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  • California is currently experiencing one of the most severe droughts on record, and new

  • NASA data says it's worse than we thought.

  • Hey guys, Amy here for DNews.

  • A drought is a natural hazard that develops slowly over time as a climate or environment

  • changes.

  • Water levels drop in the lakes and rivers that we draw water from, forcing reliance

  • on underground stores called aquifers, sources of fresh water that farmers also rely heavily

  • on, particularly in times of drought.

  • So what exactly is an aquifer?

  • An aquifer is a saturated rock that water can easily move through.

  • Typically these rocks are permeable and porous, though non-porous rocks like granite can be

  • aquifers if they're fractured enough to hold water in the free spaces.

  • This is where well water comes from; wells are drilled into aquifers so the water inside

  • the rock can be pumped out.

  • If the well goes dry, you just have to dig deeper and lower the water table.

  • Water flows into and eventually drains from an aquifer in a cycle, so each has a natural

  • recharge and discharge zone or zones.

  • The recharge zones typically lie at higher altitudes so water can flow down, but they

  • can occur wherever it's natural for water to move.

  • The discharge zones typically occur in springs and low altitude wetlands.

  • The other benefit of this groundwater is that the rock acts as a natural filter that traps

  • sediment and other nasty particles like bacteria so the water that flows from the spring is

  • beautifully clean and clear.

  • But aquifers can become contaminated, typically by humans.

  • Contaminants can flow into an aquifer from a natural or manmade pathway that drains into

  • the waterlogged rock.

  • And as NASA's GRACE mission is showing, these underground water stores are drying

  • up.

  • The GRACE mission uses two satellites flying in tandem to very accurately measure variations

  • in the Earth's gravity field.

  • Changes to ocean currents do affect gravity measurements.

  • So do movements of glaciers.

  • And so does the movement of ground water, so these satellites can see that aquifers

  • are actually drying up because the gravity in these areas is changing.

  • And it's a global thing.

  • Using GRACE data of 37 aquifers over the course of 10 years, scientists see that groundwater

  • is being rapidly depleted in the Middle East, North Africa and Central Asia, and in the

  • United States.

  • The aquifer under California's Central Valley is being badly overused.

  • Even aquifers in sparsely populated and wet areas like the Amazon Basin and the Great

  • Plains are doing a little better thanks to rainfall that replenishes the water stores.

  • That less water is available globally is starting to affect political relations.

  • Border issues in some parts of the world are becoming increasingly complex as fights break

  • out about access to water under those borders.

  • To learn more about how low water levels in aquifers is affecting inter country relations,

  • check out this video from Test Tube News:

  • And there's a link in the description below!

  • So wherever you are, it's time to start saving water!

  • Turn the tap off while you brush your teeth!

  • Don't linger in the shower because you're bored!

  • What little things do you guys do to save a few ounces a day?

  • Let us know in the comments below or on Twitter @DNews.

  • And of course, for more DNews every single day of the week, don't forget to subscribe!

California is currently experiencing one of the most severe droughts on record, and new

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