TCS Daily

Assumption Function

By Nima Sanandaji - September 28, 2005 12:00 AM

Is it possible the environmentalist movement is creating yet another doomsday myth out of global warming? After all, it has a history of false alarms, most notably the claim during the 1970s that we were going to experience a new ice age and therefore should cover the North Pole with ash (so our planet could absorb more sunlight), or that 25-50 percent of all animal species would die out between 1990-2000.

But let us stipulate that our planet is undergoing a long-term increase in average temperature, either due to the release of greenhouse gases or part of a natural temperature cycle. It is important to realize that the "small ice age", a period of unusually cold temperature that lasted from around 1600 to 1850, has recently passed, so an increase in average temperature is probably to be expected. Let us also for the sake of argument assume that natural variations don't have anything to do with the potential future temperature increase, which would be due to emission of greenhouse gases only. Would it then make sense to implement the Kyoto treaty?

Remember that Kyoto alone would reduce the GDP of the US by 2.3 percent each year if it were to be implemented. According to a climate model of the National Center for Atmospheric Research that was published in Science, the Kyoto treaty would only reduce mean planetary warming by 0.19 degrees Celsius over the next 50 years. This corresponds to a cost of more than a 12 percent reduction in the US GDP annually for each degree of warming to be prevented. Is this really worth it?

Yale economist Robert Mendelsohn has estimated the effect of global warming on the US economy and expects a net benefit. In a letter to Sen. John McCain he writes:

        "Climate change is likely to result in small net benefits for the United 
        States over the next century. The primary sector that will benefit is agriculture. 
        The large gains in this sector will more than compensate for damages 
        expected in the coastal, energy, and water sectors, unless warming is 
        unexpectedly severe. Forestry is also expected to enjoy small gains. Added 
        together, the United States will likely enjoy small benefits of between 
        $14 and $23 billion a year and will only suffer damages in the neighborhood 
        of $13 billion if warming reaches 5C over the next century. Recent predictions 
        of warming by 2100 suggest temperature increases of between 1.5 and 4C, 
        suggesting that impacts are likely to be beneficial in the US."

Is it only the US that would benefit from a warmer world? Even the worst hit regions, such as India, which is plagued with monsoons, will lose 4.9 percent of GDP if the Earth were 2.5 degrees warmer. For the average global citizen, the cost would be a 2.19 percent reduction of global GDP by 2115 (Revised Estimates of the Impacts of Climate Change, William D. Nordhaus). This figure is probably an overestimation, as economies and technologies will adapt to a changing climate, and as scientific evidence is increasingly pointing to a smaller increase in temperature as the more likely scenario.

But won't our planet be destroyed by global warming? We get our visions of global warming from ideologically driven environmentalists and Hollywood movies such as Waterworld and The Day After Tomorrow, not from science and facts. The biggest hysteria over global warming is over rising sea levels, which are portrayed as a threat to our very survival. In fact, the Intergovernmental Panel on Climate Change (IPCC) estimates that sea levels will rise 8-88 cm between 1990-2100. Sea levels have risen by some 10-20 cm since 1990 already, without causing any disaster. Even the worst-case scenario is easily neutralized by spending some resources on construction, the IPCC itself estimates a loss of only 0.1 percent of global GDP by 2100.

Some island nations would experience rising sea levels as a big problem; the most common example is the Maldives. But the Maldives sea levels have actually been falling along with global warming, according to Nils-Axel Mörner, researcher in paleogeophysics and geodynamics at the University of Stockholm in Sweden:

        "On a regional scale, the Maldives research project has revealed that there 
        are absolutely no signs whatsoever on any on-going flooding of the Maldives. 
        On the contrary, a distinct sea level fall is recorded at 1970. In conclusion, 
        there are firm observationally based reasons to free the world from the 
        condemnation to become extensively flooded in the 21st century AD."

Let us for a second assume that Mörner is wrong. The cost of building a small barrier, or raising the Maldives 8-88 cm, is negligible compared to the trillions of dollars that Kyoto will cost. And remember, the Kyoto treaty will have little impact on global warming. We need Kyoto II, Kyoto III and Kyoto IV to actually stop a potential global warming due to the greenhouse effect. Does it make sense to leave the economists out of the global warming debate while relying on the most alarmist climatologists? Let us assume that the US were to implement enough treaties to reduce its GDP by 12 percent annually. The planet would be one degree colder in 2055, but how much would we have lost in technological, economic and social progress?

The author is the president of the Swedish think tank Captus and the editor of the Captus Journal (


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