Exaggerated computer predictions of climate change promote overly-stringent and economically damaging government policies in Canada

By Kenneth P. Green. Kenneth P. Green is a Fraser Institute senior fellow. 

• Over the last two decades, Canadians have been subjected to ever-greater regulation and taxation in the name of combatting man-made climate change.
• The justification has been the claim that climate change is a severe threat to the well-being of Canadians as well as a rapidly growing global threat.
• This justification, in turn, is based on computerized models of the climate generated or relied upon by the United Nations Intergovernmental Panel on Climate Change (IPCC), the pre-eminent voice on the issue of manmade climate change since its founding in 1988. These models assume that Earth’s atmosphere is highly sensitive to, and easily warmed by, the addition of greenhouse gases from human activities such as energy use, manufacturing, agriculture, forestry, and essentially all industrial activities.
• While the IPCC’s estimate of climate sensitivity for a doubling of atmospheric CO2 levels over the near term is 1.8°C of warming, with a likely range of 1.4°C to 2.2°C, more empirically based estimates suggest that this Transient Climate Sensitivity is around 1.20°C, with a likely range of 1.1°C –1.65°C, and possibly lower.
• A review of similar disjunctions between high-sensitivity computer-model projections of “extreme weather” stemming from man-made climate change and empirical measures of change to date also suggest that high estimations of climate sensitivity may be in error.
• These disjunctions have likely led governments to implement policies to suppress GHG emissions that are more stringent than necessary, imposing costs beyond likely attainable benefits, and imposing regulations on Canadians that grossly compromise their economic freedom and the benefits they would gain from a stronger, less regulated, and over-taxed Canadian economy.