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LIDAR Map Shows Height of Earth's Forests

Posted by Unknown on from the for-tax-purposes dept.

Hkibtimes writes about a recently released map of the Earth's forests. From the article: "A group of scientists from NASA and the University of Maryland have created a unique map that shows the heights of the Earth's forests. The map ... has been created using 2.5 million carefully screened and globally distributed laser pulse measurements sent from space."

3 of 47 comments (clear)

  1. First post by Anonymous Coward · · Score: 5, Funny

    http://xkcd.com/1019/

  2. Google Earth by Cinnaman · · Score: 5, Interesting

    When can we get height data with good enough resolution to show individual trees and buildings?

    1. Re:Google Earth by Anonymous Coward · · Score: 5, Informative

      You need 1m posting or better lidar data to get the individual trees and buildings. For the State of North Carolina, which was one of the first states with complete lidar coverage ( for floodplain mapping purposes), 1/3 of the state was flown at -12m posting distance and 2/3 was flown at 5m posting distance , Even at this relatively coarse resolution, there are about 26 billion x,y,z points for the State data set. You can process this as a single file using GRASS GIS or LAStools in a couple of days on a 2Ghz cpu ( single threaded). Consider that 1 m posting gives you 25 times the data points as 5 m posting and pretty soon you are talking about interesting data set sizes.