While researching yesterday's post on global warming and the metropolitan area, I came across a map of projected inundation levels should New York be struck by a category 3 hurricane.

Mind you, category 3 is not Katrina-strength; Katrina was a category 5. Category 3 is defined as follows:

Winds 111-130 mph (96-113 kt or 178-209 km/hr). Storm surge generally 9-12 ft above normal. Some structural damage to small residences and utility buildings with a minor amount of curtainwall failures. Damage to shrubbery and trees with foliage blown off trees and large trees blown down. Mobile homes and poorly constructed signs are destroyed. Low-lying escape routes are cut by rising water 3-5 hours before arrival of the center of the hurricane. Flooding near the coast destroys smaller structures with larger structures damaged by battering from floating debris. Terrain continuously lower than 5 ft above mean sea level may be flooded inland 8 miles (13 km) or more. Evacuation of low-lying residences with several blocks of the shoreline may be required. Hurricanes Jeanne and Ivan of 2004 were Category Three hurricanes when they made landfall in Florida and in Alabama, respectively.

Here is that map, showing a projection of how far inland water could reach in the event of such a hurricane directly hitting the City. Six category 3 hurricanes hit the Northeast in the twentieth century, the most recent, hurricane Gloria, in 1985.

Today's New York Times reports that homeowners in the metropolitan area are already losing their insurance coverage due to heightened insurance company concerns following Katrina.

The [cancellation] letter said that “hurricane events over the past two years” had forced the company to limit its exposure to further losses; and that because the Grays’ home on Long Island was near the Atlantic Ocean — it is 12 miles from the coast and has been touched by rampaging waters only once, when the upstairs bathtub overflowed — their 30-year-old policy was “nonrenewed,” or canceled.

The existing climate models uniformly predict an escalation in hurricane activity due to global warming. But even if there were no such thing, a brief glance at the map above - half of Brooklyn and Queens, a quarter of Staten Island, the financial district and half the west side of Manhattan under water - indicates that there is a need for an anticipatory policy response.

Katrinas do happen. Are we ready for this?