Thursday, September 11, 2008

Hurricanes


In 1989 Bill McKibben wrote about the predicted rise of super-hurricanes in his respected book "The End of Nature." He says the intensity of a hurricane is determined by how low the air pressure gets. The lower the air pressure, the more intense the hurricane. Simple enough. Under 1988 water temperatures, scientists calculated that no hurricane in the Atlantic could possibly drop below 885 millibars in air pressure (which equates to 200 mile per hour winds). But if the temperature of the water were to rise only a couple of degrees in the tropics, the air pressure for storms would be able to drop much lower. The result: stronger, super Category 5 hurricanes. Well, in 2005, Hurricane Wilma shattered the 885 millibar barrier (with a reading of 882--and a few millibars make a HUGE difference, apparently). It struck shortly after Katrina, and was the fourth category 5 hurricane that season. Oh, did I mention that water temperatures in the tropics are, in fact, warmer now than in 1988?

Yet despite these scientific predictions from two decades ago, people today still refuse to add 2+2 when determining whether global warming has any link to stronger hurricanes. Fortunately, Ike is only supposed to be a category 3 when it hits land again.