Xueliang Cai and Landsat Science Team member, Prasad Thenkabail, have used satellite data, including Landsat, to calculate crop water productivity, i.e. how much water is used for crop production—the so called “crop per drop.” Details of their research are available on the SPIE website [external link].
Reference:
Cai, X. and P. Thenkabail (2010). Using remote sensing to assess crop water productivity. SPIE Newsroom, doi: 10.1117/2.1201002.002576
+ Using remote sensing to assess crop water productivity [external link]