Some reasons for skepticism regarding “Climate change”
I presume that our shared goal is to enhance human flourishing. If you have a different concern then this list probably won’t be useful to you.
Climate is weather over a long period, usually considered 30 years or more.
All agree that climate changes over time. The globe has been both much warmer and much colder in the past.
“Climate change” is shorthand for the theory that mankind’s CO2 emissions cause the earth to warm over time, that this warming will be substantial, certainly more than any natural warming, and that it will be harmful on balance, perhaps catastrophically harmful.
“Adherents” is my term for those who believe and promote this theory. I use that rather than “alarmist”, which has a pejorative connotation.
“Skeptics” are those who believe that there is insufficient evidence to support this theory, or that the benefits of fossil fuels and CO2 itself overwhelm any potential ill effects. I use it rather than the term “denier”, which has a pejorative connotation.
Overall reason for skepticism
Adherents and climate activists have not provided evidence for their views. Most often, they refuse to even state a case. Rather, they declared decades ago that “The science is settled”, neither stating clearly just what that alleged settled science claims nor providing evidence and reasoning for the claim.
There are many possible explanations for the modest warming we have seen since emerging from the “Little Ice Age” around 1850. A skeptic need not champion any. His proper role is to assert that the proponents have not offered evidence for their case and to vigorously challenge them to do so.
66 (and counting) specific reasons for skepticism (in no particular order, for now)
Activists resort to name-calling, tarring their intellectual opponents as “climate deniers.”
What is this intended to mean? I know of no one, neither scientist nor layman, who denies that there is a climate, nor even that climate changes over time.
If the activists had a sound scientific case to make this name-calling would not be necessary,
Optimistic solar and wind projections are made by people who would oppose those things if they were actually buildable. - Alex Epstein
We are safer from climate than ever before. At least 50x safer in 2020 than in 1920, in large part due to fossil fuels.
Adherents play a shell game, conflating a consensus that we have warmed, which exists, with one that mankind is responsible for most of the warming, which does not exist.
The claim that “97% of scientists agree” is an example of the aforementioned shell game. Economist David Friedman explains its fallacy here:
The point of the petition is not that numbers create truth, but simply to rebut the claim by some adherents that scientists are nearly unanimous in support of their view.
Even if there were a consensus, that would signify nothing without a well-supported argument. We weigh evidence, not scientists.
In response to the 1931 book “100 Authors against Einstein”, the physicist replied “"Why one hundred? If I were wrong, one would have been enough."
Sea level has been rising roughly 7 inches per century for the past 2000 years, and the rate does not seem to be accelerating.
Per Dr. Art Robinson in 2021:
Sea level has been rising for 150 years at a linear rate of about 7 inches per century, with fluctuations between 0 and 12. These fluctuations correlate well with world-wide glacier shortening and the US temperature record.
From 1950 to the present, human carbon use increased more than 6-fold, yet the rise rate in sea level did not measurably increase. Carbon use had no effect on sea level.
There is no experimental evidence that verified the hypothesis of catastrophic flooding, with or without human activity.
From 1950 to the present (2021), there has been no upward or downward trend in the number of violent Atlantic hurricanes.
The number of violent hurricanes that made landfall has not increased.
The maximum wind speed of violent hurricanes has no increased.
The average number of US tornadoes has decreased.
- Dr. Art Robinson
The world has many more polar bears now than in 1970 or 2000.
Al Gore famously noted that historically (over millennia) CO2 was correlated with temperature. He failed to note that in the historical record rising temperature precedes rising CO2, so the latter could not cause the former.
Due to natural forces, the earth has been warming since the end of the little ice age, around 1800.
This is a good thing - cold is the great enemy of mankind. There is a reason people retire to Florida rather than Manitoba.
Land surface records can be unreliable, partly due to "massaging" of the data by the scientists entrusted with these records and partly due to the urban heat island effect, whereby once rural temperature stations become urban over time.
We see a much reduced warming trend if we consider only stations that have remained rural.
The Climatic Research Unit at the University of East Anglia famously discarded the original temperature data records that had been entrusted to them in favor of data that they had manipulated, in their eyes to correct errors.
The late scientist Dr. Fred Singer noted that late 20th century temperature records show warming in the land station records but that this warming does not appear in the satellite records available since 1978
Michael Mann's "hockey stick" graph was so thoroughly debunked in 2004 that even the IPCC stopped using it.
For a thorough treatment, see Andrew Montford’s “The Hockey Stick Illusion” (Montford 2010)
The Medieval and Roman warm periods were likely warmer than today.
Human civilization has tended to thrive during relatively warm periods.
Adherents usually ignore the enormous benefit of CO2 in and of itself, namely that it enhances agricultural productivity. Horticulturalists pump CO2 into their greenhouses to achieve concentrations above 1000 ppm. NASA tells us that the globe is 1/3 greener than it was in 1960, mainly due to increased atmospheric CO2.
Obama science advisor John Holdren predicted in the 1980s that we’d have up to 1 billion climate deaths today.
Most warming occurs in colder regions and at night.
We live in an inter-glacial period during an ice age. The glaciers will return again. No one knows when, but likely sometime in the next few thousand years. That is a threatvastly more dangerous than warming.
Solar and wind power are not practical replacements for fossil fuel and nuclear power for a few reasons.
The wind doesn't always blow and the sun doesn't always shine – we don't yet have practical means of large scale energy storage for those time when nature does not cooperate with is. Because of subsidies and mandates we have no way of knowing whether these things are truly price competitive. Powering the entire US this way, even if the storage issue could be solved, would require roughly 1/3 of our land mass. These plants seldom meet initial projections for output or longevity. Putting these on the grid requires fossil fuel backup, but since the backup does not run continuously it becomes less efficient.
“We get a tax credit if we build a lot of wind farms. That’s the only reason to build them.”--Warren Buffett.
Most adherents rely of predictions of climate models. These models have never been validated, that is, they have not been shown to make skillful predictions. In fact, they have been invalidated in that they all have predicted more warming than has actually occurred.
We learned from the Climategate leaks that adherent scientists have been actively preventing skeptical articles from being published. They then claim that the small number of skeptical articles is evidence that there are no skeptical scientists.
We also learned from Climategate leaks that scientists including Michael Mann were involved in an attempt to eliminate the medieval warm period, that is, to make a compelling case that it had never happened. This conflicts with the scientific method, where a scientist follows the data where it leads rather than attempting to bend it to his will.
Also from Climategate we know that computer models have a large number of tunable parameters and that by changing their values the modeler can achieve pretty much any result.
CO2's contribution is logarithmic - each molecule produces less warming than the previous one. Adherents seldom mention this.
Per the greenhouse gas theory, we would see a similar amount of warming when atmospheric CO2 increases from 300 PPM to 600 PPM as we would from 600 PPM to 1200 PPM.
Articles that mentions increased heat deaths in summer but fail to mention decreased cold deaths in winter are dishonest.
Per many studies, including a recent article in “The Lancet”, deaths from cooler winters strongly outnumber deaths from warmer summers.
Similarly, it is dishonest to to mention decreasing arctic ice cover without mentioning contemporaneous increases in antarctic ice cover.
Similarly, it is dishonest to mention retreating glaciers without also considering advancing glaciers.
Each IPCC report has been accompanied by a significant scandal.
These include, but are not limited to:
Ben Santer changing the text of the scientific report in AR3 after it had been approved, to bring it in will with the summary for policymakers.
Citations of “gray” literature.
Claims about the Himalayas.
Publication of the summary before publication of the scientific report on which it is based. This makes it appear as if the summary is politically motivated rather than drawing conclusions from the evidence gathered.
If climate change were truly an existential threat then adherents would favor expansion of nuclear power. Many or most do not. Some want to see nuclear powereliminated entirely.
Historically, nuclear is by far the safest form of power generation, safer than coal, gas, oil, hydro, solar, or wind, even when we take Chernobyl into account.
Politically, nuclear power’s detractors have the upper hand in the US. We have been decommissioning perfectly good nuclear plants and have not built a new one in over 40 years. (To do: check when the last one was put into service.)
Per Dr. Richard Lindzen's "3 Nutshells" paper, there are not two narratives but three. The first two groups tend to be measured in their claims, the third is strident and promotes alarm.
Climate scientists who believe that CO2 will cause substantial warming
Climate scientists skeptical of this claim
Media plus politicians.
Activists in the 1970s were concerned about global cooling. In the 1980s they switched their concern to global warming. In each case their proposed remedy was the same - deindustrialization and a massive transfer of wealth to the third world.
This doesn't tell us anything about the validity of the science but does give some insight into what motivates some activists.
UN officials have publicly stated that the threat of warming is reason to remake the global economy along authoritarian lines.
It is a principle of logic, thousands of years old, that a single line of reasoning is more convincing than multiple lines. Might that apply to this list? I hope not! I am not making a contention, but criticizing one. There are many ways the adherents’ arguments could be flawed, some of them mutually exclusive.
Usually people who point out flaws are called “whistleblowers”, but in climate science, they’re called “deniers”. If the crisis-team had evidence, they would provide it. Instead they call people names. Gore’s staffers were so outrageously viperous about one eminent physicist, Fred Singer, that he sued them for libel and won. - Per Joann DeNoiva
To get a truer sense of whether temperatures are increasing we should look at the number of record high and record low temperatures each year. These are measured locally and not subject to manipulation by central authorities.
There is indeed a rough consensus among climate scientists that doubling CO2 concentration (e.g. 300 to 600 or 500 to 1000 ppm) will tend to increase surface temperatures by about 1.1 degree C on average, before any feedback effects. Such feedback can be both positive (amplifying) and negative (dampening.) Whether the net effect is positive or negative and to what degree has been a field of active research for decades and there is as yet no consensus on that. The IPCC, though, proceeds on the assumption that net feedback will be strongly positive, and this assumption is built into all the climate models that the IPCC cites.
GCMs (General Circulation Models) cannot model clouds well. Clouds and cloud formation are too complex. So they ignore them. Yet clouds are crucial to climate.
GCMs are chaotic, that is, they have a strong dependence on initial conditions. The same model might produce results ranging from -1 degree C to +6 degrees. When this happens the modelers report the average of the various runs. Whatever this is, it does not seem like science.
The IPCC's essential argument is that "We don’t know what else could have caused that warming, so it must be CO2.” This is an example of the fallacy known as the argument from ignorance.
The commonly cited figure of 1.5 degrees of warming is measured not from the present day but from the "pre-industrial" period starting around 1850. This causes much confusion since we have already seen 1 degree C of warming yet we are safer from climate than ever before.
Fear of a "tipping point" is often cited as reason for alarm but there is no evidence that such a tipping point exists and much evidence that it does not. The earth has often had much higher CO2 levels in the past yet the planet did not experience runaway warming.
Some argue that reducing CO2 is simply taking out an insurance policy. This would be a strange policy indeed, where the cost of the premium is higher than the cost of the unlikely event one is insuring against.
Those who demonize fossil fuels invariably consider their costs but not their benefits. Conversely, when proposing alternatives they enthuse over benefits but overlook costs and drawbacks.
One alternative cause of warming is the role of cosmic rays on cloud formation, as discovered by Hans Svensmark.
Another alternative cause of warming is the sun. Per the recent paper by Soon et al, there are many estimates of solar irradiance over time and the IPCC uses the lowest. Depending on which data set one uses, one could conclude that the solar variability is responsible for 0% of the warming, 100% of the warming,or anything in between.
In the 20th century we saw decades of warming, followed by decades of cooling, followed by decades of warming. No one asserts that the first warming period was caused by CO2, but that leaves the explanation for it mysterious. Whatever caused the first warming period might well also have caused the second.
Remediation would be a reasonable alternative to prevention, for a few reasons.
First of all, prevention may be impossible.
Second, Remediation is much less expensive. Geoengineering proposals (e.g., as aerosol seeding) have been made that would cool the planet at low cost and that are temporary in nature, thus low in risk of unintended consequences.
Third, we might see substantial warming for reasons unrelated to CO2, and it would be useful to have a means of dealing with it if we find the result untenable.
Fourth, geoengineering could be applied only when a problem actually manifests, not when it is hypothesized.
No one can say what the optimum temperature of the globe should be.
The IPCC is a governmental organization. In other contexts we have learned to be wary of government pronouncements. An alternative organization, the NIPCC, reaches the conclusion that "Nature rules the climate."
Politicians naturally want to increase their own power. They went into politics to make a difference, and more power lets them make more of a difference.
An existential crisis provides reason to increase government power at the expense of individual rights. This does not tell us anything about the science, but should lead us to be wary of politicians who promote alarm.
Per H. L. Mencken, "The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary."
Science does not speak with one voice.
A relatively new field of “Prediction science” was founded by J. Scott Armstrong of the Wharton School. Those who predict climate catastrophe ignore many of its tenets.
The IPCC forecasts that "a no policy baseline would reduce (global) GDP 2.6% by 2100." They also note that in 2100 real global GDP will likely be roughly 400% of what it is today. Thus, the prediction is that, if the IPCC’s dire forecasts prove accurate, instead of 300% richer, we’d be only 297.4% richer than we are today.
Environmental activists have been predicting doom for decades and longer, going at least back to Malthus. This does not mean any particular claim must be groundless, but it gives us more reason to approach all such claims skeptically.
Recovered activist Michael Shellenberger, author of Apocalypse: Never, notes that the anti-fossil fuel movement has all the attributes of a religion.
“Global warming is the mother of all environmental scares. Warming (and warming alone) through its primary antidote of withdrawing carbon from production and consumption is capable of realizing the environmentalists' dream of an egalitarian society based on rejection of economic growth in favor of a smaller population, eating lower on the food chain, consuming a lot less and sharing a much lower level of resources much more equitably.” - The late Aaron Wildavsky, Professor of Political Science at U.C. Berkeley.
Related to my dad’s observation above, climate change is extremely convenient for politicians who want to rally the populace against some danger that is in the indefinite future. For a fictional presentation, see the excerpts from the play “Yes, Prime Minister” on my website:
Negative feedback tends to dominate in the systems we see in nature, since systems dominated by positive feedback are not stable.
“Although these relationships are varied, complex, and not yet well understood, that the climate has been stable suggests that the many processes act in concert to try to stabilize the climate rather than create large, nonlinear outcomes and runaway effects.”
⁃ Adherent climate scientist Charles MacCracken.
CO2 is not a pollutant, regardless of the EPA’s contention that it is. That is precisely the question under discussion. Remember that we all exhale it with every breath.
Human annual CO2 output is roughly 5% of total CO2 annual output. No one has a good handle on the earths “carbon budget”, that is, the total amount of sources and sinks.
Adherents assert that CO2 has an atmospheric half-life of hundreds of years. There is much evidence against this, but it is a cornerstone of GCM models.
Movement of carbon from the atmosphere to the oceans has a half-life of seven years, per Dr. Art Robinson
The earth could warm or cool substantially, as it has in the past, for reasons nothing to do with mankind. Should this occur we will need all our resources to deal with the change, and we will deeply regret impoverishing ourselves with fossil fuel restrictions.
Rich nations can, to a degree, afford to restrict fossil fuels. However, doing so would be a disaster in poorer counties, significantly shortening life expectancy and potentially leading to millions of deaths.
Energy poverty is a real problem in many countries, with people freezing to death even in relatively prosperous countries due to the inability to properly heat their homes in winter.
TODO: Need references. China, UK?
Many proponents believe they are engaged in a moral crusade. They then feel justified in downplaying fossil fuels’ benefits and overstating any drawbacks.
Were the US, the leading source of CO2 today, to somehow eliminate all CO2 emissions tomorrow, the effect on temperature in 2050, per the IPCC’s median estimate, would be 1/100th of one degree.
TODO: Need a reference and calculation for this.
NOAA applies adjustments to the global historical temperature data daily, and for no evident reason
“The Cooling World: ‘Climatologists are pessimistic that political leaders will take any positive action to compensate for the climatic change, or even to allay its effects.’”
In 1989, the AP reported that according to the UN Environmental Programme's Noel Brown: "entire nations could be wiped off the face of the Earth by rising sea levels if the global warming trend is not reversed by the year 2000"
"[By 1995]... somewhere between 75 and 85 percent of all the species of living animals will be extinct.”
~~Senator Gaylord Nelson, quoting Dr. S. Dillon Ripley, Look magazine, April 1970.
Paul Ehrlich, 1986: “As University of CA physicist John Holdren has said, it is possible that carbon-dioxide climate-induced famines could kill as many as a billion people before the year 2020.”
Starting 2013-2018 there will be no summer Arctic ice. - James Hansen, 2008
"Climate change over the next 20 years could result in a global catastrophe costing millions of lives in wars and natural disasters."
The Guardian, 2004
"The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now."
—Paul Ehrlich, the media’s leading environmental expert for 50+ years, 1968
New Ice Age Coming - Washington Post, July 9, 1971
"But the end of the Maldives... could come sooner if drinking water supplies dry up by 1992, as predicted."
—Canberra Times, 1988
Many predictions of “Peak Oil”.
“By the year 2000, if present trends continue, we will be using up crude oil at such a rate…that there won’t be any more crude oil.”
—Kenneth Watt, ecologist, 1970
"Global production of conventional oil will begin to decline sooner than most people think, probably within 10 years"
"Country Faces an Overpopulation by 1975, with Farms Unable to Feed All, Experts Say"
--The New York Times in 1952, fearing that US population would reach 190 million people.
"The ravenous American appetite for minerals will lead to severe shortages in the next few decades unless the nation stops wasting resources... increasing dependence on low grade ores also mean[s] increasing costs."
--The New York Times in 1973
"The Everglades National Park faces a decisive threat to its existence. On a site at the northern edge of the park, Miami proposes to build the world's biggest airport, covering 39 square miles."
The New York Times, 1969
"The Forests are Dying - Acid Rain over Germany" - Der Spiegel 1981
"The honeybees are dying — and we don’t really know why."