Technically this shows "above-ground woody biomass," but in practical terms it is a map of tree density.
Over six years, researchers assembled the national forest map from space-based radar, satellite sensors, computer models, and a massive amount of ground-based data. It is possibly the highest resolution and most detailed view of forest structure and carbon storage ever assembled for any country.Posted at Neatorama by Miss Cellania, who found it at NASA's Earth Observatory (their Image of the Day page is well worth a bookmark).
Forests in the U.S. were mapped down to a scale of 30 meters, or roughly 10 computer display pixels for every hectare of land (4 pixels per acre). They divided the country into 66 mapping zones and ended up mapping 265 million segments of the American land surface...
p.s. - The embedded image enlarges with a click, but for maximum detail enlarge x2 the original at the NASA link.
(Reposted from 2012 for Arbor Day 2015)
the midwest looks pretty bleak. I blame the farmers.
ReplyDeleteMuch of the midwest was actually prairie in the past. The farmers and pioneers actually brought trees into the area.
ReplyDeletei'd be interested to know what types of trees are prevalent in certain areas, also. Indiana will be short most if not all of its ash trees in the next 5 years or less...that's a lot of trees.
ReplyDeleteThanks for mentioning that Fuzzarelly. I live in Nebraska, the birthplace of National Arbor Day, originated in Nebraska City.
ReplyDeleteNebraska National Forest is in fact the largest forest in the USA planted by hand.
I used to have a link to tree distribution (change over time) and the mid-west actually has greatly increased its trees over the last century. I thank the farmers for leading the charge.
here, read this article. deforestation and erosion in iowa are a problem.
ReplyDeletehttp://www.nytimes.com/2011/04/13/business/13erosion.html
"When prices for corn and soybeans surged last fall, Bill Hammitt, a farmer in the fertile hill country of western Iowa, began to see the bulldozers come out, clearing steep hillsides of trees and pastureland to make way for more acres of the state’s staple crops. "
I don't know much about the US, and I was wondering what's in the grey area in the middle. It appears to be farmland from Minnesota to Louisiana (http://en.wikipedia.org/wiki/File:Prime_farmland_USA_1997.png), but what's west of that (Montana - New Mexico)?
ReplyDeletepom, here's a topographic map of the U.S. to show you the location of the mountains in the west -
ReplyDeletehttp://www.united-states-map.com/us402112.htm
For the most part, the mountains are not too high to support trees, but what they do do is to alter the rainfall patterns by creating a "rain shadow" -
http://en.wikipedia.org/wiki/Rain_shadow
You can see similar effects in most countries where the prevailing winds come off the ocean (in the case of the U.S., the prevailing wind direction tends to be west-to-east).
That is way less forest than I expected.
ReplyDelete