Reference:
DeFries, R.S., T. Rudel, M. Uriarte, and M. Hansen (2010). Deforestation driven by urban population growth and agricultural trade in the twenty-first century.Nature Geoscience, doi:10.1038/ngeo756.
+ Article abstract [external link]
+ City Dwellers Drive Deforestation in 21st Century, Scientific American [external link]
Scenes from the Polar Night
Landsat satellites have begun regularly acquiring images of ice at the poles during the winter, with enlightening results.