The Earth’s Fresh Water Aquifers Are Depleting
Image: Water Resources Research
The total amount of fresh water on earth is a precious commodity. Only 4% of all the Earth’s water is ‘fresh water’, and most of it (~ 70% of the 4%) is unavailable and locked up in ice caps and glaciers. That leaves approximately 30% of the 4%, most of which is deep underground (only 0.0067% is above ground in lakes and rivers!). In the big picture of things, that’s not so much fresh water compared to all water on Earth.
The problem is, new NASA data shows “how the world is running out of water”. More than half of Earth’s 37 largest aquifers are being depleted, according to gravitational data from the GRACE satellite system.
The preparedness-minded know that water is a most precious resource. For some it is plentiful, but for others it is scarce or non-existent. The residents of California are now discovering the value of fresh water as they themselves run out. As their severe drought continues, they will be shocked as to what is about to happen (crashing real estate prices, water ‘wars’, and even exodus).
This underscores the recent NASA report which indicates that the world’s largest underground aquifers – a source of fresh water for hundreds of millions of people — are being depleted at alarming rates – including California which is currently tapping aquifers for 60 percent of its water use as its rivers and above-ground reservoirs dry up. Some expect water from aquifers will account for virtually every drop of the state’s fresh water supply by year end.
Aquifers can take thousands of years to fill up and only slowly recharge with water from snow-melt and rains. Now, as great demand has been placed on water from aquifers across the globe, the water reservoirs are being stressed.
California’s Central Valley Aquifer was the most troubled in the United States. Also running a negative balance was the Atlantic and Gulf Coastal Plains Aquifer, which stretches across the southeast coast and Florida.
While there is no eminent fresh water aquifer catastrophe (depending on one’s definition), it is a wake-up call especially for those who live in dry regions – that not only is surface water becoming scarce or non-existent in drought regions, but the aquifers themselves have become stressed and are depleting much faster than they are replenishing.
Most of you know that three days without water and you’re ‘toast’… right?
Source: http://onlinelibrary.wiley.com/doi/10.1002/2015WR017349/abstract