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How a Solar Revolution in Farming Is Depleting Groundwater

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Re: How a Solar Revolution in Farming Is Depleting Groundwater

#81

Post by WithinReason »

schneems wrote: post #13

I’m very naive in this space. What percent of water extracted makes its way back into the water table and how long does it take? I assume you lose some to the plant that is harvested and some to evaporation. But how much makes it back?

FTA: "Irrigation is responsible for around 70 percent of the global underground water withdrawals, which are estimated at more than 200 cubic miles per year. This exceeds recharge from rainfall by nearly 70 cubic miles per year."

So 65% makes it back.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#82

Post by throwaway11460 »

WithinReason wrote: post #79
throwup238 wrote: post #65

Earlier quoted context omitted.

The American equivalent is the dust bowl. The ancient equivalent is the desertification of Mesopotamia. Etc. etc. Humans are bad at long term thinking.

Which species is good at long term thinking?

Many animals move on before they destroy the fields and return later once it's regrown.

Probably not much thinking but this is how your species survives. Perhaps humans think too much.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#83

Post by nonoesp »

> In theory, switching from diesel or electricity to PV pumping should eliminate greenhouse gas emissions. But in practice, farmers often use their solar pumps to supplement existing pumps, rather than replacing them. And, however it is pumped, the extra water available will also encourage farmers to adopt more intensive farming methods, using more fertilizer and machinery to grow thirstier cash crops, increasing the carbon footprint of the farm.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#84

Post by vasco »

nonoesp wrote: post #83

> In theory, switching from diesel or electricity to PV pumping should eliminate greenhouse gas emissions. But in practice, farmers often use their solar pumps to supplement existing pumps, rather than replacing them. And, however it is pumped, the extra water available will also encourage farmers to adopt more intensive farming methods, using more fertilizer and machinery to grow thirstier cash crops, increasing the…

When given the chance of reducing your footprint or improving your life, is it that surprising this is the outcome? Specially in developing countries.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#85

Post by Tade0 »

slavik81 wrote: post #76
no_wizard wrote: post #58

Earlier quoted context omitted.

What about the birth rate collapse[0] and how this affects things? It’s easy to project out with holding population levels but as the oldest among us die in the next 20-30 years there will be significant drops in population worldwide, before factoring other forms of population decline it’s already naturally going to happen. I wonder how this factors into all this. [0]: https://www.economist.com/leaders/2023/06/01/glo…

Is there any reason to think that the birth rate collapse is a long-term phenomenon (e.g. one thousand years)? There will presumably still be some subcultures that will have high birth rates, and I imagine they will make up an increasingly large proportion of the population as time goes on. There's a lot of noise about the population decline for 2100, but I wonder about 2200 and beyond.

Education of women is the strongest predictor of falling birth rates - this in turn is unlikely to reverse without a huge change in our economical system.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#86

Post by ajb »

bongodongobob wrote: post #60
TrainedMonkey wrote: post #56

Earlier quoted context omitted.

Please show the math and sources, I would love to see the sauce.

Me too because that sounds impossible to calculate.

What difficulty do you see? It's not going to be enough to appreciably change the ocean area, so isn't it just volume divided by the area of the ocean?

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#87

Post by neurostimulant »

Gibbon1 wrote: post #42
leros wrote: post #36

I know some farmers in North Texas where they are pulling water out of a depleted aquifer. The water is starting to get salty so they're adjusting to salt tolerant variants of their crops. The ground is also starting to drop due to the aquifer draining. It's crazy to see

In the Santa Clara Valley farmers pumped enough water out of the ground in the early 20th century the ground dropped a dozen feet in some areas. Bad thing too is that once an aquifer settles like that it's carrying capacity is permanently reduced. Also in southern California there is a fair amount of previously productive farm land that is salted up and useless. That'll happen to the north Texas farmers you've mentio…

It's odd that foreign media reporting the Indonesian government plan to move the seat of government from Jakarta to Borneo as primarily motivated by the sinking of Jakarta (it affects the northern part of Jakarta, while the goverment is mostly operating in Central Jakarta), while the other more important (to the government) reasons are usually under-reported, such as to reduce the java-centric development, improving the government's efficiency by moving various government agency closer together instead of scattering everywhere over the huge megacity with traffic jams everywhere, and improving the government image because foreign diplomats will arrive in a pristine, green city instead of concrete jungle with bad air and traffic jams everywhere.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#89

Post by pfdietz »

qwerty456127 wrote: post #88

What's the state of technology in producing fresh water from sea water? Isn't there any serious progress making it more efficient and cheap?

It's become progressively cheaper through incremental engineering improvements. The cheapest way is generally reverse osmosis, especially on water that is just brackish.

But it's also generally cheaper (per unit of saved water) to just use water more efficiently. Agricultural water use can be enormously economically inefficient in the US.

Re: How a Solar Revolution in Farming Is Depleting Groundwater

#90

Post by boxed »

WithinReason wrote: post #79
throwup238 wrote: post #65

Earlier quoted context omitted.

The American equivalent is the dust bowl. The ancient equivalent is the desertification of Mesopotamia. Etc. etc. Humans are bad at long term thinking.

Which species is good at long term thinking?

Termites are pretty good. It's too expensive for them to rebuild their nests all the time so they don't destroy their surroundings.
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