Tree Canopy Height from 1650 to 1992

Check out my hero, Ben Franklin, opining that land cleared of forest absorbed more heat....

“By clearing America of woods,” Benjamin Franklin wrote, Americans were “Scouring our Planet…and so making this Side of our Globe reflect a brighter Light to the Eyes of the Inhabitants of Mars or Venus” (quoted in Williams, M.). However, it was not the inhabitants of Mars or Venus that were likely to be affected by the newly bright land, the prescient weatherman noted, it was the very Americans who were carving farms out of the forest. Franklin and other colonists agreed in 1763 that “cleared land absorbs heat and melts snow quicker,” but Franklin believed that years of observations would be necessary before anyone could make any conclusion about the effect of deforestation on local climate. He was right. In 2008, 245 years later, scientists are just beginning to understand how much land use can change the weather.

Click on the link to see a cool progressive map:

http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17913