Green Roofs The New York Observer reports 10/13/08

GREEN ROOFS

To the Editor:

Re: "New York Has Ten Olympic Pools' Worth of Green Roofs"
[posted to observer.com on Oct.6]:
Ten Olympic pools comes out to about 123,000 square feet, or a mere 2.62 acres.
Central Park is about 843 acres.
Here at Columbia University, we've estimated that there may be up to 20 times Central Park's area in rooftop space in the New York City area, including all the boroughs.
So we've got a long way to go towards making productive use, via green roofs of this currently wasted-indeed, environmentally harmful-urban land-surface area.
submitted by LETTER TO THE EDITOR
Stuart Gaffin
Adjunct Associate
Research Scientist
Center for Climate Systems Research
Columbia University
Manhattan