National Airport. True, parts of Washington and nearby Arlington are almost 500 feet, and they would be OK.

The TV guide claimed that the program would document a new dust bowl that can occur with global warming (dwarfing that of John Steinbeck’s 1930s) but apparently that will be another program.

The island nation of Tuvala, less than 6 feet above sea level, between Hawaii and Australia, was presented. The nation may sink, and the country is considering suing the US.

Picture: The National Park Service documents the flood in Harpers Ferry in 1996, from torrential rains. Towns above the Potomac Fall Line would not be at risk from a hurricane flood, but Appalachian towns are at risk from torrential rains that follow hurricanes and flood streams. Further west, strip mining increases the flood runoff risk to towns below.

No comments: