There is more water in the ground than in all the world’s rivers and lakes
combined. To use this valuable resource to good effect, we need to understand
its place in the water cycle
WATER is one of the most commonplace compounds on Earth. Yet, thousands of
people die every day because they do not have enough, or because their supply
is contaminated. How can this happen on a planet that has an estimated 1400
million cubic kilometres of water? That is 250 000 million litres for every
man, woman and child (1 cubic kilometre is 1012 litres).…
