LIDAR

http://www.loc.gov/exhibits/911/911-maps.html

This map shows the elevations of the World Trade Center and surrounding area in July of 2001. Of my research on maps, this was, by far, the most interesting. This map was grouped with other LIDAR maps of the area as well that I am going to include.



The map above was taken on September 15th 2001.




The above map was done on September 17th 2001.

The website I took these maps from said they used LIDAR to "provided elevation data of the Ground Zero site. It enabled emergency managers to assess damage through the smoke. The LIDAR data was used to determine changes in the rubble pile and to create 3-D digital elevation models that demonstrated the extent of the destruction."

(I found this very interesting. The quote comes directly from the website previously cited under the first image.)