Groundwater recharge rates might be underestimated in models compared to observed data, according to a new study.

Groundwater recharge rates might be underestimated in models compared to observed data, according to a new study.

Put simply, given how much we rely on groundwater for our municipal, agricultural and industrial water needs (HINT: it’s a lot!), it’s important to know how much we use versus how much gets put back into aquifers from snow and rain. When those numbers don’t match up, our water system gets out of balance and we experience water shortages.

In Global Recharge Data Set Indicates Strengthened Groundwater Connection to Surface Fluxes, study authors found that:

• Climate strongly shapes the fraction of precipitation that will recharge groundwaters;
• This is likely more recharge globally than existing hydrological models suggest; and
• More groundwater must contribute to evaporation and streamflow than represented by current global models and water cycle diagrams.

That first bullet is an important one. From an Eos article about the study:

“The research team produced an updated model of groundwater recharge using a recent global synthesis of regional groundwater measurements. They found that a single factor, climate aridity, accurately estimated how much precipitation trickled into groundwater across the globe: Arid locations had lower recharge rates than humid ones.”

Given the increasing aridity and ongoing mega-drought in the Southwestern United States, this finding has great significance for even a water-rich place like the US. Studies like this help get water managers a long way down the path toward more effectively managing the country’s water resources to ensure there is enough for all of us.

[Eos]

Find out more about exactly how much freshwater we have available to us and why we're facing increasing rates of water scarcity in this presentation, "Beyond the Water Cycle: Teaching About Water Footprints."