The Two Degree Limit

By Andy May

For decades We have been told that we must not let global warming exceed two degrees Celsius above the “pre-industrial” global average temperature. Recently the IPCC lowered this limit to 1.5°C. In the latest IPCC report, called AR6, pre-industrial is defined as before 1750, but they use global temperatures from 1850-1900 as representative of the period because global average surface temperatures are not available for 1750.[1] The U.S., Europe, and much of Asia were industrialized by 1900, so their numbers are clearly not representative of the period of interest, unless temperatures remained constant from 1750 to 1900, which is unlikely.

Why the focus on 2°? In a 2014 comment in Nature, David Victor and Charles Kennel tell us that there is little scientific basis for the 2°C figure, but it was a simple focal point and it “sounded bold and perhaps feasible.” (Victor & Kennel, 2014). Then they admit the goal is “effectively unachievable.”

What is the “pre-industrial?” Did it have an ideal climate that we wish to return to? The year 1750 was in the coldest and most miserable part of the Little Ice Age (LIA). The LIA was the coldest period in the Holocene Epoch, or since the last glacial period ended about 12,000 years ago, at least in much of the Northern Hemisphere.

Figure 1. Rosenthal, et al. temperature reconstruction of the 500-meter water in the Makassar Strait, Indonesia. Source: (Rosenthal, Linsley, & Oppo, 2013). For full size, click here or on the figure. The present-day temperature shown is from the Makassar Strait Argo data collected by the University of Hamburg from 2006-2016 at 500m (Gouretski, 2019).

Figure 1 shows a proxy reconstruction of the water temperature at 500 meters in the Makassar Strait of Indonesia. In the strait, the 500-meter water generally flows from the Northern Pacific Ocean to the Indian Ocean and the temperature represents North Pacific temperatures, with a minor contribution from the Banda Sea (Rosenthal, Linsley, & Oppo, 2013). It is similar in shape and amplitude to the various Greenland ice core temperature reconstructions (Figure 2). The reconstructed temperatures are compared to a modern (2006-2016) average 500-meter temperature (the red box) from an analysis of Argo data by the University of Hamburg (Gouretski, 2019).

Figure 2. Various Greenland Ice Core temperature reconstructions. The Vinther reconstruction in black is preferred (Vinther, et al., 2009).

For more details on the Rosenthal reconstruction see here, for more details on the various Greenland ice core reconstructions see here. The Greenland ice sheet has grown and shrunk a lot over the past 12,000 years and the resulting elevation changes have affected the Alley temperature reconstruction shown in light gray in Figure 2. For this reason, the elevation corrected reconstruction by Bo Vinther, shown with a thick black line is preferred (Vinther, et al., 2009). In addition, Figure 2 shows another modern reconstruction from 2000BC to 2000 by Kobashi (Kobashi, et al., 2011).

Both Figure 1 and Figure 2 show a distinct Little Ice Age low temperature, that occurs between 1600 and 1850. All the reconstructions show the Little Ice Age is about three degrees cooler than the Holocene Climatic Optimum, from 8000BC to around 4000BC. Greenland and the North Pacific lie in the Northern Hemisphere, which has a unique temperature history. Figure 3 compares the Northern Hemisphere to other latitude slices, all the slices are 30° of latitude, except the tropics which is from 30°N to 30°S. The Northern and Southern Hemispheres cover 60°N/S to 30°N/S, and the Arctic and Antarctic slices are greater than 60°. Notice that over long periods of time the Antarctic temperatures move in the opposite direction to Northern Hemisphere temperatures.

There are a total of 29 temperature proxy records used to make the curves in Figure 3, and over half of them are in the Northern Hemisphere or in the Arctic. There are seven in the tropics and only three in the Southern Hemisphere and three in the Antarctic. The coverage is very sparse, so sparse it is hard to draw any conclusions about global average temperature from this data. That said, we can look at proxies in a specific location and tell when temperatures at that location were warmer or colder, we can even estimate by how much. Willie Soon and colleagues discuss how to evaluate temperature proxies properly in two 2003 papers.[2]

It is helpful that Rosenthal’s reconstruction shows about the same temperature profile as the best Greenland reconstruction, that is Vinther’s. They differ in detail, as one might expect and they are thousands of miles apart, but in general they tell the same story.

Figure 3 suggests that most climate change takes place in the Northern Hemisphere between 30°N and 60°N. Temperatures in the tropics don’t change much and Antarctic temperatures tend to move in the opposite direction from the Northern Hemisphere and vary less. Even the Arctic varies less than the Northern Hemisphere, as defined here. Only the tropics, the Arctic, and the Northern Hemisphere show a Little Ice Age, but they bottom at different times. Antarctica warms during the Little Ice Age, and cools after.

Figure 3. Temperature reconstructions by latitudinal slice. The Antarctic is 90°S to 60°S, Southern Hemisphere (SH) is from 60°S to 30°S, and the tropics is from 30°S to 30°N. The Northern Hemisphere follows the same pattern. See here for more details. Click on the image to enlarge it.

For this post, I only need to point out that in the North Pacific and Greenland, we have likely seen temperatures three degrees warmer than the pre-industrial period (aka the Little Ice Age) during the Holocene Climatic Optimum from 7500BC to 4400BC. This is the time period that saw the birth of human civilization.

We also saw high temperatures during the so-called Minoan Warm Period about 1600BC, prior to the collapse of the Bronze Age civilization around 1200BC, due to cold and drought. The cooling after the Minoan Warm Period, lasted from around 1200BC until about 700BC. During this miserable period, called the Greek Dark Age, Mycenean civilization collapses, the Hittite Empire falls, and there were severe droughts in the U.S., India, Europe, Africa, and China.[3]

Little Ice Age

The Greek Dark Age was cold and miserable, but nothing like the bitterly cold, dry, and stormy Little Ice Age, also known as the “pre-industrial” period that the IPCC measures climate change from.

The cold spells that frequently occurred during the pre-industrial period caused humanity many problems. Paul Homewood as well as Wolfgang Behringer’s excellent book, A Cultural History of Climate, and an article by Geoffrey Parker offer us a lot of historical examples. All over the world most glaciers reached their maximum Holocene extent during the Little Ice Age. In Chamonix, France advancing glaciers swallowed entire villages.

There was no summer during 1675, and it was the second coldest summer in the past 600 years in North America according to proxy evidence. The winter of 1657-1658 was particularly brutal. Massachusetts Bay and the Delaware River both froze over, allowing people and deer to cross on the ice. The Baltic Sea froze so hard that horses and loaded wagons could cross from Gdansk, Poland to the Hel Peninsula over 10 miles north of the city. Yet, the following summer was excessively hot in Italy and Greece. In India the monsoon failed that year, resulting in a devastating famine.

Between 1660 and 1680, more typhoons struck southern China at Guangdong Province, than at any other time in recorded history. In 1666, a hailstorm hit England and some of the hailstones were a foot in circumference, the size of softballs.

An enormously destructive hurricane hit the Caribbean Islands of Guadeloupe and Martinique in 1666 that resulted in 2,000 deaths and the destruction of a shore battery with walls 6 feet thick, as well as numerous ships.

Egypt in the 1670s had many very severe winters and people began to wear fur coats, something that had never happened in Egypt before. In the 1680s, the Sahel in Africa suffered a severe drought and Lake Chad reached the lowest level ever recorded.

The winter of 1691-1692 was very severe, starving wolves entered Vienna, Austria and attacked men and women on the streets. All the canals in Venice froze over and the mouth of the Nile River was choked with ice for a week. The cold of the 1690s caused a major famine in northern Europe and half the population of Finland died, as well as 15% of the population in Scotland. The Scottish famine was an important factor in its forced union with England. Mixed in with the cold years were occasional summers of intense heat and drought, such as the summers of 1693 and 1694 when the heat was unbearable in both England and Italy.

In 1715 a devastating hurricane struck the Bahamas and Florida killing between 1,000 and 2,000 people. That winter it was -20°C in Paris. There was a frost fair in London on the frozen Thames that year, with bonfires roasting oxen, carriages driven on the ice, and ice skating. The Little Ice Age was one of, if not the stormiest period in the Holocene in Europe, according to a study by Susana Costas and her colleagues.[4] So much for the argument that extreme weather is increasing in modern times, it is not.

Is the two-degree limit meaningful?

According to Der Spiegel, Germany’s past Environment Minister, Norbert Röttgen, said in 2009 that if the two-degree limit were exceeded, “life on our planet, as we know it today, would no longer be possible.”

Der Spiegel calls this scientific nonsense. They claim that the father of the two-degree limit was Hans Joachim Schellnhuber, director of the Potsdam Institute for Climate Impact Research (PIK). Schellnhuber tells them that he estimated average global temperatures since the rise of Homo sapiens and decided from proxy data that over the past 130,000 years global average surface temperatures were never more than two degrees higher than before the beginning of the industrial revolution. This became the two-degree limit proposed by the European Council of environment ministers in 1996. The limit is arbitrary and speculative, and contradicted, at least in the Northern Hemisphere, by the data we show above. Currently Schellnhuber admits that keeping global warming below two degrees is not feasible. He shows no data that suggests 2° of warming is dangerous, he just attempts to show it is unusual.

Prior to 1900, data from the Southern Hemisphere and oceans is extremely sparse, and prior to 1850, there are only six proxy temperature records south of 30°S and the whole Earth only has 29. How does he know that the global average surface temperature did not exceed two degrees Celsius? The short answer is, he doesn’t. Estimating global average surface temperature before 1900 is speculative, and before 1850, virtually impossible, there just isn’t enough good data.

Ice cores and other temperature proxies are not very accurate, dating the observations is problematic, but as a general approximation of annual to multidecadal temperature at a specific location they are OK and likely in the ballpark. We can be comfortable that temperatures in Greenland and in the North Pacific, near the Makassar Strait, were three degrees warmer than during the Little Ice Age (pardon me, I mean the “pre-industrial”) between 6,000 and 10,000 years ago, at least most of the time.

Yale Professor and Nobel Prize winner William Nordhaus probably first suggested the two-degree limit in 1977 (Nordhaus, 1977). Nordhaus uses the same logic that Schellnhuber used. He speculates that the maximum global surface temperature over the past 100,000 years was two degrees higher than in the late 19th century, so we should not exceed that. The problem is neither Nordhaus nor Schellnhuber know how much global surface temperatures have varied before 1850, and no one else does either. No one has any data that suggests two degrees of warming is dangerous for humanity or the environment.

The world is historically very cold and has been cold for millions of years, as can be seen by the Smithsonian Institute proxy reconstruction of the past 500 million years shown in Figure 4. This is still a proxy temperature reconstruction and has the same caveats mentioned above and the temporal resolution is very poor, since each point represents over five million years, but it is the best we can do. It shows the global average surface temperature for the past 500 million years is about 20-21 degrees Celsius, thus, currently, we are over five degrees below average.

Figure 4. Smithsonian estimate of global average surface temperature for the Phanerozoic, the past 500 million years. Source: (Scott & Lindsey, 2020).

Figure 4 was created using ideas developed by Chris Scotese, who also participated in the construction of the figure.[5] Scotese has shown that the global average temperature is closely related to the equator-to-pole temperature gradient because equatorial temperatures don’t vary much over time, but polar temperatures do. Thus, warming of the entire Earth, is mainly a function of warming at the poles.

Temperature proxies that can be traced into the distant past only exist in a few places around the world. Proxies are not thermometers, and their relationship to past temperatures, especially thousands of years ago is a bit speculative. These proxies are sometimes sensitive to only one season, usually summer. Currently temperatures are rising much more quickly in the winter and at night. Winters are warming at twice the rate of summers and, as a result, the climate is milder now than in the late 19th century. In the same way, nights are warming faster than days, again making the climate milder. Finally, temperatures in the Arctic are rising much more quickly than in the rest of the world, including the Antarctic. This is arguably a very good thing for Siberia, Canada, Scandinavia, and Alaska. Figure 5 shows Earth’s warming from 1979 to 2019. The equatorial region shows minimal warming, the Southern Hemisphere shows almost no warming, with some areas actually cooling, and the Arctic and Eastern Europe have warmed quite a lot.

Figure 5. Warming from 1979 to 2019. Source: NASA. Click on the image to enlarge it.

The impact of “global” warming depends upon where you live and what the past temperatures were.


In short, the two-degree limit has no scientific basis, it is an artificial political goal, meant to frighten the public into doing something. In a long and confusing paper, Jeroen van der Sluijs, et al. argue that artificially constructed political goals, like climate sensitivity or the two-degree limit, are political “anchors.” These are oversimplifications of a complex scientific topic that can help politicians energize a confused public into doing something, even if the scientific literature does not support it, or is too difficult to understand.

David Victor and Charles Kennel (Victor & Kennel, 2014) call the two-degree limit “wrong-headed.” As they point out, and Der Spiegel agrees, whether climate change is dangerous or not, depends upon where the observer resides. Any climate change is bound to be beneficial in some places and a problem in others.

Reto Knutti and colleagues write that the two-degree limit was a political decision, and that no scientific assessment ever recommended a particular target. Policymakers like to hide behind scientific evidence, demand actionable science, and claim to make science-based decisions, but Knutti, et al. argue that their approach is like a salad bar — they simply pick and choose (and fund) politically convenient studies, rather than a proper, balanced search for the truth. They continue:

“This 2°C warming target is perceived by the public as a universally accepted goal, identified by scientists as a safe limit that avoids dangerous climate change. This perception is incorrect: no scientific assessment has clearly justified or defended the 2°C target as a safe level of warming, and indeed, this is not a problem that science alone can address.”[6]

We evolved and currently live in an ice age that began millions of years ago. The Holocene Epoch, which began 11,700 years ago, is only the latest of many warm periods (Interglacials) in this ongoing ice age. For a complete list of the interglacials of the past 2,000,000 years, see Figure 4 here. Ultimately, the planet will return to a glacial state. At that time, as well as now, humans must adapt to climate changes, and what we must do to adapt depends upon where we live.

Global mitigation of climate change is not possible, there is no well-defined solution for everyone. Local adaptation is the best solution, and this is regardless of the cause of the changes. As for the hysterical politicians, like AOC, declaring we are all going to die from climate change, forget it. We will not,[7] as long as the oceans exist, the overall average surface temperature of the Earth is capped somewhere below a comfortable 30°C (86°F). Nothing to worry about here folks.

Download the bibliography here.

  1. (IPCC, 2021, pp. SPM-5, TS-11, TS-28)

  2. (Soon & Baliunas, Proxy climatic and environmental changes of the past 1000 years, 2003) and (Soon, Baliunas, Idso, Idso, & Legates, 2003b), also see (May, 2020c, pp. 49-86)

  3. (Cline, 2014, p. Kindle location 3237)

  4. (Costas, Naughton, Goble, & Renssen, 2016)

  5. (Scotese, Song, Mills, & Meer, 2021)

  6. (Knutti, Rogelj, & Sedláček, 2016)

  7. (Newell & Dopplick, 1979) and (Sud, Walker, & Lau, 1999), as well as many others (see Richard Willoughby’s posts here and here)

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July 19, 2022 10:08 am

Ideal climate to these lunatics is 20C everywhere at the same time during the day, 10C at night, rain only when you need, no droughts, no deserts, sightseeing glaciers.

You get the picture

Reply to  Pauleta
July 19, 2022 11:17 am

Camelot lyrics

It’s true! It’s true! The crown has made it clear.
The climate must be perfect all the year.

A law was made a distant moon ago here:
July and August cannot be too hot.
And there’s a legal limit to the snow here
In Camelot.
The winter is forbidden till December
And exits March the second on the dot.
By order, summer lingers through September
In Camelot.
Camelot! Camelot!
I know it sounds a bit bizarre,
But in Camelot, Camelot
That’s how conditions are.
The rain may never fall till after sundown.
By eight, the morning fog must disappear.
In short, there’s simply not
A more congenial spot
For happily-ever-aftering than here
In Camelot.

Camelot! Camelot!
I know it gives a person pause,
But in Camelot, Camelot
Those are the legal laws.
The snow may never slush upon the hillside.
By nine p.m. the moonlight must appear.
In short, there’s simply not
A more congenial spot
For happily-ever-aftering than here
In Camelot. Last Update: December, 02nd 2013

Bruce Ploetz
Reply to  Ed Reid
July 19, 2022 3:59 pm

Ironically the nearly mythical legends of Arthur probably arise from the cold period that also pushed the Romans out of Britain and engendered massive “climate refugee” hordes of Northmen into Europe.

The classic version of the legend includes a “winter without a spring”, attributed to an apocalyptic mythical war but probably really just a half-remembered distortion of the real environmental disasters of that time.

History practically pauses in that time period, not because nothing happened. Because it was so hard to find food and avoid the plagues that no-one had time to record it.

Yet they call it “Camelot” and sing about the climate.

Craig from Oz
Reply to  Bruce Ploetz
July 19, 2022 8:11 pm

“A year passed. Winter changed into Spring. Spring changed into Summer. Summer changed back into Winter, and Winter gave Spring and Summer a miss and went straight on into Autumn.”

July 19, 2022 10:13 am

The climate scam depends on ignorance of the geologic record. Their pretend reality has no substance.

Reply to  Gyan1
July 19, 2022 10:35 am

Basically, what we have here is called a reprieve.

The real question, which is more concerning, “when does this temporary warming trend end?”

Reply to  Gyan1
July 19, 2022 2:51 pm

Not true.
Historical climate data are not very important for the climate howlers.

Especially before the 1970s, after which CO2 levels and the global average temperature had a strong positive correlation.

They could not care less about the era of 100% natural climate changes. A mere 4.5 billion years !

They don’t even care much about 1940 to 2020 global warming
except for the fact that it happened (after 1975).

Their predictions are for future warming 2x to 3x faster
than in the 1940 to 2020 period. They PREDICT faster global warming than ever before. To scare people.

Reply to  Richard Greene
July 20, 2022 11:27 am

“Historical climate data are not very important for the climate howlers.”

My exact point. Ignoring inconvenient data is their MO.

Tom Halla
July 19, 2022 10:30 am

I have read enough history to conclude the LIA was a disaster overall.
Further, the proxies for temperature are not that precise. The Romans grew wine grapes in England, and the Norse were able to grow barley and keep dairy cattle in Greenland, neither of which should have been possible if one accepts the proxies uncritically.

Michael in Dublin
Reply to  Andy May
July 19, 2022 12:51 pm

Historical records are the best way to judge ancient climates. 

Two centuries ago a Scottish gardener moved to a semi-desert area in the center of Southern Africa to do mission work. He left a trove of journals including records of temperatures, floods, droughts and more. Those who keep predicting that things are getting hotter and drier in this area are blissfully unaware of the journals and that they simply confirm the recurring weather patterns.

We should preserve records of farmers from earlier centuries because they can give us valuable insights into the climate of their areas. Some were meticulous in their weather records recognizing the patterns helped them with their farming.

Reply to  Michael in Dublin
July 19, 2022 3:08 pm

People in Europe who suffered with the cold climate in the 1690s would have loved the climate we have had over the past 10 years.

But what would they know?
Complaining about the cold and famines in 1690’s Europe.
They were not climate scientists.
They had no supercomputers.
No climate computer models.

Just first-hand experience with a cold decade
— the coldest decade of the Maunder Minimum period.

Michael in Dublin
Reply to  Richard Greene
July 20, 2022 3:17 am

When millions of Africans pour into Europe, I think in some ways they are crazy. They have a huge continent with incredible resources and climates that are so much better than most European countries bar those around the Mediterranean. If there were no freebies in the EU and they had to work hard to support themselves and families, providing for their own housing, food, energy, etc – even if it meant hard physical labor – most would go elsewhere.

They need to work to fix up the mess in their home countries – dealing with civil strife, corruption, incompetent leadership and the likes. There is no good reason their countries should not be able to provide them with more comfortable lives than EU countries. The countries are certainly hotter but properly utilizing the ample rainfall in many areas they should be better able to adapt to and benefit from their climates – without all this climate alarmism.

Reply to  Michael in Dublin
July 20, 2022 2:10 pm

A layabout in northern climes used to have little chance of survival over winter. Thus, temperate regions became successful, as the weak were weeded out. The welfare state is changing this and as it attracts more and more layabouts from wherever, disaster looms.

Ron Long
July 19, 2022 10:35 am

The smarmy Alphabet People on CNN just told me that Europe and Texas are on fire and we are going to burn in a Living Hell on Earth, and it’s too late, but we should change to Undependables anyway, and Trump belongs in prison, and Brandon is OK. Who to believe?

Reply to  Ron Long
July 19, 2022 11:09 am

I know it is good to “know your enemy”, but why would you damage your psyche by watching CNN?

Ron Long
Reply to  Drake
July 19, 2022 1:29 pm

Because I lie in Mendoza, Argentina, and, for English, it’s either CNN or BBC. Sometimes I switch back and forth rapidly to see if they are really synchronized.

Reply to  Ron Long
July 19, 2022 2:26 pm

I had that experience on a cruise ship out of Vancouver, Canada about four years ago. I got one of the worst flu’s of my life as did a majority of the other passengers and my husband. All they had on tv was the BBC. I thought I’d lose my mind and if other passengers could hear me yelling at the tv, they probably thought I was out of my mind, too.

Reply to  KcTaz
July 20, 2022 2:12 pm

Millions of Canadians have, over the years, actually lost their minds from watching far too much CBC, and/or CTV.

alastair gray
Reply to  Ron Long
July 19, 2022 3:01 pm

The Long and the short of it is —-You and you do but how to get the mindless clods to form their own opinions? Right or wrong it would all come out in the wash.

Craig from Oz
Reply to  Ron Long
July 19, 2022 8:18 pm

Hot is 40C plus.

Starts to get a bit annoying, but is still livable. Wouldn’t run around in that sort of weather, but then again I try and avoid running at the best of times. Worse bit is that mild stinging in the eyes when outside as the heat dries the moisture out of them.

37C? That is just ‘use the shade and keep an eye on your water intake’.

Reply to  Craig from Oz
July 20, 2022 2:35 am

37C with 50% humidity is much much worse than 40C with 5% humidity.
Basically with temperatures over 37C and 100% humidity you are losing your ability to regulate your body temperature and you overheats.

Reply to  Peter
July 20, 2022 6:40 am

That is why the “heat index” was invented. To make us feel bad about the weather. Like the “wind chill factor” in winter. Atmospheric Gases dissipate heat not creat it. Hair dryers, car radiators, base board home heaters, etc.

Notice there is no “CO2 index” that tells you you feel warmer. CO2 can’t do what they claim.

AGW is Not Science
Reply to  Peter
July 23, 2022 10:27 am

Then, of course, that’s near physically impossible. Humidity is relative to temperature and declines as temperature rises. High dew points are a better indication of how miserably sticky things are, and to be sure the combination of high temperatures and high dew points are when you run the highest risk of becoming overheated.

Rud Istvan
July 19, 2022 10:48 am

The arbitrary 2C got changed by IPCC to 1.5C AFTER the energy budget observational ECS came in circa 2014-2016 about 1.7C, meaning we would never reach 2C anyway. Only way IPCC could pretend continued alarm.

Reply to  Rud Istvan
July 19, 2022 2:07 pm

To the dismay of children growing up being indoctrinated to think the world is going to end if we continue to use fossil fuels. It’s just evil.

July 19, 2022 11:51 am

Well done Andy May.

Ben Vorlich
July 19, 2022 11:57 am

There were frost fairs in London in 1715–16, 1739–40, and 1789. Only one more after that.

The worst storm ever recorded in the UK struck in the 18th century, damaging property, felling trees and killing thousands. The “Great Storm” hit southern Britain on the night of November 26 1703 and more than 400 windmills were broken.

1750 is a good place to start to show a warming climate, in the UK anyway.

alastair gray
Reply to  Ben Vorlich
July 19, 2022 3:02 pm

In teh preent day I would call 400 destroyed wind turbines a Good Start

Matt G
Reply to  Ben Vorlich
July 19, 2022 3:48 pm

It was known as ‘The Channel storm’ and killed 8000 people.

Tom Abbott
July 19, 2022 11:59 am

From the article: “Currently Schellnhuber admits that keeping global warming below two degrees is not feasible.”

That’s funny for a number of reasons. Schellnhuber thinks the more CO2 in the atmosphere, the more warm it gets. Not necessarily so. More CO2 is going into the atmosphere now, yet the temperatures are cooling.

What’s not feasible is reducing CO2 output. And there’s no evidence that temperatures would be different if we could reduce CO2 output.

Schellnhuber is assuming too much. Alarmist climate scientists do this a lot.

Reply to  Tom Abbott
July 19, 2022 12:18 pm

Why would anyone want to reduce CO2, especially since the WEF sociopaths and their stooges in government are doing all that they can to destroy the food supply?

If we aren’t allowed to have fertilizers, and they want to flush all the available fresh water into the sea, wouldn’t it make sense to increase CO2 so the plants have at least a chance of producing a sustaining harvest?

Or are we all now resigned to the fact that we have an obligation to die for the sake of the vanity of the Malthusians?

Reply to  Tom Abbott
July 19, 2022 1:08 pm

I told him (Schellnhuber) repeatedly and distinctly that the correct numbah is 1.9735 – not 2. And, we are perfectly OK at 1.9735.

David Dibbell
July 19, 2022 12:08 pm

I propose we describe all the worry over 2C warming and the like as a condition: Climate Dysphoria.

Reply to  David Dibbell
July 19, 2022 2:31 pm

This is still one of my favorite quotes ever from WUWT comments.

“I prefer to play on “clinically insane” with “climactically insane”

Pat from kerbob

July 19, 2022 12:16 pm

If governments are concerned about a 1.5 degree increase in global average temperature at some future date, then they should also be concerned about a 1.5 degree average decrease in global average temperature at some future date. Of course, you hear nothing about this at all, but it is a coming reality due to orbital mechanics and the end of the Holocene interglacial.

There is no planning at all to fight global cooling. This is a severe and dangerous oversight on part of all nations as glaciations are known to last 90,000 years. At what point do we stop limiting CO2 emissions and start adding CO2 emissions?

Peter Wells
Reply to  Doonman
July 19, 2022 12:21 pm

Absolutely valid observations on your part. This whole global warming business is a bunch of typical pseudo-scientific liberal verbal garbage.

Reply to  Doonman
July 19, 2022 2:36 pm

“this is a severe and dangerous oversight…”
It’s no oversight, it’s by design and it violates the Creed of CAGW

Thou shalt not speak of Global Cooling Past or Future.

Tom Abbott
Reply to  KcTaz
July 20, 2022 5:08 am

Yes, the Human-caused Global Cooling hysteria was a blackeye for alarmist climate scientists, and they don’t want to talk about it. They want us to forget about it. They want to erase it from history. It makes them look bad today because they are following the same unscientific path they took with global cooling, claiming they had evidence when they had no evidence.

It was Human-caused Global Cooling while the temperatures cooled, and then when the temperatures started to warm up after a few decades of cooling, then the alarmists declared it was Human-caused Global Warming. Alarmists are alarmed no matter which way the wind blows.

Michael in Dublin
July 19, 2022 12:44 pm

Thanks Andy.

Perhaps we should insist that those who spout the 2 degree limit explain scientifically where this comes from – and not merely refer to so ‘n so who is a scientist who said so. They must show us the science. If they cannot, there is no good reason to accept anything they are ranting about. Science is not speculation nor computer models but based on empirical observations and tested by experiments. I believe is it possible to experiment on the consequences of both increased temperatures and CO2 concentrations that prove their benefits not dangers.

July 19, 2022 12:46 pm

“forced union with England”

So Darien was somebody else’s fault?

July 19, 2022 1:06 pm

It was warmer than this made up 2C limit during all 5 of the warm periods during the last 6 years, plus all of the Holocene Optimum, and yet none of the bad things that these guys preach about happened.

Reply to  MarkW
July 19, 2022 4:03 pm

That was supposed to be 6000 years.

July 19, 2022 1:14 pm

‘A wake-up call’: as extreme heat hits UK, experts say net zero is the only way out

As UK reaches 40C and fires blaze, scientists warn of such temperatures every three years if emissions are not lowered

From The Guardian today. Notice that they just talk about ’emissions’, but when you hear supposed experts, they elide gracefully into talking about the UK Net Zero policies as if they would lower the relevant emissions.

Which of course they will not, their effects will be too small to be noticeable.

In the UK they have had about three days of unusually high temperatures – the kind of thing that happens once in every 30-40 years. But nothing very much over previous episodes.

The result has been the kind of media hysteria of the level seen after the death of Diana Princess of Wales. Read and repeated by the same people who go to Spain or Greece or further south every summer in quest of exactly these same temperatures.

I heard an amusing anecdote about it. A friend and wife were sitting out in the garden, and one of them refused to believe that the temperature was what the thermometer showed, because that, she had been assured, was a level of extreme danger, whereas they were just comfortably warm in the shade, drinking their tea.

No, it could not possibly be as hot as the thermometer was showing, or they would be in the late stages of heat exhaustion…

July 19, 2022 1:16 pm

Ever since the Earth acquired an atmosphere capable of supporting life as we know it (i.e., oxygen breathing animals and CO2-consuming/O2 emitting green plants), it has never been “dangerously hot” for plants and animals, since none of them existed until those very warm conditions became a thing hundreds of millions of years ago.

Certainly individual plant and animal species adapt themselves to warmer or colder conditions as they may, and wetter or drier conditions, and sunnier or cloudier conditions, etc. etc. But there is no indication that life as we know it not only tolerates far warmer temperatures than now but absolutely thrived in such warm temperature.

We humans, of course, have tolerated all manner of temperatures by adapting to the warms and colds of the Holocene and (our ancestors) the Pleistocene. After all, humans and our ancestors evolved throughout the entire Pleistocene, with its 26 major glaciation/interglacial cycles over the past 2.6 million years. If we are a result of such drastic climate changes, both warm and cold, then obviously WE are extremely adaptable to wide variations in climate.

July 19, 2022 1:45 pm

The 2ºC limit is a moving target, as the temperature datasets can be adjusted to show whatever they want. From HadCRUT 3 to 5, 0.2ºC were introduced in the period 1997-2014. This was done from exactly the same data.

If they want the limit to get closer or farther, they can do it easily. Just a new dataset release.

Reply to  Javier
July 19, 2022 2:48 pm

This HADCrut?

HadCrut4 Global Temperature, 1850 – 2018.
Absurdity everywhere in Hadley Met Centre data
Scandal: First ever audit of global temperature data finds freezing tropical islands, boiling towns, boats on land

DATA-Climate Bombshell: Global Warming Scare Is Based on ‘Careless and Amateur’ Data, Finds Audit

…The Hadley Centre and Met Office will find it difficult to dismiss McLean as a crank. In March 2016, he advised them of certain errors which they promptly corrected. So he’s an authority they take seriously.

James Delingpole7 Oct 2018

Changing temperature anomaly baselines
Posted on February 27, 2019 by Clive Best

← A comparison of CMIP5 Climate Models with HadCRUT4.6
2018 Temperature Comparisons →

Zeke’s Wonder Plot
Posted on January 25, 2019 by Clive Best
Zeke Hausfather who works for Carbon Brief and Berkeley Earth has produced a plot which shows almost perfect agreement between CMIP5 model projections and global temperature data. This is based on RCP4.5 models and a baseline of 1981-2010. First here is his original plot.
Again the models mostly lie above the data after 1999.
This post is intended to demonstrate just how careful you must be when interpreting plots that seemingly demonstrate either full agreement of climate models with data, or else total disagreement.
In summary, Zeke Hausfather writing for Carbon Brief 1) used a clever choice of baseline, 2) of RCP for blended models and 3) by using a 12 month running average, was able to show an almost perfect agreement between data and models. His plot is 100% correct. However exactly the same data plotted with a different baseline and using annual values (exactly like those in the models), instead of 12 monthly running averages shows instead that the models are still lying consistently above the data. I know which one I think best represents reality.

July 19, 2022 2:04 pm

”…in Nature, David Victor and Charles Kennel tell us that there is little scientific basis for the 2°C figure,…”

Yet the catastrophists are telling kids the world is going to end if it does. Which I find disgusting.

Chris Hanley
July 19, 2022 2:31 pm

… temperatures in the Arctic are rising much more quickly than in the rest of the world, including the Antarctic …

Figure 5 (GISTEMPv4) and the link to the AGU website refer to the Arctic warming in the satellite era, a period that for instance does not capture the effects of the AMO on Arctic Ocean temperatures, the surface record back to 1920 (HadCRUT4) indicates that the warming 1979 – 2022 is ‘cherry-picked’ i.e. unrepresentative of the complete observational record.

July 19, 2022 2:46 pm

The +2.0 and +1.5 degree “limits” are numbers pulled out of a hat or from two feet below the back of the hat.

We have no accurate real time measurements of the global average temperature in 1850. The rough estimates could be +/- 0.5 degrees C.
Barely any pre-1900 data from the Southern Hemisphere and ocean measurement methodology was mainly done in Northern Hemisphere sea lanes with questionable accuracy buckets and thermometers.

Ignoring the fact that 1850 measurements are close to wild guesses, what would happen if we trust the 1850 numbers and reach +1.5 degrees C. ?

Nothing would happen — people would not even notice.

The global average temperature has ALREADY reached nearly +1.5 degrees over “pre-industrial” in April 1998 and February 2016 — the warmest months during periods with very strong El Nino heat releases from the Pacific Ocean. While the El Ninos are temporary, and not caused bu greenhouse gases, we were close enough to +1.5 degrees C. to find out if the world would end.
It didn’t end from nearly +1.5 degrees C.

Reply to  Richard Greene
July 19, 2022 3:02 pm

I should add what I remember
from my college days
when getting a BS degree.
Real science:
Round numbers like +2.0 are
BS, baloney, malarkey and
banana earl (for those in Brooklyn).

Everyone knows at least three decimal places
are required for real science.

If they had claimed +1.543 degrees C.
or +2.382 degrees C,.
instead of +1.5 degrees C.
and +2.0 degrees C.
that would be real science.

I would take those numbers seriously.
I would sell my home in Michigan
and move to Alaska to escape the heat.
Or buy a better air conditioner.

Reply to  Richard Greene
July 20, 2022 6:11 am

No need to go all the way to Alaska, the UP is a lot closer….

alastair gray
July 19, 2022 2:55 pm

Mostly I agree with you vis a vis the Little ice age . Seen the evidence in Chamonix for the seventeenth century glacial maximum and retreat right up to the present day.
However you must be familiar with the Central England Temperature record

which I have no doubt is an honest attempt to present over 3 centuries worth of painstaking temperature recording. I don’t see the evidence for a brutal little ice age but yet I do not dispute the many historical accounts of dire weather . I remember the winter of 1963 Brutal and cold but not frost fairs on the Thames. The brilliant summer of 1976 in England did not stand out as a significant outlier from previous centuries.
. Can you attempt a reconciliation between two possibly conflicting sets of data

Matt G
Reply to  Andy May
July 20, 2022 11:06 am

The CET shows that the climate has become less extreme.

July 19, 2022 3:12 pm

AGAIN Dr Rosling has used the best data over the last 200 years and today we have increasing HEALTH and WEALTH,even though we’ve added another 6 billion people since 1920.
Watch his BBC 5 minute video and start to WAKE UP. And he has used 120,000 data points to support his claims.
You can BELIEVE the religious fanatics or start to THINK for yourselves.

Tim Gorman
July 19, 2022 3:16 pm

Currently temperatures are rising much more quickly in the winter and at night.”

This is why the 2C increase in the average is such a fraud! The average global temp can go up because of warming in the winter and at night. Max temps don’t have to go up at all!

And yet every single claim of harm to the planet assumes that the max temps are going up and that it will so negatively affect global food supply and sea level that it is a existential threat to mankind.

As Freeman Dyson pointed out years ago, the climate models are garbage – they are not holistic and do not tell us anything about the biosphere itself. The climate models themselves don’t tell us if an increase in the average global temp is a threat to humans or a boon to humans.

That means that the projections of future harm is an ASSUMPTION by those with an agenda to push. Critical thinking *should* lead each of us to question why that assumption is being made with no actual proof.

Bobby K
July 19, 2022 5:36 pm

Hi, came across some articles today. the articles themselves and all the comments below from all the people who agree with the articles and have their own agreeing opinions scare the living crap out of me. I’m really really trying not to lose it and avoid jumping off a bridge or something so I was hoping I could post them here and hopefully get a good debunking explanation for all of this. I know this may sound like an absolutely ridiculous request but I am seriously at the end of my rope here and desperately trying to hang on for my wife and daughter so if anyone could please help, I’m seriously begging, please.

Luke B
Reply to  Bobby K
July 20, 2022 12:58 am

You talk about needing refutations of more alarmist claims, but you should start by understanding what the scientific method is and isn’t. You appear to create problems for yourself by caring too much how many people think something, not enough why one would think it. A sense of what could not be true is useful for keeping balance.

For example, “positive feedback loops”: try building a system containing one that does not manage to self-destruct ($15 component goes up in smoke, literally — oops). As a general rule, I find that those on this site with any training or practice in control theory have the lowest tolerance for the idea that there are massive positive feedbacks quietly waiting to strike once some threshold is passed. I think that the reason for such scepticism is something like this: a system that changes irreversibly when we bump it slightly from its equilibrium would have done it in the past when ‘bumped’ by basically anything else whatsoever. The heuristic approach to the world that this group of people teaches us, as far as I can tell, entails a world close enough
to brink of disaster that such disaster should have happened long ago.

Regarding things being record-breaking and so forth. I’m aware that when one’s region seems to be getting hotter and drying out, it makes propaganda (I know that my university peers would consider it a strong assertion, but propaganda is clearly what it is) easier to take seriously. Thing is, that when encountering wetter weather, and a nearby area (strategically built on a historical floodplain) floods instead, that is said to constitute climate change also. Then at some point the though crosses my mind: isn’t a snow storm on my birthday for the first time in 25 years technically breaking a record also?

I would also add that it is at least somewhat dishonest to claim a record based on tenths of a degree when traditional measurements would have had to be interpolated. Additionally, a record is broken each time high temperatures
are reached in a slightly different location at a slightly different date, so this pretty much guarantees the existence of a bunch of record-breaking events perfectly ripe for cherry-picking later.

Bobby K
Reply to  Andy May
July 20, 2022 5:53 pm

Ok but can you explain how you know it’s not real science? I’m not arguing, I’m just trying to understand. There’s so many people saying that we’re doomed, that this is the end, that we’ve gone past any point of return and there’s now nothing we can do. They go on about the accelarating rate that the heat and melt is happening. How the arctic is heating up warmer than anywhere in the world, they go on about how much Greenland is melting and the amount of water going into the ocean. deforestation, major droughts, extreme heatwaves like the ones going on right now, that the warming is happening much much faster than the models could have predicted, that the scientists are downplaying it and not revealing how bad things really are, they say this is going to cause the collapse of civilazation, massive food and water shortages, mass migrations, human extinction, they say all of this IS happening, some are arguing within a couple of years and a lot of people are agreeing with that and defending that it is true, they say that the deniers and skeptics don’t understand the science and make their arguments without providing facts. I don’want any of this to be true, I don’t want to keep feeling like I’ve brought my almost 8 month old daughter into a doomed world where she has no future or at least a very dark and bleak one so please I’m asking, not because of previous predictions that didn’t come true, not just because of doomsday predictions being made for thousands of years but I’m asking currently, in the present, with everything that people are saying is going on and is happening, how do you know that none of them are correct. Not because of the past but because of the present, with science, how do you know that you’re correct and that they’re wrong? I’m not doubting or arguing, I’m just trying to understand. I’m not trying to come off as alarmist, I’m just terrified and hoping to find that none of this is as bad as they’re making it sound, so please if you have it in you at all to help out a total stranger who is seriously about to lose it, please I am begging for help. Please explain how in science you know that they’re wrong

Tim Gorman
Reply to  Bobby K
July 21, 2022 11:22 am

Freeman Dyson said a number of years ago that the climate models are not adequate, they are simply not a holistic look at the Earth’s biosphere. You simply cannot make valid judgements if you don’t have a complete picture. Focusing on something like a global average temp (which doesn’t actually exist) is a lot like a group of blind people trying to describe an elephant based on feel alone. Each focuses on just one piece of the animal and misses the whole.

Think of the GAT this way. Winter temps have a wider variance than does summer temps. When they form daily averages from temps in the northern hemisphere with daily temps in the southern hemisphere this results in jamming data sets with different variances and standard deviations together. That doesn’t result in a very good picture of what is going on. Then when they average all those daily averages together to form global monthly averages, they wind up jamming cold temps in one hemisphere with warm temps in the other hemisphere. That results in at least a bi-modal distribution and the use of the typical statistical descriptions of average and standard deviation gives a false picture of the data, the data should be described using what is called the 5-number description, minimum, first quartile, median, third quartile, and maximum.

If the climate models would output 5-number descriptions of future climate conditions we would be much better able to judge what is going on with the global temperatures. Knowing minimum values, maximum values, the median value, and the quartiles would probably not lend themselves to climate alarmism however. And we would *still* only have a partial picture of the entire biosphere.

July 19, 2022 10:37 pm

What is your Datum in figure 3, the average (mean) of each latitude. It’s interesting that the NH trend is an outlier. Is there a “shale-equivalent” baseline you would use for all the time series? Normalization on the LIA really pops out the NH.

July 20, 2022 12:11 am

Andy, fantastic paper, I am not a scientist, but extremely sceptical on the incessant climate alarmism. I have read and understood, your paper, why is this great work not being shoved up every politicians backsides, so that there can be some sensible debates, rather than non stop drivel. Suspect I know the answer. Keep up the good work all of you on WUWT, you are keeping me sane.

July 20, 2022 7:51 am

You may want to compare the above heat map with this one..

comment image

Gordon A. Dressler
Reply to  E. Schaffer
July 20, 2022 11:56 am

OK, I duly did so.

I failed to see any correlation of north polar warming to flights over that region. Nor any correlation of the “hot spot” warming in Antarctica at about the same longitude as South Africa to any airplane flights to or over that region.

Now what?

Gordon A. Dressler
July 20, 2022 9:17 am

“Oh puny little men, thou darest to think thou hast dominion over me . . . how’s about I bring on yet another 50,000 year glacial interval so thou canst showeth me how thou doth prevent climate change?”
— Mother Nature

Reply to  Gordon A. Dressler
July 20, 2022 10:37 am

Make that 70,000 years. That is how long the next interglacial will last, as determined by orbital changes. That is 35 times the span since the Roman Empire heyday, or 7 times the span of the entire human civilization since the invention of agriculture.

Oh, have we been lucky to be born in an interglacial! For the best, hilarious view of human life at the end of the Pleistocene you should read “The Evolution Man” by Roy Lewis.
A book first published in 1960 (as What We Did to Father) that I read in the late 1970s (then published as Once Upon an Ice Age). Humankind is going to need humor and guidance to go back to the Pleistocene.

Matt G
July 20, 2022 12:10 pm

The Severn Estuary flood on 20 January 1606 killed 2000 people caused by high tides and violent storm.
In Lewes, East Sussex snowdrifts caused an avalanche and killed 8 people on 27 December 1836.

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