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For Much of the World, Demand For Water Outstrips Supply
ananyo writes "Almost one-quarter of the world's population lives in regions where groundwater is being used up faster than it can be replenished, concludes a comprehensive global analysis of groundwater depletion (abstract). Across the world, human civilizations depend largely on tapping vast reservoirs of water that have been stored for up to thousands of years in sand, clay and rock deep underground. These massive aquifers — which in some cases stretch across multiple states and country borders — provide water for drinking and crop irrigation, as well as to support ecosystems such as forests and fisheries. Yet in most of the world's major agricultural regions, including the Central Valley in California, the Nile delta region of Egypt, and the Upper Ganges in India and Pakistan, demand exceeds these reservoirs' capacity for renewal."
Physics 101.
When you pump water out of the ground, it leaves a void. When you don't backfill, the void eventually collapses. The oil industry is aware of this problem (that and oil doesn't tend to want to just lift itself out of the ground once the initial pressure does its thing), which is why they use seawater to displace the oil: seawater is pumped in, oil flows out or is pumped out leaving the void which is then backfilled under gravity through a strategically placed hole or two.
Back to the topic: the stable system of rain=>aquifer is disrupted to greater or lesser degrees by human activity. That's obvious. The amount of rain remains constant (more or less), which means the amount of water removed from the aquifer is gone. Simple as. The global water industry has a few options to try and deal with this problem before we start seeing entire cities disappearing into sinkholes:
1. Backfilling. Something not currently done, but it begs the question as to what to backfill with?
2. Alternative sources. We have viable desalination technology (geothermal, solar stills, seat salt extraction plants(!))... we have made great strides in atmospheric water extraction to the point where a plant in the middle of a desert can turn sand into golf course. One option that I don't think has been properly explored is a wide area water grid, possibly national or international in scale. We have the technology, we have the capability, the chock under that wheel is politics.
Operation Guillotine is in effect.
Man, I'm willing to pay an extra 14 cents on a Papa John's pizza if it means the poor bastards preparing and delivering it have health insurance now. Hell, I thought it would be an extra dollar.
It's good to see your priorities are in order, though. Fuck everyone else's needs if they make the price of a pizza go up by less than fifteen cents.
1. Backfilling. Something not currently done, but it begs the question as to what to backfill with?
Oil, obviously.
The issue, of course, is not "water"; it's freshwater. We have a lot of water on this planet. Generally it can exist in 5 states: seawater, clouds, freshwater (or what I like to call "drinkable land water"), aquifer water (underground water), and snow/ice.
Around the world aquifers are being depleted. This is a problem because this is one of the most low-energy (and technologically well understood) ways to harvest drinkable land water. And humans are not the only living creatures that use aquifer water! If there is not aquifer water for plants then the plants are completely dependent on rainwater or flowing drinkable land water (rivers, creeks, etc., which are all on their way to becoming seawater again ASAP). This is a precarious state to be in, because on a macro scale, once plants start to be incapable of doing their job (providing ground shade, ecosystems for biomass, improving and retaining soil structure, etc.) a landscape can be on the road to desertification. What does this mean? That means that it's going to stop raining. This has happened, many times, because of human modification of the landscape and has led to the total collapse of multiple powerful civilizations (Jared Diamond's book "Collapse" talks about things like this).
So what are we supposed to do? Say you are an ecological steward (or policy maker) for a couple hundred acres of land that are on their way to desertification or that are already in a stable, but arid, water cycle. It is easy to think of water in terms of accounting and cash-flow, what is the big picture that will make the landscape profitable and growing in "financial" reserves?
The big picture is very simple: we are trying to make seawater into permanent land water. The more net land water the Earth has, the more stable and abundant the existence of terrestrial life on this planet, in general, will be.
(Just remember we're practicing for Mars!)
How do you do this? The input of "free" water we have (meaning no energy cost for the conversion from seawater to potential land water) is rain. We need to make sure that as much rain as possible stays as underground water... or the *sixth* form of water that I haven't mentioned yet: biomass! There is a lot of water in biomass. And it is a relatively closed loop (meaning that once some water becomes biomass it will stay in the biomass cycle for a long time). Insects, plants and *especially* soil biology are some of the greatest resources we have for storing water on land instead of losing it to the ocean.
And then of course, we are all technologists, so I think it is also worthwhile suggesting that we should be using renewable energy resources to desalinate saltwater and just pump it back (I don't know if these techniques have even been invented yet) into our aquifers and ecologies.
there is no water shortage, there's only energy shortage. There's water everywhere for the taking. With cheap enough energy, you can get all the freshwater you need from distilling seawater or towing icebergs from the Arctic or reverse osmosis or any of a thousand different ways.
You seem to equate the matter with death.
No shit. And you seem to think "exists" means "will always exist, even if we don't do anything to preserve it."