From today's NYTs: 
<http://www.nytimes.com/interactive/2016/12/09/science/mapping-three-decades-of-global-water-change.html?rref=collection%2Fsectioncollection%2Fscience>

The concluding paragraph:

" The project’s scope, as described in a paper published online 
<http://nature.com/articles/doi:10.1038/nature20584> Wednesday in the 
journal Nature, included the entire archive of three Landsat satellites 
from 1984 to 2015 — about three million high-resolution images, or 
nearly two quadrillion bytes (1.8 petabytes) of data. The images were 
processed in the cloud by 10,000 computers using Google’s Earth Engine 
platform, classifying each 100-foot by 100-foot pixel as water or land."

           Joel Kovarsky