Contributed by Robert Lyman 2020. Lyman’s bio can be read here.
In my recent commentary and PowerPoint presentation on the economic and financial costs that climate policy has imposed on Canadians, I showed that the tab already runs to hundreds of billions of dollars. See that report here:

The cost to date, of course, is just the beginning. The continuation of present policies and of others to reduce the production and consumption of fossil-fuel-based energy services may increase those costs into the trillions of dollars. The natural question to ask is what benefit Canadians can expect to derive from incurring the present and future costs of emissions reduction.
There is no simple answer, but I will offer an abbreviated one, and encourage readers to find out more.
Canada’s current climate policy target is to reduce greenhouse gas emissions by 30% from 2005 levels by 2030; in slightly more understandable terms, that means reducing emissions from 716 megatonnes (Mt) per year of carbon dioxide equivalent in 2017 to 511 Mt in 2030. That is the voluntary target set by the federal government in 2015 and included in the plan that Canada submitted to the United Nations following the 2015 Paris Agreement. The Trudeau government, not waiting to see whether attaining the 2030 target is feasible, has already announced that it wishes to reduce emissions to “net zero” (largely unexplained) by 2050, thirty years from now.

Let us examine what the benefits would be, in terms of global temperature reductions, if Canada were to achieve the 2030 target.
Some Necessary Science
According to generally accepted (but highly questioned) theory, the effect of carbon dioxide emissions on global climate is felt through the increases in global concentrations of CO2 in the atmosphere. To quote Professor Ross McKitrick:
“The global carbon cycle is vast and slow, so a change in local emissions today will have only a small global effect, and only after a very long time lag. About 20 years after a pulse (release) of CO2 emissions to the atmosphere, only about 40 per cent (plus or minus 15 per cent) of the emitted molecules will have been sequestered. After a thousand years about 75 per cent (plus or minus 10%) will have been sequestered, and the remainder will be removed over the ensuing tens of thousands of years. Likewise, emission reductions take decades or centuries to lead to a reduction in the global concentration.”
McKitrick, Ross. A Practical Guide to the Economics of Carbon Pricing. University of Calgary School of Public Policy, September 2016
Economic Models
To measure the effect of emissions reductions on global temperatures, the U.S. Environmental Protection Agency funded the development of the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) model. A key parameter of the model is the expected climate sensitivity to a doubling of CO2 concentrations, which ranges typically from 1.5 degrees Celsius to 4.5 degrees C.
Using the MAGICC model, Bjorn Lomborg, Professor at Aarhus University in Denmark, estimated what the effect would be if all the countries party to the United Nations Paris Agreement honoured their commitments to emissions reduction in the period to 2030 and further continued those measures in place for an additional 70 years, to 2100.
The result would be a temperature reduction from any of the IPCC’s scenarios of somewhere between 0.05 degrees C. and 0.17 degrees C. In other words, if all the countries complied, the resulting global temperature increase would be, at best, less than one fifth of a degree in the year 2100.

Wait, there’s more. That does not mean temperatures would cease increasing. The temperature decline resulting from the measures taken would be made up in the following ten years, by 2110. So, the warming would be deferred, not avoided.
According to estimates produced by the Stanford Energy Modelling Forum, the cost of the global measures would run to over one trillion U.S. dollars per year (i.e. at least $100 trillion by 2100). Almost all (98%) of the emissions reductions would come after 2030.
The Benefits to Canada
The Canadian government has not published estimates of the magnitude of emissions reductions it will achieve by 2100 or of the temperature-related effects. Ross McKitrick, however, estimated that a 30% reduction in base year emissions would, by 2100, eventually reduce the rate of increase in the global CO2 concentration by about 0.01 parts per million per year, orders of magnitude smaller than the monthly fluctuations in the global record.[ McKitrick, ibid, page 4 ] For all practical purposes, it would have no discernible global effect.
Somewhat surprisingly, that is the best case. It assumes that all the other countries of the world will be “doing their part” to reduce emissions. In fact, as is well documented by the British Petroleum Statistical Review of World Energy, global GHG emissions rose 12 per cent over the past decade, Further, only 17 of the 185 Parties to the Paris Agreement are on track even to meet their 2030 emission reduction commitments.
Every few years, industrialized countries like those in western Europe and Canada announce ever-more-stringent political targets for emissions reduction. Just as regularly, they fail to meet them. Only a few countries have incurred the high economic costs that Canada has in its resource sector.
There are many other complex factors to take into account if one wishes to understand the costs and benefits of emissions reductions in the period to 2100. Notably, recent empirical studies have indicated that the sensitivity of the global climate to increases in carbon dioxide concentrations may be far less than assumed by the Intergovernmental Panel on Climate Change (IPCC). Also, the beneficial effects of increased carbon dioxide concentrations on the growth of global forests and crops may be far higher than the IPCC has recently estimated.
However, we have a fairly clear estimate of the global emissions effects and temperature changes due to Canada’s environmental sacrifice – zero.

Bob – good job in explaining the cost (and lack of benefits). Lets hope the main stream media will pay attention.
This has certainly achieved a big reduction in comments – a pity but I wonder why. Has this article been published elsewhere to engender some feedback? I hope that no critical comments mean it can’t be faulted.
You forgot Rf]Richard Tol.