Originally posted at ClimateREALISM
By Linnea Lueken – March 31, 2022
Inside Climate News recently published an article discussing a new model which warns of an impending global food production drop due to climate change. Climate models have proven notoriously bad at describing reality, and data collected during the recent warming show crop production is regularly setting new records; the very opposite of the food production apocalypse Inside Climate News is warning of.
The article, “Complex Models Now Gauge the Impact of Climate Change on Global Food Production. The Results Are ‘Alarming,’” says that there is a looming climate-caused global food crash that is projected to occur sooner than previously believed. The research depends entirely on agricultural projection models that depend upon the outputs of unreliable climate change models to make their projections.
The paper, “Climate impacts on global agriculture emerge earlier in new generation of climate and crop models,” presents the projections of a series of model runs comparing different crops around the globe based on the most recent Coupled Model Intercomparison Project (CMIP6) climate scenarios.
It uses two climate models, or representative concentration pathways (RCPs)—RCP2.60, and the discredited RCP8.5. These models have been shown to run too hot, projecting rising temperatures that are, in the words of the scientists who work on the models, “implausibly fast.”
As discussed in a Climate Realism post, here, two recent peer reviewed studies found a large degree of bias towards warmer projections, and that the CMIP5 models warm 4 to 5 times faster than actual observed temperature data. McKitrick and Christy (2020) write in “Persuasive warming bias in CMIP6 tropospheric layers” that “[W]e see no improvement between the CMIP5 and the CMIP6 models.”
If the current models used for temperature prediction are not accurate, then the food production models that rely on them cannot be expected to be accurate either.
The United Nations Intergovernmental Panel on Climate Change’s (IPCC) Sixth Assessment Report relied heavily on these same temperature models, particularly the implausible RCP8.5, and has been widely criticized by scientists for doing so. Climate Realism discussed the recent report here, and found that the report contained a large amount of speculation and very little evidence based on measured data.
The authors of the study assert that even the high mitigation scenarios, like RCP2.6, will still cause global food production to “soon face fundamentally changed risk profiles,” which will necessitate adaptation and “risk management” in global farming practices.
Data, however, show that major food crops have enjoyed rising global production over at least the last 60 years, alongside rising carbon dioxide and modest warming.
As originally discussed in this Climate Realism post, here, The United Nations Food and Agriculture Organization (FAO) has collected food production data from around the globe since 1961. For the staple crops, corn, wheat, and rice, this data shows significant rises in both overall production and yield per acre as the earth warms (see figures 1 and 2, below).
Corn, in particular, is discussed in the paper and cited by Inside Climate News as being threatened by global warming. However, during last few decades of warming, the FAO reports world corn production has risen by approximately 467 percent, and yields by more than 196 percent.
An analysis by Willis Eschenbach in a Climate Realism post here, broke down major food crops by country and average annual temperature, and found “the yields in the warmer countries are no better or worse than the yields in the cooler countries.”
This finding, along with the FAO data, suggests that the alarmism surrounding hotter temperatures and food production is unfounded.
As the popular saying in computer science goes: garbage in, garbage out. It is irresponsible and unethical to use unrealistic runaway warming scenarios to promote the idea that billions will starve from a climate change induced collapse of food production. This is especially true when one considers, as explored in more than 100 Climate Realism posts, real world data demonstrate higher carbon dioxide concentrations and the warmer planet are regularly producing record yields.
https://www.heartland.org/about-us/who-we-are/linnea-lueken
Linnea Lueken is a Research Fellow with the Arthur B. Robinson Center on Climate and Environmental Policy. While she was an intern with The Heartland Institute in 2018, she co-authored a Heartland Institute Policy Brief “Debunking Four Persistent Myths About Hydraulic Fracturing.”
The absurd, shrill comments are all desperate propaganda to keep the narrative going as long as possible. They need those signatures for their green new deal-green tyranny/ great reset. They know that if the People wake up to the treachery and lies before the treachery is sealed, they are in big, big trouble.
It is up to US to induce people to question the narrative. They have to be led to wake themselves up.
As the Ukranian war (where alot of wheat comes from) and the supply chain problems increase, the cultural marxists/fascists that control the corporate media & “climate science” are getting in front of the game by blaming it on “climate change” instead of the real and obvious reasons.
“It uses two climate models, or representative concentration pathways (RCPs)—RCP2.60, and the discredited RCP8.5. These models have been shown to run too hot…”
This lady seems to have no idea about models. The RCPs are not models and do not run too hot. They don’t run at all. They are scenarios; one of a number of possible paths that someone thinks gas concentrations might evolve. The depend on future government policies, which are not matters that science can predict.
The global food production models are nothing like GCMs. They chose to use the RCP scenarios as their scenarios. That is the only connection. They could have developed their own.
I see WUWT has taken to describing RCP8.5 as “discredited”. You can’t “discredit” a scenario. The modelling process tells you that if some scenario happens, some climate result will follow. It makes no claim that any scenarios will happen; again that is for future human decisions. You can if you like decide that a scenario is so improbable that it is not worth calculating. But you can’t prove that it won’t happen, any more than you can prove that it will.
Model, scenario, prediction, projection, let’s call the whole thing off…
Oh yes you can call a scenario discredited when it is so wholly implausible and obviously little more than a “ramp up the fear tactic”. Junk science at its best.
Instead of doing the Mannistic shout down approach, why don’t you instead comment on why everybody’s models fail?
Waffle and deflection … yes you have a scenario RCP8.5 and when you run it into the climate models (pick any one) you get ridiculous answers. That is the meaning which she has simplified down for layman publication.
So now you take those ridiculous answers and you put then into another model and you are getting even more stupid answers. Nick will try the old switch and bait here because that is how he rolls and he will claim they are putting RCP8.5 into the food model. So lets cut that stupidity off at the pass because you can’t run an emission scenario directly into a food scenario they aren’t related in any way. You can only enter climate itself in as an input and that requires a translation of RCP8.5 into climate and as per above you get retarded answers when you try that on any model.
Bottom line nobody has a climate model that can turn RCP8.5 into something that puts out realistic output.
This is little more than semantics, Nick, and not one of your better interventions. I enjoy your participation here as an antidote to the many reflex, vacuous comments which now attend this blog. But you do have an annoying tendency to pick the nits (which I agree often deserve picking) while ignoring the major point at issue in the post itself.
I fully expect that in a warming world agricultural productivity will continue to increase, as it has done for most of warming period we have already experienced. In this context the models, projections, predictions, scenarios (and yes, I do understand the differences) are about as useful as a fart in a cabinet meeting.
Those can be an indication of the presence of one or more Slitheen
“This is little more than semantics, Nick…while ignoring the major point at issue in the post itself”
No, it is the major point. The point of the article is to lumber these food production models with the alleged failings of GCMs. But the supposed connection is the RCP, and she hasn’t a clue what it is. And the connection fails. Using the RCP does not invoke any GCM results. It just makes use of an existing story about what we might do to the gas makeup of the atmosphere. It saves them the trouble of writing down their own, but they could have.
The food production models may have failings, but that isn’t because of the scenario they use. The scenarios may be improbable, but that isn’t because of GCMs.
My reading is that the author does understand the distinctions you draw attention to, although perhaps the phrasing is a little cliumsy. But just consider the title of the work that she criticises –
“Complex Models Now Gauge the Impact of Climate Change on Global Food Production. The Results Are ‘Alarming,’”
The takeaway that most people will get from that is, that’s going to be a disaster unless we restrict our emissions, and they won’t be reassured by a caveat that these are only projections or scenarios. That’s wrong, and the models are to blame. They are indeed worse than useless, because they misinform policy. That’s the danger. Look at what’s happening in the real world, and see how dangerous a reliance on models of this kind can be.
The food production models are failing BECAUSE there is no realistic conversion of GCMs to Climate.
You are deliberately playing the stupid troll and avoiding the problem you can’t directly connect GCM’s to food production there is no basis for the connection other than a climate model and probably a soil model.
If you think there is some direct way to connect GCM’s to food production explain how … other than that this is all sophistry.
Exactly. Climate is more than just temperature.
When, where, and how much it rains is extremely important. The GCMs seem to have little skill in predicting precipitation.
Even the weather models don’t do a good job of predicting rain. Last weekend Yahoo news was predicting rain for Monday, Tuesday, and Wednesday. By Tuesday, after no rain, the forecast was changed to rain on just Wednesday; we got <1/4″ overnight. Last night, the forecast was for rain mixed with snow overnight. When I got up this morning, the back deck was damp, with no signs of snow.
My impression is that there is a much higher error rate with false positives than for false negatives. That is, it commonly fails to rain when forecast to do so, but rarely rains when it it is not forecast.
Sorry dude, you are wrong. Do you think these agricultural models bother looking up Tmax/Tmin for the globe and make their projections? They use the outputs of the GCM’s as shown by the IPCC and all use the global temperature increase as happening everywhere the same for the whole globe.
The only ag study I know of that is realistic actually used growing degree days across the U.S. so they could get an accurate regional picture.
See here: https://www.nature.com/articles/s41598-018-25212-2
Not good news when they didn’t or couldn’t use any kind of GCM output to get what they needed. It also points a much different picture than using a simple global increased temperature as a single variable. Crops do rely on things other than temperature you know. Rainfall, sunshine, length of season, fertilizer, etc.
reminds of the Ollie and Parker study in which they rejected GCMs as a basis for coastal planning
GCMs rarely survive any sort of contact with reality
Nick,
Firstly,thanks for your comments here.
They concentrate the thinking of many in response.
Next, as to the “alleged failing of GCMs”, the following is from Peter Landesman in “The Mathematics of Global Warming”,The American Thinker,November 30,2009-
“…No simplification of the [GCM] equations can accurately predict the properties of the solutions of the differential equations.The solutions are often unstable.
This means that a small variation in initial conditions will lead to large variations some time later.
This property makes it impossible to compute solutions over long time periods.
As an expert in the solution of non-linear differential equations,I can attest to the fact that the more than two dozen non-linear differential equations in weather models are too difficult for humans to have any idea how to solve accurately.
No approximation over long time periods has any chance of accurately predicting global warming….
To base economic policy on the wishful thinking of these so called scientists is just foolhardy from a mathematical point of view.
The leaders of the mathematical community, ensconced in universities flush with global warming dollars, have not adequately explained to the public the above facts.”
This recalls the TAR 3,(2001) statement, “Climate is a coupled,non-linear chaotic system and future predictions of climate are not possible”.
“They are scenarios; one of a number of possible paths that someone thinks gas concentrations might evolve. ”
However you try and waffle it away, all of this is based around models. Or are you saying they pluck these “scenarios” out of thin air? (I was going to suggest somewhere else they may have plucked them from, but modesty and good manners prevents me)
“Or are you saying they pluck these “scenarios” out of thin air?”
Well, yes. A scenario is just what it says, a story about what you think might happen. You probably wouldn’t try to quantify it if you didn’t need it for a GCM, but you could. In the original scenario, Hansen showed what would happen if you increased the rate of CO2 increase by 1.5% per year. He didn’t have any scientific basis for saying that, and he wasn’t predicting that it was going to happen. He looked at other scenarios too, each reflecting a “what if” approach to future decision making. Arrhenius had scenarios too, although he didn’t have a word for it.
Nick has just admitted that ALL of climate change “science” is plucked out of thin air.
Finally he realises 🙂
Do you still believe in the fairy tale you were told when you were a child, Nick?
lol this is just an outright lie, and a particularly stupid one
read Hansen’s Senate testimony, it says very clearly that each scenario is an EMISSIONS SCENARIO, with Scenario A labelled “business as usual”
he later states that he has “high confidence” that the temperature predictions will evolve according the to emissions scenarios
since we did not in fact drastically reduce (C) or level off (B) emissions globally, he was predicting Scenario A concentrations and temperatures would occur
https://www.sealevel.info/hansen1988_retrospective.html
the degree of deliberate deception here is astounding.,. Nick really wants you believe Hansen didn’t claim catastrophe was coming without massive emission reductions, even though that was literally the entire point of the hearing
but at least we won’t be surprised in 30 years when Nick’s successors claim the IPCC was never actually predicting anything either
correction, his “high confidence” statements seem to relate to other factors, not his predictions per se
A reasonable person wouldn’t present a scenario that was appropriate for Mars, when modeling Earth. It is deceptive to present a scenario (RCP8.5) that is possible, but improbable. One could present a scenario even more extreme than ‘8.5,’ but it would serve little purpose other than to scare people. Realistic scenarios should be accompanied by probabilities. While ‘8.5’ was originally intended to be “Business as Usual,” that assessment has been shown to be wrong. There is little excuse to continue to use it in light of what we now know.
Clyde, in fact the “business as usual” should have been changed to just along the balloon sonde level below Hansen’s low scenario. Except for the 2016 el Niño, there still hasn’t been notable temperature rise so far this century even with adjustments to temperature that were the maximum that they could decently get away with.
Children born at the beginning this century are graduating from college and they haven’t experienced any global warming to speak of. They may well begin to notice a global cooling trend.
.
“. He didn’t have any scientific basis for saying that”
Wooah, Nick!
You’ve just admitted that the predictions of thermal doom are based around science-free numbers plucked out of thin air.
Have we just witnessed a damascene conversion?
Welcome to the dark side Nick.
If a scenario is presented as a describing a plausible outcome in certain circumstances and it demonstrably doesn’t then it has been discredited.
Intelligent people that have studied the subject all know the CAGW narrative is a crock. Those who support it’s continuance are either on the payroll or subscribe to the neo-puritan fascist world view that humanity is a problem that needs to be eradicated.
You?
“demonstrably doesn’t”
You can only demonstrate by looking at what happened, afterwards. And since a range of scenarios was investigated, most will turn out to not be what happened. RCP8.5 is the most pessimistic of the scenarios used. But you can’t say it couldn’t happen. That is just refuting from incredulity, which is what the barrage directed at RCP8.5 amounts to. The point of investigating it is to show what would happen if everything is allowed to slide.
My understanding is that much of the RCP8.5 scenario assumes the emission of CO2 far in excess of what has actually happened, and far in excess of what is actually available. In other words, it is a scenario which HASN’T actually happened, and COULD NOT POSSIBLY happen.
RCP8.5 can’t happen. There i said it. It does not require belief. C02 is not the ultimate control of temperature on this planet. A slightly warmer planet will not cause the destruction they predict.
Have you told this to your congressperson? Have you mentioned that the IPCC summaries are not predictions and therefore shouldn’t be used for policy decisions at the present time?
The point of investigating it is to show what would happen if everything is allowed to slide.
And these boofheads are the bees knees in ensuring world food production doesn’t ‘slide’ are they? Have they ever stuck in a marketable crop anywhere in their lifetimes to earn a crust? No! Nothing! Zip! I’m supposed to take their ‘scenarios’ seriously for the millions who actually do all over the globe?
Hubris thy name is climate changer scenario maker and all they need is more fertilizer- House set to pass marijuana legalization Friday | The Hill
My RCP is that by 2050 days will be 18 hours long, not because the Earth will spin faster but because “it depends on future government policies“.
Be prepared, then, for shorter days. Because this might change your life.
Sorry Nick, without the “scenarios” to drive them the GCM’s wouldn’t do anything. They are forward models so they need something to forward model. The RCP forcing “scenarios” are the driver they are trying to model.
The “scenarios” are inputs to the models!
You are trying to make light of a problem. Like it or not the RCP’s end up with a global temperature PREDICTION for most folks. You can call it what you like but that is what most people expect it to be.
This is also the danger of emphasing a “global” temperature. It is not regional based yet SO MANY studies end up using the global figure it isn’t funny. IOW, it is assumed that everywhere on earth Tmax is going up by that amount or more.
You have seen enough regional and local temp graphs that show little to no warming to know that the global figure doesn’t apply everywhere. Why don’t climate scientists make known that isn’t true and the fact that in most cases it is not Tmax increasing as much as it Tmin.
Half truths are as much a lie as no truth. Quit trying to criticize those who accept the propaganda from climate science as the truth.
“Like it or not the RCP’s end up with a global temperature PREDICTION for most folks”
No, they end up with four very different predictions, one for each scenario. It’s obvious to anyone who thinks about it that what happens depends on how the scenario unfolds.
Poor Nick, you can see him desperately trying to somehow support these failed models, that even he must know are fake and totally unreliable..
These same people have been prostelising about food shortage for longer than even the climate scare, but yield and production just keep on climbing.
Yes, Nick, the models are a manifest failure.
You know it, Everyone knows it
And no amount of spinning like a twirling top is going to change that.
RCP8.5 envisions burning more coal than thought to even exist, so it is not all that plausible.
After finding out that models turned out to be 300% too hot for the average of the predictions, they should have made a new hot pathway that was ~⅕ the warming of the disgraced 8.5 ‘pathway’. It was created before the warming estimates proved to be impossibly beyond the confines of reality. That they didn’t adjust it accordingly puts their ‘work’ as far away from the application of science as you can get and categorizes temperatures they do so meticulously adjust in the same place.
Nick Stokes, who was at least an intelligent, numerate antagonist has brought himself low supporting use of the rcp8.5 AFTER average scenario proved 300% too hot measured against observations. I’ve even criticized Curry for diplomatically judging it only improbable. Gee do they not know that GISS’s modeler Gavin Schmidt blew the whistle on himself and colleagues saying “…models are running away too hot, and we don’t know why “. Surely if the dark side is walking this whole shiteree all the way back, you wouldnt think anyone in the business would feel they had to defend it.
Nitpick Nick Strikes Again!
“you can’t prove that it won’t happen”
climate science in 2022, folks
of course the actual reason to calculate the discredited RCP8.5 (as Roy has pointed out for ten years now, even the past GCM trendlines are laughable) is so that their left-wing patron politicians can wave around their scary numbers and demand we re-order the global economy
at this point these people’s disconnection from reality is so total they might as well be living on another planet
except of course for the fact they’re wasting trillions of dollars on this one
I see you quote a real ‘chestnut’ from Nick Stokes, re., the RCP8.5 scenario, “you can’t prove that it won’t happen”.
But, really, the prospect is much *worse* than that! Myself, I can’t even prove that some ‘Baba Yaga’ somewhere can’t magically triple, no, ‘quad-rouble’ the badness of the RCP8.5!
Beat that alarmists, or bury your heads in the sand, the world is practically dead already..
“these people’s disconnection from reality”
They’re not disconnected from reality. They don’t care about physical reality.
They care about vehicles to power. Green alarm is a convenient vehicle to power — now along with covid alarm.
Once they achieve police power, their fake concern will vanish like fog in the sun. Then they’ll turn around and imprison or kill all their erstwhile allies — experienced revolutionaries and protesting greens — as enemies of the state. Then lower the boom of police terror on everyone else.
Lenin did it. Stalin did it. Khomeini did it. They all do it. It’s St.O.P.
Ideology. It always deludes, it always galvanizes, it always demonizes, and it’s always the same.
And the modellers don’t seem to know about physics.
Or to know about physical reliability.
Always the silly word games
Of course you can discredit a scenario, especially if it’s preposterious.
They use the word “Complex” to describe the model so it must be good!
My simplistic view is that the author has clearly, but inadvertently, shown that the models are junk science as food productivity is at a higher level than it has ever been.
Watch what happens when food production and availability drops significantly as a result of the Russian invasion of Ukraine. When Ukraine’s wheat production falls and fertilizer scarcity causes productivity to fall throughout the world, listen to them shriek, “I told you so, I told you so, I told you so!”.
Ask any farmer….the biggest source of his improved grain production is fertilizer, and he hasn’t really noticed much improvement due to the “maybe” couple of extra growing days in the spring…..
The picture at the top of the story displays a bit of computer code (javascript) in which there is this:
Blur the bs button … just the thing a climate model needs.
It may be this code. And yes, it has nothing to do with how a climate model does its calculations … but it just looks so darn appropriate.
IIRC much of the increase in average temperature is caused by the increase in minimum rather than maximum temperatures.
Arable crops do not like cold temperatures, (why we use greenhouses for high value crops), and in my experience we have always had to wait for the soil to warm up in Spring before sowing maize (corn), and also winter wheat does not like cold frosty weather either.
What is often more important in determining yield is the provision of adequate moisture in the growing season, and as IIRC the forecasts are for a wetter climate then this would seem to be a plus factor.
As far as rice is concerned I have no experience, but can only surmise that as it currently grows well in hot areas of the globe it should not suffer if maximum temperatures are steady and with the provision of adequate water in the paddy fields.
What could affect crop output however is if vast areas of productive farmland is turned over to solar panels and wind generators in the drive to total electrification of our society.
I have never seen crops being grown in a solar park.
No, the food production crisis is being created by the POLITICAL LEFT and they have told us for DECADES that they were going to do exactly what they are doing!
Their position is a tricky one. They have to appear concerned about mass starvation while hiding their glee from hoping that it might come true.
At this point they don’t care that people see what they are and what they are doing.
Lack of fertilizer is the problem. Another reason to frack for natural gas!
Why is there a lack of fertilizer? Because the political left is destroying energy production across the globe. Why was fertilizer production pushed out of US? The political left used environmental regulation and nuisance lawsuits to drive it over seas. All these problems have a single source, the political left
Even if the world was warming, (as if), this would open up vast areas of land to farming and agriculture.
The one thing that could have most impact on food supplies is a drop in production of gas, hence insufficient fertilisers to cover the world’s crops.
If gas was unavailable in the future we could always return to coal for fertiliser nitrogen production.
In the 1960s ICI Agricultural Division at Billingham used 1000 tonnes of coal per day in their ammonia plant to produce ammonium nitrate, using steam reforming and Haber-Bosch process.
The ammonium nitrate plant was I believe first built to provide the raw material for explosives in WW2, and subsequently used to product NitroChalk, a mixture of AN and lime which was a granular product with 21% N content.
Subsequently the AN was produced in three plants designed by Kellogg, not the cereal company, to run on North Sea gas.
Until the new plants were fully commissioned the engineers nicknamed them Snap, Crackle and Pop after the breakfast cereal.
The ammonium nitrate from the new plants was then melted and sprayed down a cooling tower, similar to a lead shot tower, to produce prills that contained 34.5% nitrogen.
The price of AN fertiliser has risen this year from £300 per ton to £1000 per ton, if you can get it.
This adds about £140 per acre to the cost of growing wheat, and is hich results in about 2 tons per acre yield increase.
So this is responsible, if I have my calculations right, for a marginal increase of £70 per ton with a 2 ton yield response to the nitrogen fertiliser.
Equivalent to about 7p per large wholemeal loaf.
Quite silly, as corn is originally from subtropical Mexico, so some cultivars can definitely handle warmth.
Have any of these models/scenarios/predictions/fortune cookies factored in the loss of agricultural land required for solar panels and battery storage? It could/couldn’t/might/might not/may be/may be not make a difference.
The title of the actual paper : Climate impacts on global agriculture emerge earlier in new generation of climate and crop models
The headline of the media article : Complex Models Now Gauge the Impact of Climate Change on Global Food Production. The Results Are ‘Alarming’.
The link to the (paywalled) paper provides the now standard “with access token / can be read on your computer screen but you cannot download the PDF file” mode, which may be limited but is much better than nothing.
As usual, the associated “Supplementary Information (/ Material)” file is freely downloadable though.
Attached is a screenshot of “Fig. S1” from the SI file for the Jagermeyr et al (2021) paper.
NB : Those graphs are for the SSP5-8.5 (CMIP6) “pathway”, i.e. the “pessimistic / catastrophic” one out of the two they chose.
The Abstract from the original paper :
[ Scrolls through the Inside Climate News article again … ]
Words fail me …
So corn is the only crop that has a for sure fail?
What a joke!
A-maize-ing, isn’t it ?
Pretty corny joke!
Inside Climate News recently published an article discussing a new model which warns of an impending global food production drop due to climate change.
don’t they do this every year?
meanwhile…
https://ourworldindata.org/exports/average-corn-yields-in-the-united-states-1866-2014_v3_850x600.svg
I have more faith in climate models (which at least have predicted the temperature direction correctly, if not the scale) than in climate-based agricultural models. We’ve seen a steady stream of negative predictions, set against the real-world story of agricultural success. The only plausible threat to agriculture is removing fossil-fuel inputs. This sentence is truly remarkable:
—
The authors of the study assert that even the high mitigation scenarios, like RCP2.6, will still cause global food production to “soon face fundamentally changed risk profiles,” which will necessitate adaptation and “risk management” in global farming practices.
—
Necessitate adaptation? Perish the thought! What would agriculture be like if it had to adopt adaption and “risk management”? It would be modern agriculture! Any model that assumes no adaptation is more unrealistic than RCP 8.5.
Looking at the paper, figure 1 illustrates four crops: maize, wheat, soybeans, and rice. The agricultural models for SSP 126 (projecting 427 ppm in 2100) all have mean impacts of 10% or less. For SSP585 (projecting 1122 ppm in 2100) the impacts are dramatic for maize (mean -24.1%) and wheat (+17.5%), but trivial for soybean (-2.1%) and rice (+1.7%). If you trust the mean, only maize has an issue with unreleasticly high emissions scenarios. If you look at the range of food models use, you’ll see that all four crop types have positive and negative projections. For maize, the range goes from about +5% to -60%, for wheat from about +60% to -20%, for soybeans from +40% to -60%, and for rice from about +30% to -30%. Surely it’s only in climate science where the mean of a set of *widely varying* models is thought to have some sort of meaning.
And what sort of temperature change accompanying 1122ppm has brought about this dramatic impact on maize? Figure 2 shows the mean temperature change from 1983-2013 to 2069-2099, using region’s growing season. This amounts to +0.31C in all maize regions, but a dramatic +0.53C in the *best* growing regions. Wait, that’s not dramatic at all, is it. For such a dramatic impact, maize must be a fragile crop indeed, very sensitive to temperature variations from its ideal growing temperature. Who knew? Figure 3c shows maize impact on a world map, with the corn belt losing more than 20%, more than 30% on the high plains. But the corn belt has a wide temperature range from north to south — farmers won’t be able to adapt? Why not?
Don’t worry, they haven’t forgotten it, it gets a mention near the end of the Discussion section:
—
Cropping system adaptation can substantially reduce and even outweigh adverse climate change impacts, for example, by switching to other crops51 or better-adapted varieties52. Integrated into ISIMIP’s wider cross-sector activities, GGCMI will systematically evaluate farming system adaptation and changes in yield variability and extreme event impacts in subsequent efforts.
—
Good luck to their subsequent efforts, but for now we can be afraid that if we burn more fossil fuels than are known to be accessible and persist in growing the exact same crops in the exact same places, and the climate models turn out to be accurate for a change, we can expect maize yields to fall by 24%. Or maybe 60%. Or maybe it will go up by 5%. Who knows? After all, the two constants of climate science are “The science is settled” and “It’s worse than we thought.”
All in all, despite having zero confidence in the actual food projection models, I can’t say that their results are terribly alarming — even the ridiculous worst-case scenario only creates a substantial decline in one of four staple crops, and that’s without any adaptation at all. The ICN article talks of “millions of people could starve”, and points out the vast number of hungry or malnourished people today — as if that were a failure of modern agriculture rather than governments. As usual, the scientific article they are referencing is far less alarming than the spin ICN is putting around the issue. ICN does manage to mention CO2 fertilization:
—-
At the time, there was scant research on the intersection of climate change and agriculture, and what did exist—including Rosenzwieg’s own work—suggested that rising levels of carbon dioxide could have a “fertilizing” effect on some plants. That finding would ultimately become an enduring point in the effort to undermine climate science broadly—a “positive” seized upon by politicians and industry lobbyists as they sought to minimize the climate emergency.
But as the disciplines of crop and climate modeling evolved, they began to point more conclusively toward much more worrisome possible outcomes.
—–
Yes, more worrisome. See, the take from the paper can’t be wheat up, maize down. No, the real wheat story is that wheat’s projected benefit is *less than the previous generation of models*. As always, the science is settled and it’s worse than we thought. Though what’s particularly scientific about putting scare quotes around “fertilizing” when discussing CO2’s interaction with “some plants” escapes me — we didn’t need Rosenzwieg’s own work to know that carbon dioxide is plant food. Can’t have “politicians and industry lobbyists” seeking to “minimize the climate emergency”. Not when the very concept of a climate emergency is the result of frantic propaganda on the part of politicians and industry lobbyists. ICN’s own existence benefits from the perception that there *is* an emergency.
But the impact papers, like this one, fall well short of emergency, let alone the “existential threat” that President Biden and others proclaim without pushback. In this paper there’s discussion of when the climatic effects will actually be detectable, which gives you an idea at how much of a climatic emergency in food production there has been — indeed, the modern warming period has corresponding with the greatest agricultural revolution in historic times, I find this to be common with other impact papers I have read; whenever I am able to dig into the details, alarming press releases subside into a variation of “the much richer world of the future will be slightly less rich than it would have been given constant climate.”
I missed that on my first “quick skim” of the paper (see “screenshot” attached to this post).
Model outputs :
– Maize (/ Corn) : SSP1-2.6 a bit bad, SSP5-8.5 (really) really bad
– Wheat : SSP1-2.6 a bit good, SSP5-8.5 even better [ Journal editors : Shhhhhh ! ! ! ]
– Soybeans : SSP1-2.6 a bit good, SSP5-8.5 a bit bad
– Rice : SSP1-2.6 a bit good, SSP5-8.5 (slightly) less good
Concluding sentence of the Abstract :
– – – – –
Note to moderators : I think the screenshot is covered by generic “fair use” and “public interest” clauses.
Please remove this post if that turns out not to be the case !
If I had an investment advisor who only managed to get the sign of the slope of the growth of my investment correct, but predicted 3X the growth I actually received, I’d look for another advisor.
We are facing a likely food shortage in the near future for other reasons – they’re just getting the narrative in place so they can say “see I told you so”
also remember, these crop projections are typically based in “no adaptation” assumptions
even though farmers spend all year painstakingly deciding what to plant next year and how best to grow it (irrigation, fertilizer, etc)
similar logic shows that if no one uses their brakes for the next hour, there will be millions of car accidents
but that’s not a very good argument for lower speed limits
anyways historically higher global temps are typically linked to higher, not lower, global biomass production, including ag, for all the obvious reasons
“new model which warns of an impending global food production drop due to climate change.”
Linnea, a good analysis of our burgeoning harvests, but you have to keep your eye on the pea. The new model is part of an old cynical strategy by the totalitarian wing of climate doomists. The West’s destructive interference in the oil and gas industry, financing and markets by their climate policies, disruptive regulations, and defunding efforts has caused huge shortages and rocketing prices.
This effects not only high farming costs, and mining costs for P and K fertilizers but an acute shortage and prohibitive costs for nitrogen fertilizers which are made using natural gas. These model guys just want to get ahead of the parade. Agronomists have already predicted the terrible food shortages. The Russian invasion of Ukraine has made it worse, but it was already locked in before the invasion.
Any change in food production will come as a result of the Russian Invasion of Ukraine and not as a result of any imaginary. or even real. Climate Change.
Maybe they are really basing their projections on the expectations of sharply reduced fertilizer production due to natural gas shortages and widely spread manufacturing and distribution disruptions