As pointed out in email

[james_davis_nicoll]

India’s declining fertility rate, now only slightly higher than that of the United States, is part of a global trend of lower population growth. Yet the media and many educated Americans have entirely missed this major development, instead sticking to erroneous perceptions about inexorable global population growth that continue to fuel panicked rhetoric about everything from environmental degradation and immigration to food and resource scarcity.

In a recent exercise, most of my students believed that India’s total fertility rate (TFR) was twice that of the United States. Many of my colleagues believed the same. In actuality, it is only 2.5, barely above the estimated U.S. rate of 2.1 in 2011, and essentially the replacement level.

Comments

[daveon.livejournal.com]

Ah... ok... not sure I think that will happen. I can see California having some water supply problems that are going to be, umm... costly... but I'd need a lot of convincing for something akin to what we might see elsewhere.

[mmcirvin.livejournal.com]

I can definitely imagine US grain farming being ruined in favor of Canada, which gets to add massive food exports to its resource-extraction economy.

[mmcirvin.livejournal.com]

...mind you, Canada already exports a fair bit of food. I mean compared to that.

[graydon saunders (from livejournal.com)]

Which we almost certainly can't do. To a first approximation, there isn't much usable dirt we're not using.

Anyone not concerned about pollinator availability needs to start paying attention; there's been a general, multi-decade decline in birds that prey on flying insects. Something's killing the flying insects. Major US crops -- almonds, for example -- are experiencing failures because of this. Not critical for grain crops but not trivial, either.

Last year's drought did a pretty fair job of hammering agricultural productivity and surpluses. It could pretty readily be a _wet_ year next climate ratchet. All it takes is a day over 45 C and you're not getting anything from that field this year. Random peaking like that is no longer sufficiently unlikely to be discounted on a wide scale.

[anzhalyumitethe.livejournal.com]

Graydon,

Based on all the models I have seen and its a nontrivial amount, the food supply for NorAm is secure. Whether we will need to continue price supports or have massive surplus for export, that remains to be seen. There will not be a problem, however, feeding all realistic population projections for everything north of the Isthmus of Panama.

The Midwest looks relatively stable, temperature wise compared to the coasts and arctic. Its even looking likely to have a net increase in precipitation. That will cause its own issues, of course.

Now the California central valley, though...

As for 45 C killing off agriculture, uh, no. I am aware of the Rubisco issues, but what we grow in Southern NM frequently gets over 45 C, yet, still we get crops. Second largest pecan orchards in the world, for that matter. I grew a garden there for my own consumption there, too.

A day? piffle.

[graydon saunders (from livejournal.com)]

I would very much prefer it if those models are correct.

Even assuming they're perfectly correct my worry isn't the average. It's the increase in the likelihood of a widespread severe heat event.

Temperature thresholds and crop production: a review, at
http://www.locean-ipsl.upmc.fr/~ESCAPE/luo2011.climaticchange.pdf

is a summary article; it is in accord with my recollection that you're just not going to get yield from a field crop (and yes, I didn't specify field crop! but three-fifths of food is rice and wheat and maize, and that's rather what I was thinking of) if it hits 45C for a day. I'd be very interested in _what_ you're growing in Southern New Mexico that copes with that kind of heat!

Pecans, arboriculture generally, given lots of water, I can see surviving better. But even there there's all sorts of issues with pollen and fruit setting and heat stress. (and cold stress. and just generally having the wrong cultivar for the weather you happen to get this year.)

What I'm seeing, in the middle of southern Ontario, meaning a wet, large-lake, mid-continent environment, is major crop losses; maple syrup, apples (both having years at ~one third regular yield), hay shortages, widespread stock reductions due to hay shortages, and near-total failure of maize crops and things like potatoes or mustard. Nothing dire; things move around, there's, in an ideal year, a large surplus so a non-ideal year isn't going to do anything but move food prices.

Convincing myself that will stay certainly so in what's a bad drought year next climate ratchet, I find very tough to do.

[anzhalyumitethe.livejournal.com]

What's grown commercially in SoNM? Corn, cotton, pecans, as noted, and, of course, chile.

What I grew just fine for myself: corn. cucumbers. tomatoes. zucchini and other squash. carrots. lettuce.

The beets didn't make it past sprouting and being good for salads though.

[graydon saunders (from livejournal.com)]

Beets do badly with heat way up here in the frozen north, so I'm a bit surprised you could get them to sprout!

So, poking around on Google, my supposition from that crop list that it's all irrigated is true. (It also looks like consistent productivity has been driving up both water use and the price of agricultural land.)

New Mexico as a whole gets more than half its irrigation water from "surface flow"; that's dependent on annual rainfall. (So's the aquifer, eventually.) If they've got enough water, transpiration can keep the plant cooler than the air temperature; if they don't, and that's in significant part a guessing game about how much water to apply based on how hot you think it's going to be for the next week (assuming you've got no worries about water supply...), you get reduced yields or crop kills.

It's certainly good that this isn't _usual_ but I don't see where the argument that this isn't a worry arises.

We're not actually arguing that heat _can_ kill plants here, are we? Everybody's seen a tree that's had an idling truck parked under it or next to it, and the foliage gone all brown and crinkled where the exhaust plume made the leaves too hot?

[scott-sanford.livejournal.com]

I will mention in passing that the Perennial California Water Shortage has been going on longer than many of us have been alive, and shows no sign of ending any time soon. But by the same token, it might not be getting particularly worse, either.

Much of the problem can be traced to two factors: plopping down major cities into deserts, and turning other deserts into irrigated farm land. Humans are unlikely to give up either Las Vegas or the Imperial Valley.

[mmcirvin.livejournal.com]

I remember hearing about 35 years ago that the next great national crisis after the Energy Crisis was going to be the Water Crisis. Every few years, somebody predicts an American civil war over it.

I eventually went out west and realized that over there it's the Water Crisis all the time. But it doesn't quite get to the shooting stage.

[scott-sanford.livejournal.com]

Hardly ever. (I think it did a few times in the Old West era.) But the water quotas have been over-committed to supplying more water than actually exists since at least the 1930s, and by now everyone's used to it.

Floridians panic when it snows. Minnesotans, not so much.

[carloshasanax.livejournal.com]

Graydon is kind of a nut. This is not as well known as it should be. I treat him like one. He doesn't like it. Too bad, so sad.

[mindstalk.livejournal.com]

So there's no reason to worry about possible widescale heat or drought events causing crop failures that markets can't compensate for, combining with a lack of Egyptian scale granaries that could have given us a few years of buffer?

[carloshasanax.livejournal.com]

Right, Damien. "No reason to worry" is almost exactly the opposite of "worry like an Internet crank like Graydon Saunders".