A hidden ocean? So it's like a cave system or is it just a huge water table?
Ten times the amount of water found in all five Great Lakes is no drop in the bucket either.
But, as they say, you always find something in the last place you look.
Also in Africa.
I don't think it's caves, but I'm not sure what the alternatives to that are. Aquifer? Wet sand?
The means whereby they are estimating the amount strike me as very indirect. I wouldn't be surprised if other teams came up with quite different estimates as time goes by.
In any event, I don't think this water is easily usable by people. The main interest here is it's function as a "carbon sink."
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