There’s an assumption out there that if you “accept” the science of climate change, you are obliged to support drastic measures to cut greenhouse gas (GHG) emissions.
This is not true.
The one does not follow from the other. Mainstream science and economics do not support much of the current climate policy agenda and certainly not the radical extremes demanded by activist groups.
In a recent peer-reviewed paper, my co-authors and I proved this using one of the economic models that governments and academics around the world rely on.
Policymakers compute the social costs of GHG emissions using tools called “integrated assessment models” (IAMs), which contain linked climate and economic models.
They run the world forward in time for a few hundred years and estimate the value of damages from a tonne of GHGs emitted today.
Pardon all the acronyms but that’s called the “social cost of carbon,” or SCC, and it represents an upper bound on what we should pay per tonne to cut emissions.
The higher the SCC, the more aggressive climate policy should be.
During the Obama years, the U.S. Environmental Protection Agency (EPA) convened an expert group to use the three best-known IAMs to estimate the SCC from now to the middle of this century to guide regulatory rule-making.
Most of their results were in the US$20 to US$60 per tonne range, depending on the discount rate (which controls how much weight to put on far-future damages).
The benefit of climate policy is to get rid of this future damage. If the damage is US$60 per tonne, then policies costing more than $60 per tonne of reduction don’t make sense. You wouldn’t spend more than a dollar to save a dollar.
Like all models, IAMs depend on key parameters that are drawn from the scientific literature. It has long been known that although CO2 is a greenhouse gas, it’s also food for plants. So extra CO2 in the air benefits plant growth.
Yet two of the EPA’s three IAMs assumed that boosting the carbon dioxide content of the air has no effect on agriculture, which is overly pessimistic.
Only one of the models allows for a small gain in agricultural productivity as CO2 levels rise, based on estimates from the 1990s of the size of the effect. So that’s the one we used.
However, we first updated the IAM to take account of the extensive research since the 1990s looking at effects on global plant growth from rising CO2 levels.
Results from satellite-based surveys and field experiments have shown larger benefits than people predicted in the 1990s, even in a warming climate, especially for the rice crop in Asia.
Also, all the IAMs assume the climate will warm by three degrees Celsius with every CO2 doubling.
This is based on simulations with large climate models, but there have been many recent studies in climate journals estimating lower sensitivity based on the observed ground- and satellite-measured temperature changes.
So we incorporated this information into the IAM as well.
Based on these updates alone, we showed that even using a low discount rate, the social cost of carbon as of 2020 drops from US$32 per tonne to about 60 cents, and there’s a 50/50 chance it’s below zero.
It does grow over time but not by much. By 2050 it’s still under $3 per tonne and has a 46 percent chance of being less than zero.
Note that we did not say “climate change is a hoax so we shouldn’t do anything.”
We relied on scientific studies in mainstream journals, combined with one of the Obama-era EPA’s own preferred economic models, to determine if costly climate policies are justified.
The answer is no, at least not for the next few decades.
Our paper was reviewed by three knowledgeable anonymous experts who were surprised by our findings and aggressively challenged them, with one strongly recommending our study be rejected.
We had to rebut their extensive counterarguments in detail. We were able to defend our calculations and the journal decided in our favor.
If you don’t believe the science of climate change, then you obviously won’t support carbon taxes and other such policies.
But it’s important to note that if you do accept the science, you aren’t obliged to support every policy, no matter how costly or inconvenient, that gets put forward. We should still focus on no-regrets strategies where the benefits outweigh the costs.
Ross McKitrick is a professor of economics at the University of Guelph and a senior fellow at the Fraser Institute.
Read more at Financial Post
The ignorant sheeple demand impoverishment with social monitoring, and they wish to foist it on all the rest of us.
Congratulations on getting such a study published.
Ross..
I have a question for you…
The UN IPCC says that a doubling of CO2 from 400ppm to 800ppm would result in a global temperature increase of about 2C degrees. OK?
The increase is 400ppm. That is 1 part in 2500.
Therefore the IPCC is saying that 1 molecule of CO2 can “trap” enough “heat” to raise the temperature of the other 2499 molecules of Nitrogen [N2] and Oxygen[O2] about 2C degrees.
That, to me, is absurd.
What do you say?
Here is my question:
If I have a picnic cooler of dry ice and I place my beverages in it, does the dry ice [CO2] “trap” the heat from the beverages, and back radiate it to make my drinks hotter?
Not at my picnics has it ever happened.
BTW, that dry ice is about 100% CO2 not 0.04% as is in the atmosphere.
The Subject of Deep Ecology soon they will be sacrificing Virgins and Children to their Nature Gods when the sun gose sets or rises the Sunrise Movement sounds like group of loose nuts to avoid
The goals driving the climate change movement are the radical agendas. As such, it is just as useless to them to have carbon dioxide priced at 60 cents a ton as it is to be admit that carbon dioxide has no impact on the climate. That explains why this article was so strongly opposed.
The real issue here is the assumed causal link between emissions and all of these impacts such that the impacts can be moderated simply by cutting emissions.
https://tambonthongchai.com/2019/11/16/agw-issues/
https://tambonthongchai.com/2019/11/08/remainingcarbonbudget/
It is very clear from all the climatology energy diagrams showing back radiation that climatologists (and thus all the computer models) assume that the surface is warmer than the direct solar radiation could make it because of the back radiation supposedly causing about twice as much heat into the surface (324W/m^2) as the solar radiation (168W/m^2) supplies.
You all need to face the FACT that climatologists QUANTIFY the surface temperature by adding together the fluxes from the Sun and the atmosphere, then deducting the cooling flux by evaporation and conduction-cum-convection out of the surface, and then using the net total of about 390W/m^2 in Stefan Boltzmann calculations that then give 288K for a uniform flux day and night all over the globe (LOL). The fact that it is variable would give a mean temperature at least 10 degrees cooler – like about 5C.
This is totally wrong. Nothing in established physics says you can add fluxes like that and get correct results in Stefan-Boltzmann calculations. Nothing in established physics says the solar radiation can make the surface hotter than the black body temperature for the mean flux. There is no experiment that confirms radiation can be added this way – nothing anywhere! A simple experiment comparing the warming effect of a single artificial source of radiation and the warming by multiple such sources PROVES that this addition of radiative fluxes does NOT give correct results in Stefan-Boltzmann calculations, yet the WHOLE radiative forcing climate change conjecture is BASED on that FALSE assumption.
And THAT is the reason Roy Spencer’s graphs show no warming since the peak in the 60-year cycle back in 1998 and will not show future warming until after 2028. There may be more then, but the long term cycle of about 1,000 years should turn to cooling perhaps before any more than another half degree of warming after 2028. Cosmic rays vary for several reasons and they are now shown to affect the amount of cloud cover, and thus cause natural climate cycles.
Lets hear from the Experts and not from some loose nutcase who gets their message beamed to them by a giant invisible chicken