World's water cycle: schematic and residence time
The water cycle consists of precipitation, evaporation, evapotranspiration and runoff. This graphic explains the global water cycle, showing how nearly 577 000 km3 of water circulates through the cycle each year. A table of estimated residence times of the world's water shows the estimated times that water resources exist as biospheric water; atmospheric water; river channels; swamps; lakes and reservoirs; soil moisture; ice caps and glaciers; oc...
17 May 2005 - by Philippe Rekacewicz, UNEP/GRID-Arendal
Possible individual ranges of yield and cropland area losses by 2050
Figure 24: Possible individual ranges of yield and cropland area losses by 2050 with climate change (A2 scenario),
non-food crops incl. biofuels (six OECD scenarios), land degradation (on yield and area, respectively, see text), water
scarcity (including gradual melt of Himalayas glaciers, see box and text) and pests (invasive species of weeds,
pathogens and invertebrates such as insects, see text). Although these effects may be considerable, ...
02 Feb 2009 - by Hugo Ahlenius, UNEP/GRID-Arendal