12 Jan 2017 1.16"
Quite a bit of rain, with more on the way.
Of course the news has been full of receding drought concerns. A secondary news item that sometimes follows is that the drought is defined by surface water. This is the most important caveat.
Ground water usage and replenishment are not well measured, tracked, or inventoried, and what you don't know you have you can't keep track of. Measuring by ground level subsidence, we've kept withdrawals well ahead of replenishment for many years, a fact that is only now coming to light.
Sent from my iPhone at great expense
The GRACE satellite and similar ones make it possible to study the change in local gravity, which is mainly due to water mass changes. So, yeah, we're able to 'see' groundwater pumping on a large scale now. And we can see subsidence with SAR. Let's hear it for the GPS constellation, without which none of this is possible.
ReplyDelete