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A comment on Without Enough Water to Go Around, Farmers in California Are Exhausting Aquifers. Parent comment

Re:Without Enough Water to Go Around, Farmers in California ... by tzs on Saturday July 24, 2021 @12:20PM (#27942180)
99.995% of the water use to grow alfalfa ends up in the local atmosphere, to go wherever the winds and/or diffusion takes it presumably eventually coming back out as rain or dew somewhere.

Only 0.005% ends up actually in the alfalfa to be exported to wherever the exported alfalfa goes.

Similar for almonds. I don't know the exact amount, but an upper limit is 0.03% of the water exported with the almond, and 99.97% left behind in the local atmosphere or local ground. That upper limit comes from counting the entire mass of the almond as water.

There are legitimate grounds to criticize growing high water usage crops in regions that do not have enough water naturally, but exporting water is not one of them.

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Re:Without Enough Water to Go Around, Farmers in California ... by nextaccountic on Saturday July 24, 2021 @04:10PM (#27944049)
The issue here isn't physically exporting the water but exporting the externality. It's like investing in a heavily polluting industry is "exporting pollution" - the product itself contains trace of the pollution, but the local damage was done on behalf of the product.

I mean, once used this water ain't getting back to the aquifer anytime soon! If it were, we wouldn't be talking about aquifer depletion and there wouldn't be any concern regarding its use.

https://en.wikipedia.org/wiki/Overdrafting

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Re:Without Enough Water to Go Around, Farmers in California ... by Justin_K on Sunday July 25, 2021 @09:26AM (#27949014)
I'm sorry but moving ground water from below the surface to the local atmosphere means you are taking a limited resource and removing it from the area. In California, a desert landscape, evaporated water does not turn into local rain.
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Re:Without Enough Water to Go Around, Farmers in California ... by phendrenad2 on Saturday July 24, 2021 @02:00PM (#27943074)
I don't think the atmosphere is as "local" as you imply (diffusion of the water molecules should spread them out of state far faster than they can condense in-state).
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