Imagine a sand box.
Make it a good sized one. About three meters on each side, with walls about 30 cms (one foot) deep. Fill the box with clean, dry sand.
Now, gather a dozen soup bowls, fill them with small pebbles or gravel, and sink them upright into the sand so that the lip of each bowl is about a centimeter below the surface. Get a large watering can and carefully fill each of the bowls with water. Lastly, cover each one with sand to hide it below the surface.
Begin calling the bowls 'aquifers' because you are about to earn a quick PhD in fresh water management policy.
Here's the deal.
Your kids want to germinate some seeds in the areas of the sand box where there are no bowls. You tell them they are allowed to push a single straw through the sand into each bowl and suck out as much water as they want to use on their seeds, but you will only allow one cup of relacement water from the kitchen tap to be added to each bowl, per week, and they must start calling that new water 'precipitation'.
Your final exam consists of a single question.
How much water can the kids suck out of each bowl per week during July and August if the plants are to keep growing in the blazing sun until Labour Day?
Pretty obvious, eh?
No more than a cup, the replacement quota, and likely less because each bowl will lose some water soaking to the surface sand above it. That is probably where we should have put the seeds in the first place.
The lesson to be learned is that you can never remove more water from any one bowl than can be replenished from the weekly re-supply. Break this rule and the entire sand box will run dry in a matter of days.
That is what has been done to the Kalahari desert and to much of the South Western USA.
Now Cuba has decided to ask foreign developers to build golf courses?
Raul, good grief!
Fifty years of heroic sacrifice and defiance by a long suffering people now betrayed on the eve of global ecological catastrophe ... and deprived of vindication.