Global Warming to bring biblical insect plague

From the UNIVERSITY OF VERMONT and the “plague of locusts” department

Global warming: More insects, eating more crops

Global loss of wheat, rice and maize projected to rise 10-25 percent per degree of warming

Crop losses for critical food grains will increase substantially as the climate warms, as rising temperatures increase the metabolic rate and population growth of insect pests, according to new research.

“Climate change will have a negative impact on crops,” said Scott Merrill of the University of Vermont, a co-author of the study published today in Science. “We’re going to see increased pest pressure with climate change.”

The research team looked at how the insect pests that attack three staple crops – rice, maize and wheat – would respond under a variety of climate scenarios. They found that rising global temperatures would lead to an increase in crop losses from insects, especially in temperate regions. Losses are projected to rise by 10 to 25% per degree of warming.

Just a 2-degree rise in global average temperature will result in total crop losses of approximately 213 million tons for the three grains, the researchers say.

Insects like it hotter – up to a point

The losses will come from an increase in insect metabolism, and from faster insect population growth rates. The link with metabolism is straightforward. “When the temperature increases, the insects’ metabolism increases so they have to eat more,” said Merrill, a researcher in UVM’s Dept. of Plant and Soil Science and Gund Institute for Environment. “That’s not good for crops.”

The link with population growth, however, is more complex. Insects have an optimal temperature where their population grows best. If the temperature is too cold or too hot, the population will grow more slowly. That is why the losses will be greatest in temperate regions, but less severe in the tropics.

“Temperate regions are not at that optimal temperature, so if the temperature increases there, populations will grow faster,” said Merrill, an ecologist who studies plant-crop interactions. “But insects in the tropics are already close to their optimal temperature, so the populations will actually grow slower. It’s just too hot for them.”

Key grain crops to take a hit

According to the study, wheat, which is typically grown in cool climates, will suffer the most, as increased temperatures will lead to greater insect metabolism, as well as increased pest populations and survival rates over the winter. Maize, which is grown in some areas where population rates will increase and others where they will decline, will face a more uneven future.

In rice, which is mostly grown in warm tropical environments, crop losses will actually stabilize if average temperatures rise above 3°C, as population growth drops, counteracting the effect of increased metabolism in the pests. “Rice losses will taper off as the temperature rises above a certain point,” said Merrill.

That means that the most substantial yield declines will happen in some of the world’s most productive agricultural regions. “The overall picture is, if you’re growing a lot of food in a temperate region, you’re going to be hit hardest,” said Merrill.

“I hope our results demonstrate the importance of collecting more data on how pests will impact crop losses in a warming world — because collectively, our choice now is not whether or not we will allow warming to occur, but how much warming we’re willing to tolerate,” said Curtis Deutsch of the University of Washington, who co-led the study with Joshua Tewksbury, director of Future Earth at the University of Colorado, Boulder.

France, China and the United States, which produce most of the world’s maize, are among the countries that are expected to experience the largest increases in crop losses from insect pests. France and China, as major producers of wheat and rice, respectively, are also expected to face large increases in losses of those grains as well. “The areas that produce the most grain, especially wheat and corn – the US, France and China – are going to be hit hardest,” said Merrill.

Reduced yields in these three staple crops are a particular concern, because so many people around the world rely on them. Together they account for 42% of direct calories consumed by humans worldwide. Increased crop losses will result in a rise in food insecurity, especially in those parts of the world where it is already rife, and could lead to conflict.

As farmers adapt to a changing climate by shifting planting dates or switching to new cultivars, they will also have to find ways to deal with pests, by introducing new crop rotations, or using more pesticides. But not all of these strategies will be available to all farmers. “There are a lot of things richer countries can do to reduce the effect, by increasing pesticide use or expanding integrated pest management strategies,” said Merrill. “But poorer countries that rely on these crops as staple grains will have a harder time.”

###

Of course, the press release and study apparently assumes static pest management practices. Meanwhile yields don’t seem to be affected by bugs:

0 0 votes
Article Rating

Discover more from Watts Up With That?

Subscribe to get the latest posts sent to your email.

190 Comments
Inline Feedbacks
View all comments
tty
August 31, 2018 9:01 am

Simple to verify. Annual temperature in San Antonio is 18 degrees C warmer than in Edmonton. Summer temperatures are 12 degrees C warmer, so insect losses in Texas should be 120-300% alternatively 180-450% greater. If degrees F is intended multiply by 1.8.

It would seem that agriculture is actually impossible in Texas, though nobody has noticed.

H.R.
Reply to  tty
August 31, 2018 10:43 am

tty, has anyone told the farmers around San Antonio that they are doing the impossible? Someone should clue them in.

Joe - the non climate scientist
Reply to  H.R.
August 31, 2018 1:32 pm

Have you ever seen corn grow in Texas.

North of Dallas, the corn is generally dead brown by the second week of june every year. never seen green corn growing after the last week of june in this neighborhood

H.R.
Reply to  Joe - the non climate scientist
August 31, 2018 4:19 pm

Not much for he insects to go after, then. 😜

I had a great-uncle who grew corn and had a pecan grove on his farm outside of Halletsville, Texas, and my Grandfather was a sharecropper near Victoria, Texas. I don’t recall what their insect worries were. The insects probably died from the heat.

rocketscientist
Reply to  tty
August 31, 2018 2:14 pm

And pollinated by bees that can’t fly.

The one question that should be asked more than any other, by any reputable researcher who believes they have found some new truth, is: “Does this make sense?”

MarkW
August 31, 2018 9:05 am

Insects like it hotter.

So do the things that eat insects.

D. Anderson
August 31, 2018 9:06 am

Dude! Where’s my DDT?

MarkW
August 31, 2018 9:10 am

“will result in total crop losses of approximately 213 million tons”

What percentage of all crops does that work out to?

Dale S
Reply to  MarkW
August 31, 2018 11:04 am

Using information off google for 2016/7 season, that would be a bit less than 10% of the current combined wheat, rice, and maize production. If the projection were accurate, and production remained static despite nearly quadrupling in the last fifty years, that would certainly be a significant impact if not necessarily a catastrophic one. But imagining that grain production will remain constant (aside from insect losses) in a warming, higher CO2 world doesn’t strict me as a good foundation for policy. Locusts aren’t the only lifeforms that might benefit from a mild warming in temperate zones, and plants benefit *directly* from higher CO2.

Joel Snider
Reply to  Dale S
August 31, 2018 12:16 pm

‘Stasis’ is one of those environmental fictions.

tty
August 31, 2018 9:11 am

Another interesting thought. The three primary cradles of civilization and large-scale farming were:

The lower Nile Valley (Egypt)

Sourhern Iraq (Sumer) and Khuzistan (Elam)

Punjab and the Indus valley (Indus civilization)

What do these areas have in common? They are among the very few places on Earth where summer temperatures regularly top 50 C.

Bob boder
August 31, 2018 9:19 am

Has there been an increase already?
If not then you can calk this up to another story that verifies there has been no significant temperature increase globally.

DocRock
August 31, 2018 9:21 am

but wait, the available area for these crops will be increased into current cooler climatic areas. so no net change as the crops will still be harvested in the same temperatures as they are now..

H.R.
Reply to  DocRock
August 31, 2018 4:24 pm

Thweet! Thweet!
“15 yard penalty from the spot of the foul for pointing out the obvious! Still remains first down.”

markl
August 31, 2018 9:28 am

“Losses are projected to rise by 10 to 25% per degree of warming……Just a 2-degree rise in global average temperature will result in total crop losses of approximately 213 million tons for the three grains, the researchers say.” What a crock pulled out from where the sun don’t shine.

Neo
August 31, 2018 9:30 am

In my area of Pennsylvania, there is a outbreak of Spotted Lantern Flies.
These lantern flies go after fruit, causing a number of local wineries to stop growing grapes.
The source of the outbreak … somebody in Berks county imported ornamental stone for their garden from VietNam 4 years ago. The stones were not properly cleaned or inspected.
So far, there are no natural predators, so this year they are everywhere.

They especially like to put their egg masses on the Ailanthus altissima, commonly known as tree of heaven, but they have also been going after our Silver Maples.
We have been using a shop-vac with an extended tube to vacuum the little buggers off the nearby trees.

Bob boder
Reply to  Neo
August 31, 2018 9:41 am

time to get some bats from vietnam

rocketscientist
Reply to  Bob boder
August 31, 2018 2:19 pm

May I suggest you read a copy of the children’s story titled, “The King, the Mice and the Cheese”.
Short read, but a worthwhile concept you seem to have missed.

Roger welsh
August 31, 2018 9:32 am

Who is paying whom to produce unsubstantiated threats!

Chris
August 31, 2018 9:57 am

So let’s see – the yield as a percentage of production is declining rapidly, but according to WUWT, there’s no problem. Cognitive dissonance in action!

MarkW
Reply to  Chris
August 31, 2018 10:32 am

Actually it isn’t, but keep telling yourself you are correct, and eventually you will be.

Chris
Reply to  MarkW
August 31, 2018 10:57 am

I read the graph, Mark. What are you up to now, 50,000 posts with no links? A Guinness record!

MarkW
Reply to  Chris
August 31, 2018 1:02 pm

It doesn’t take much fake data to get your little heart a pounding.
The graph is a projection, it isn’t happening. If the model is right, it might happen.

Might happen is not the same as is happening. Though I’m not surprised that you aren’t smart enough to figure that.

BTW, I do at least as many links as you do.
Though I’m not surprised that you keep up with that lie. It’s not like you have anything real to fall back on.

Joel Snider
Reply to  Chris
August 31, 2018 10:45 am

‘Projected’. As in virtual reality. Where warmists live.

MarkW
Reply to  Joel Snider
August 31, 2018 10:49 am

Given the many problems already pointed out with the so called study, there is no reason to assume that what was “projected” will actually occur.

Chris
Reply to  MarkW
August 31, 2018 11:05 am

Mark, what are the many problems you are referring to?

MarkW
Reply to  Chris
August 31, 2018 1:02 pm

Once again, Chris demonstrates that his college degree was in cluelessness.

rocketscientist
Reply to  MarkW
August 31, 2018 2:30 pm

MarkW,
You make assumptions that may not be warranted. 😉

rocketscientist
Reply to  Chris
August 31, 2018 2:29 pm

Chris,
You might actually want to read some of the comments already set forth. They innumerate many shortcomings of this latest divination.
If you do not pause to ask “What could be wrong with the conclusions in this study?” therein lies your problem.
Stop accepting and start thinking!

Chris
Reply to  rocketscientist
September 2, 2018 10:08 pm

Rocket – if I say a particular study has a number of issues, I’m quite happy to enumerate them. If I’ve already done so, I will then point out where I posted that. But saying “just read 200 comments and fine the issues yourself” is a lame and lazy response. This is how Mark rolls. It’s always generalisms such as “the scientists are corrupt” “the data has been corrupted” etc.

RACookPE1978
Editor
Reply to  Chris
September 2, 2018 10:48 pm

Chris, replying to rocketscientist

It’s always generalisms such as “the scientists are corrupt” “the data has been corrupted” etc.

OK. Name the climate science data that has not been corrupted (er, edited/revised/changed) by the government’s self-selected, self-called “climate scientists”

Dale S
Reply to  Chris
August 31, 2018 10:50 am

Cognitive dissonance is reading comments that point out the (truthful) information that grain yield has consistently been *increasing* during the modern warming period, and refuting it with an *invented* claim that yield “as a percentage of production” is declining rapidly.

Chris
Reply to  Dale S
August 31, 2018 10:57 am

Hey Dale, what’s your explanation for the increasing gap?

Dale S
Reply to  Chris
August 31, 2018 11:06 am

Pretty simple — they are different metrics. Production is in millions of tons. Yield is in production *per hectare*. You can’t take one as a “percentage” of the other.

Dale S
Reply to  Dale S
August 31, 2018 11:17 am

And since you missed the true significance of the yield line, here it is — yield is up, WAY up, during the modern warming. This isn’t just from the warming, even though, like locusts, temperate grains tend to benefit from a slightly warmer world (and also higher CO2). It’s also from other improvements in modern agriculture, including improvements in pest control.

Positing that yield will be static from now on, with the exception of increased insect losses, is a highly unrealistic thought experiment. As a claim that crop yields *will* suffer, it should be taken with several metric tons of salt.

Chris
Reply to  Dale S
August 31, 2018 11:32 am

I didn’t miss a single thing. Explain why the gap between production and yield is widening, not shrinking (or staying constant). It’s a simple question, Dale.

Bob boder
Reply to  Chris
August 31, 2018 12:55 pm

Chris

It is a simple question and he already answered it, the problem is not how simple the question is it’s how simple the questioner is

MarkW
Reply to  Chris
August 31, 2018 1:19 pm

Chris, not liking an answer is not the same thing as the answer being wrong.

When you graph two entirely different things, it’s hardly unusual that the slopes aren’t the same. You shouldn’t need a link to figure that out.

Production is yield per hectare multiplied by the number of hectares in production. If the number of hectares in production does not stay constant, then the two lines will not have the same slope.

That should be simple enough for even you to understand.

Dale S
Reply to  Chris
August 31, 2018 2:20 pm

Chris, as I already said, and MarkW elaborated on, they are different things. Production is a *function* of yield and acreage. The visual “gap” is widening, not shrinking, because the acreage in production is slightly increasing, not decreasing. Since the lines are scaled to 1961 output, if acreage in production had remained exactly the same, there would be no visual gap at all between yield and production at all.

If you had understood that, and “didn’t miss a single thing”, you never would have attributed cognitive dissonance to those who looked at the graph and saw no problem — because there *is* no problem. The “rapidly increasing” visual gap is a product of what’s being graphed and how it’s being graphed, no more, no less. It has literally *nothing* to do with losses to insects (or anything other kind of losses) at all.

The real significance of plotting the yield is that it shows the dramatic increase in production since 1961 is *mostly* the result of yield improvements, not additional acreage. In truth, if all else is equal expanding acreage should cause yield to *fall*, since the added acreage is likely to be of lower quality than the acreage still in use.

Since yield has nearly tripled during the warming we’ve seen since 1961, it seems implausible that increased losses from insects, if they happen, of 10-25% per degree would outweigh continued advances in agriculture.

And of course, since we have had warming in recent decades, I’m disappointed that they don’t give us the obvious — how much *insect-related losses* have actually changed over that timespan. A google search doesn’t quickly show any statistics in that area, what little there is seems to concentrate on post-harvest losses, which isn’t exactly hungry locust territory.

The article is paywalled, but the visible intro claims that 5% to 20% is currently lost to insects — that’s a *very* wide spread, and doesn’t necessarily exclude post-harvest losses. But even if we assume a current 5-20% loss in *yield* from insects, and accept the author’s model that an increase of 1C will cause *losses* to increase by 10-15%, then a further degree of warming would move the current 5-20% loss (already subtracted from yield) to a 6-23% loss instead–a net loss of 1% to 3%. This is (obviously) *tiny* compared to the massive increase in yield we have actually seen and are continuing to see.

But suppose they really meant 10-15% decrease in *yield*, not insect losses? In that case, they need to explain how in the ~1C increase we’ve *already had*, insect losses can be at 5-20% if the 1C increase *by itself* should’ve taken 10-15%. Since their commentary also makes it clear the effect they expect is concentrated in the temperate regions, they should also be aware that in the industrialized temperate regions losses to insects are much, much lower.

Chris
Reply to  Dale S
September 1, 2018 1:32 am

MarkW said: “When you graph two entirely different things, it’s hardly unusual that the slopes aren’t the same. You shouldn’t need a link to figure that out.

Production is yield per hectare multiplied by the number of hectares in production. If the number of hectares in production does not stay constant, then the two lines will not have the same slope.”

DaleS said: “Chris, as I already said, and MarkW elaborated on, they are different things. Production is a *function* of yield and acreage. The visual “gap” is widening, not shrinking, because the acreage in production is slightly increasing, not decreasing. Since the lines are scaled to 1961 output, if acreage in production had remained exactly the same, there would be no visual gap at all between yield and production at all.”

You can’t say I didn’t give you guys a chance to retreat from your position. But no, you doubled down. Look at the graph, and look at the lowest plot. It’s cereal land under production index. The acres under production is about the same now as it was in the early 1980s. Perhaps a percent or 2 different, but that is nothing compared to the increase in gap between production and yield. The minor changes in acres under production cannot explain the widening gap between production and yield.

Let’s make a more recent comparison. Acreage has increased by about 5% from 2000 to 2014. The gap between production and yield in 2000 was 60. By 2014, despite only a 5% increase in acreage under cultivation, the gap has grown to 100. The increased gap between production and yield is far greater than can be explained by a 5% increase in acres under cultivation.

Dale S
Reply to  Chris
September 1, 2018 3:45 am

Chris, we doubled down because we not only can look at a graph and see the pretty pictures, we can also read the text and understand the words. As you’ve been told repeatedly, production is a *function* of acreage and yield. That means the “gap” between the two is also a function of acreage and yield.

So for example, suppose the relative yield increases from 225 to 275 while the relative acreage increases from 110 to 121 over a period of 15 years. The relative production will go from 247.5 to 332.75, changing by 85.25 while the yield increased by only 50. That’s obviously a much larger growth than 10% (the acreage change). But that’s only if you’re looking at the raw size of the gap instead of the ratio. 247.5/225 = 1.10, and 332.75/275 = 1.21. The *ratio* between relative production and relative yield went up by exactly 10%, precisely as it *must*, because production is *defined* as the product of yield and acreage.

So if you’re concerned about the “widening gap” in terms of absolute numbers instead of as a percentage of production, your answer is that it is widening *because* yield is increasing dramatically. But if you look at the gap as a ratio of absolute production, it is increasing entirely because of the increase of acreage. And in neither case is the “gap” physically meaningful to any issue in the OP, because the two lines are *different things* measured in different units that happen to be plotted on the same graph — what unit do you imagine the gap is? You might as well be alarmed by the rapidly increasing “gap” between production and land use.

Do you get it yet? It was kind of you to “give us a chance to retreat from our position”, but no retreat is necessary. If you still don’t understand, perhaps you could now explain what *you* think is the “problem” illustrated by the “gap” between the two. What I don’t understand is how you can expect me to take your alarmism seriously when you fail to understand the very definition of yield and production even when it’s been explained to you repeatedly.

BTW, the source of the graph at https://ourworldindata.org/yields-and-land-use-in-agriculture has a lot of fascinating graphs. It will also let you look at the same graph by country. For example, if you look at the United States, you’ll see that the acreage used for grains compared to 1961 has actually decreased, and the yield line (as it must be) is actually above the production line. This should also be a cautionary tale to anyone who believes that a theoretical reduction in yield in the United States would *necessarily* reduce in a loss of production — putting more land into production, if necessary, would be easy. The same thing is true in the EU. China has had nearly constant land usage, so their yield and production lines are (as you would expect) very close together. Meanwhile, if you look at “Heavily Indebted Poor Countries”, the land use line is actually above the yield line — their increased production is driven much more by increased land use than increased yield. If you’re actually concerned about “food insecurity”, the real issue isn’t a small increase in temperature or a substantial increase in plant-friendly CO2 concentrations. The real issue is that poor countries haven’t been able to take advantage of the dramatic fossil-fueled yield increases we see in more developed countries. Discouraging them from industrializing and making fossil fuels more expensive is precisely what you should NOT do if you care about either food production or the loss of forest to agriculture.

Chris
Reply to  Dale S
September 1, 2018 11:56 am

Dale, I made it clear I know that production is a function of both acreage and yield/acre. You understate the increase in production that occurred relative to yield in your example. You chose figures of 225/275 for yield, and 247/332 for production. So let’s look at the graph. If we pick the times when the yield went from 225 to 275, the production went from 280 to 380. That’s an increase of 100, not the 75 in your example. And of course the land under cultivation did not increase by 10% during that period, the increase was closer to 8%.

And if we take the 2 years I just mentioned, 1980 and 2000, there is zero impact from greater land under cultivation. In 1980 the production was 180. In 2000 it was 280. The gap is 100. The yield went from 160 to 215, a gap of 55. And that’s with land under production flat.

So your statement “But if you look at the gap as a ratio of absolute production, it is increasing entirely because of the increase of acreage.” is false. The gap between production and yield widened considerably between 1975 and 2000, even though the cereal land under cultivation declined.

Dale S
Reply to  Chris
September 1, 2018 2:28 pm

Chris, yield is *defined* by production divided by acreage, it simply can’t be anything else. If the graph is inconsistent with that equation, there is a problem with the graph — it’s physically impossible for some issue to somehow reduce yield *without* having the same effect on production. That’s why there is no physical significance in any gap, widening or not, between production and yield. My example in going from 225/275 was not meant to specifically match up with the graph, it was showing how looking at the size of the gap is not useful.

However, you are correct that there does seem to be an issue with the graph. Comparing 1975 and 2000 on the world graph

1975: Production Index 163, Yield Index 146, Land index 109.49. 1.0949*146 = ~160, so generally inline but not a perfect fit.
2000: Production Index 277, Yield Index 220, Land index 107.38
1.0738*220 = 236, so a major discrepancy. So what happened? Did the definition of yield change between 1975 and 2000? Of course not. And the extra digits on only *one* of the indices seems suspicious. Checking the CSV file listed as the source for the graph, it has both “World” and “World” with a country code of OWID_WRL. Here’s the values for “World” (without country code) in those years:

1975: Production Index 165, Yield Index 135, Land Index 123
1.23*135 = 166.05, so it’s consistent with calculation
2000: Production Index 242, Yield Index 181, Land Index 134
1.34*181 = 242.54, so it’s consistent with calculation

These are internally consistent numbers but don’t match the graph.
They don’t match the OWID_WRL numbers:

1975: Production Index 163, Yield Index 146, Land Index 109.4887967
2000: Production Index 277, Yield Index 215, Land Index 107.3814152

That’s clearly the source for the graph, but is not internally consistent, and having the land index extend to seven digits after the decimal while the other indices are rounded is most suspicious — I doubt the Land Index is from the same source as the Production/Yield indices, which would be a very odd choice but explain the inconsistency. A brief look through the country entries shows that their land entries are all rounded (and I would be shocked if they weren’t consistent).

Now if your objection all along was that something was wrong with the *graph*, then you are vindicated. But I rather got the impression that you thought the graph illustrated some *issue* relevant to the OP that skeptics were ignoring. If the “World” figures are correct instead of the OWID_WRL World numbers, the yield increase is not as dramatic, peaking at 255 in 2012 instead of 275 in 2014 (unsurprisingly, the peak year had substantially less land in production). The land use increase is far more dramatic, peaking at 172 in 2014 (just getting past 171 in 1996). Peak production is at 407 in 2013, so the graph actually *understates* the production increase in grains since 1961 using that set of numbers.

But the claim that world yield has dramatically increased during the modern period is certainly true using any set of numbers, and anyone who compares the posited predator effect in the OP to the vast increase in production is certainly justified in thinking that increased predation of 10-15% per degree C of warming is not likely to be a critical issue.

Chris
Reply to  Dale S
September 2, 2018 10:13 pm

Dale – friends of mine own apple, pear and cherry orchards. They told me production is what is harvested, yield is what you have after tossing out fruit that cannot be sold (bird damaged, insect damaged, worm damaged, or not visually appealing). The “tossing out” function does not just occur during harvest, but also during packing. If that is an incorrect definition, than I stand corrected by you.

If that is the case, that production = yield x area under cultivation, then the graph is clearly very, very off. And it’s surprising that a graph with that egregious of an error would get published – but you never know!

Dale S
Reply to  Chris
September 3, 2018 8:25 am

Chris, I can’t speak to how your farmer friends use the term. My grandfathers both farmed and I worked on my Grandad’s farm for a few summers, he used “yield” as a synonym for production in the context of the farm — not because he was likely unaware of the formal statistical definition but because words can have different meanings in English. (BTW, he had very little post-harvest wastage in grains, since “visually appealing” doesn’t matter a whit to wheat or barley. Post-harvest insect losses are most common in developing countries. You do have post-harvest losses in grains while shelling, threshing, and milling, but that typically doesn’t happen between the time the grains go in the farm silo and the grain being sold to the mill or processor.)

Still, the graph itself clearly stated that yield was indexed to kg/hectare, so the information was right there to tell you it wasn’t using your friend’s definition — and that describing yield as a “percentage” of production was as nonsensical as describing average speed as a “percentage” of miles travelled. Plus, you were told what the definition was — repeatedly. And in the context of agricultural statistics, as opposed to ordinary spoken usage, I’ve never heard yield used any other way.

If you had gone to the website that the graph originated from, you would’ve also seen a formal definition of yield in section III, Data Quality and Definitions:

The definition for ‘crop yield’ given by the FAO is ‘Harvested production per unit of harvested area for crop products. In most of the cases yield data are not recorded but obtained by dividing the production data by the data on area harvested. Data on yields of permanent crops are not as reliable as those for temporary crops either because most of the area information may correspond to planted area, as for grapes, or because of the scarcity and unreliability of the area figures reported by the countries, as for example for cocoa and coffee.’

Yes, there’s a problem with the graph, at least for that dataset. The graph isn’t “published” as such, it’s an interactive graph that you can switch between the many data sets in the source. Even for that dataset, it’s not clear that it is “very, very off”, merely inconsistent. The likeliest case is that one of the three indices (production, yield, acreage) is wrong, and of those three it is the acreage that is most suspicious. But unlike the spectre of increasing predator loss, the dramatic increase in grain yield in recent decades is well-known and well-demonstrated.

MarkW
Reply to  Chris
September 1, 2018 7:24 am

When Chris gets his hand on a good lie, he just can’t let it go.

Chris
Reply to  MarkW
September 1, 2018 11:24 am

And, as usual, MarkW adds nothing but snark to the conversation. No effort whatsoever to dive into details. Zero. Just his usual fluff.

Bob boder
Reply to  Chris
September 2, 2018 7:45 am

Chris again you clues look up yield, it’s the amount of food produced per hectare. That’s food you know what people eat.
Production is total grains produced I.e. including the grains we don’t eat, you know feed, bio fuel and so forth and the stuff for food. Meaning we don’t have food problem because our production is greater than are food requirements.
Oh yeah that also means the yield per hectare is understated as far as production is concerned.

tty
August 31, 2018 9:58 am

Probably they haven’t yet noticed that the Rocky Mountain Locust hasn’t been seen since 1902 and is now officially extinct. In the eighteenth century it did cause damage as far east as Vermont.

The High Plains Locust last erupted in 1934-40 and is now rare, but it might conceivably stage a comeback if climate once again becomes as hot and dry as it was during “the Great Drought”.

DaveW
Reply to  tty
September 1, 2018 10:14 pm

Supposedly they flew into Grasshopper Glacier and froze to death, the Rocky Mountain Locust that is, or aliens or whatever. There is an interesting book on them I read a long time ago. Too early for CO2, but if the Satanic Gas melts all the glaciers, what will save us from the next locust plague? (This is sarc.)

Coeur de Lion
August 31, 2018 9:58 am

I love the ‘approx 213 mtons’ or whatever. That includes 214 and 212 etc ?. Three sig figures? These are scientists? Give them more money.

August 31, 2018 10:12 am

Crops and bugs aren’t grown in a “global” climate. At best they are grown in a regional climate and probably something even smaller. Since when did the so-called models become accurate enough to allow analyzing on a regional or smaller area for a future time? Heck, they can’t even tell us what the winter is going to be in the Midwest USA with any certainity and it’s only a couple of months away! This isn’t science, it is alchemy or worse prognostications from a medium.

August 31, 2018 10:27 am

Right. As if they could predict such thing. As if… https://compphys.go.ro/chaos/

Bruce Cobb
August 31, 2018 10:33 am

Invasions by space aliens will also have a negative impact on crops. You know those crop-circle thingies? Think tens of thousands of them. They like landing among crops, no one knows why.

RicDre
Reply to  Bruce Cobb
August 31, 2018 11:06 am

“They like landing among crops, no one knows why.”

Maybe they’re hungry.

Bruce Cobb
Reply to  RicDre
August 31, 2018 11:49 am

Or maybe, that’s what they WANT us to think.

RicDre
Reply to  Bruce Cobb
August 31, 2018 12:02 pm

“Or maybe, that’s what they WANT us to think.”

To Serve Man?

https://en.wikipedia.org/wiki/To_Serve_Man_%28The_Twilight_Zone%29

Gamecock
August 31, 2018 10:36 am

Nature is just going to ignore more insects and allow it?

No birds in Vermont? No frogs and toads? No dragonflies?

Temperature is surely NOT the limiting factor for insects.

Bitter&twisted
August 31, 2018 10:51 am

And of course, according to these “experts”, farmers will not take any proactive measures against increased (if it does happen) pest activity.
How does this pseudoscience get published?

prjindigo
August 31, 2018 10:56 am

As a certified pest control operator I can assuredly say that the article is accompanied by a picture of birds.

I choose to take this as an ironic sociopolitical commentary on the subjective idiocy of the actual paper.

graham dunton
August 31, 2018 10:56 am

What An abundance of chocolate coated protein!

Edwin
August 31, 2018 11:03 am

Some of these papers sound like they come from a bunch of scientist sitting around the local bar pontificating and fantasizing about their favorite and latest environmental gloom and doom scenario. Some of them, like this one, make the scientists involved, supposedly experts, sound like they haven’t got a clue about what they are talking about and do not really think too deeply about anything.

Just like “emerging” diseases most of the spread of agricultural pest in the last several decades had nothing at all to do with climate change. Like emerging diseases (e.g., Zika), emerging agricultural pest have almost all been due to modern very rapid transportation and failure of government to properly control what is crossing the border.

ResourceGuy
August 31, 2018 11:12 am

The Puritans are back! They were somewhere in VT all along.

Greg Woods
August 31, 2018 11:13 am

No, actually the insects will starve to death, as the crops in the future will have less nutritional value…

ferdperple
August 31, 2018 11:15 am

Simply amazing. Global warming will harm all the positive aspects of human life while helping all the negative aspects.

This makes global warming unique. Among all the forces of nature none are so selective. Only the 5th force, the force of human caused global warming has proven itself so selective.

ResourceGuy
August 31, 2018 11:17 am

What, no connection to maple syrup and ski seasons in VT? Or is that in the further study section?