Water stress and its causes

There are 2 replies in this Thread which has previously been viewed 378 times. The latest Post (August 19, 2023 at 6:11 PM) was by SpaceNut.

    New data from the World Resources Institute says that in the next 30 years, increasing temperatures and population will seriously diminish the world’s water supply. Right now 3.3 billion people (40% of the world’s population) live in arid areas and areas with high water stress (see maps); within 30 years there will probably be 4.3 billion.

    This article explores the phenomenon of water stress and shows the most water stressed parts of the world.

    25 Countries, Housing One-quarter of the Population, Face Extremely High Water Stress
    New data on WRI's Aqueduct platform ranks the world's most water-stressed countries. One-quarter of the global population regularly use up their entire water…
    www.wri.org

    Very interesting. They only briefly mentioned increased variability of water supply as a result of climate change but it's worth noting that worldwide, there is less water reaching the ground from the skies. It may not feel like it - what with torrential downpours and flooding all over those bits of the world that aren't burning but although it's coming down harder and heavier, less is actually coming down.

    This is because the warmer the air becomes the more water vapour it can hold before it becomes saturated. There's a general rule of thumb that the moisture holding capacity of air approximately doubles for every 20deg F (11.1 deg C) of temperature increase. A global temperature increase of, say, 0.1 deg in any chosen unit doesn't sound like very much but when you increase the moisture absorbing capacity of the air by even an infinitesimal amount, you have to multiply that by the vast amount of air surrounding the planet which can suck it up and that translates into an awful lot of water that just isn't reaching the earth's surface anywhere any more.