Most crops are grown with this thing called "rain" and without any supplemental water. Using just rain means they are part of the natural transpiration and precipitation cycle, so their unnatural water usage is 0.
A few days ago there was a post here about water now being traded as a commodity.
In many parts of the world, the water supply is far from guaranteed and must be shared with the local environment, population and other farmers. Using 1/250 of the water otherwise supplied by rain is pretty compelling.
And that's without the arguments about reducing the need for pesticides and fertilisers.
No, most crops are watered with dams and irrigation systems. It means changing the natural patterns for river areas, destroying ecologies, concentrating water to water-needy crops, destroying soil. Some plants do not store water, but vaporize it fast and it also can affect other plants and animals.
Somehow the water used by [almond and whatnot] farmers is a problem in CA.
Rain is great, and Earth's water cycle is closed, but plants evaporate water but you won't get it back as rain immediately.
Plus if you install irrigation you are taking water away from somewhere that would likely not evaporate that fast. (Eg from a river.) And if you also happen to have drainage, (eg if you converted a wetland area), then you suddenly discharge too much water from that region, and you won't get it back as rain.
I came here to dispute this, but when I looked it up, it appears to be true, at least in the US, where irrigated farms produce only 39% of farm products (in $). That being said, its still a nontrivial percentage, and irrigation for agriculture accounts for 80% of the nations water consumption.
Sure, but with the already significant climate changes yields are affected. Some regions turn toward irrigation, and it'll eventually run out, and it already affects non-agriculture water usage in many regions. (In India. But China's megacities also consume more water than what the natural replacement rate of the regional water table.)
I'm not saying everyone has to go all in on vertical farming, but there's value in food safety.
A few days ago there was a post here about water now being traded as a commodity.
In many parts of the world, the water supply is far from guaranteed and must be shared with the local environment, population and other farmers. Using 1/250 of the water otherwise supplied by rain is pretty compelling.
And that's without the arguments about reducing the need for pesticides and fertilisers.