A mapping effort called "crowdsourcing" has been developed by a team from Princeton University.  It will be used  to determine whether land on the sub-Saharan Africa terrain is being actively farmed.  The team includes Professor Kelly Caylor, Woodrow Wilson researcher Lyndon Estes, OIT analyst Dennis McRitchie, Wilson School lecturer William Guthe, and 2 undergraduates Jonathan Choi '15 and Reka Zempleni '16.

The Daily Princetonian has a detailed story on this work: http://www.dailyprincetonian.com/2012/12/06/32100