FYI, yesterday’s Nature has a cover story on the Global threats to human water security and river biodiversity by C. J. Vörösmarty (CCNY) et al (doi:10.1038/nature09440). Following that, this story has been posted practically everywhere on the media by now, including BBC.
On their project website (http://www.riverthreat.net), you can find/download their published data and maps (0.5-deg, global) of four water “threats” as well as 23 (!) drivers in PNG, ESRI ASCII, NetCDF, and KML.
· Main article: http://www.nature.com/nature/journal/v467/n7315/full/nature09440.html (login required)
· Methodology: http://www.nature.com/nature/journal/v467/n7315/extref/nature09440-s1.pdf (freely accessible)
· Data and maps: http://www.riverthreat.net/data.html