Living with Global Warming

Studies | Global Warming

No. 278
Wednesday, September 14, 2005
by Indur M. Goklany


1The 1997 Kyoto Protocol is an agreement among a number of countries to reduce emissions of greenhouse gases — principally carbon dioxide (CO2) — thought to be warming the earth’s climate. The agreement pledges 38 developed nations to control their CO2 emissions by varying amounts so that their cumulative emissions between the years 2008 and 2012 would be about 5 percent below 1990 levels. The Protocol entered into force in February 2005. The United States chose not to participate, in part because it exempts developing countries such as China and India, although they have the world’s fastest growing economies with emission growth rates to match. As we will see in greater detail below, meeting the Protocol’s targets for lowering emissions will have little effect on climate change or on reducing its impacts, despite inflicting substantial economic pain.2

"The Kyoto Protocol will barely affect, let alone halt, global warming."

According to the Intergovernmental Panel on Climate Change (IPCC), the estimated cost of the Kyoto Protocol to participating countries in 2010 would range from 0.1 percent to more than 2 percent of their cumulative gross domestic product (GDP).3 In this analysis I will assume that its cost will be at the lower end of this range — 0.5 percent of their cumulative GDP, or about $165 billion in 2010 (in 2003 dollars).4

However, by themselves, the reductions under the Protocol will not stabilize, much less reduce, the current level of atmospheric CO2. Kyoto implicitly hopes that subsequent agreements will include the larger developing countries, and that future reductions will be much more drastic. In fact, the IPCC suggests that under some scenarios cumulative CO2 emissions during this century would have to be reduced by 60 percent merely to stabilize atmospheric CO2 concentrations at twice today’s level — that is, 750 parts per million (ppm).5 Such deep reductions, however, would only reduce the rate of warming rather than prevent it.

"Mitigation through drastic emissions cuts would cost trillions of dollars."

Climate change is mainly projected to add to existing problems, rather than create new ones. Of particular significance are four categories of hazards to human health and safety which have frequently been cited as major reasons for controlling greenhouse gas emissions: malaria, hunger, water shortage and coastal flooding.6 To this list, one must add potential threats to biodiversity such as loss of wildlife habitat. This paper examines whether these problems can be ameliorated more efficiently by: (a) mitigation of greenhouse gas emissions through either the Kyoto Protocol or efforts to stabilize the atmospheric concentration of CO2; or (b) adaptation, through efforts to reduce the vulnerability of societies to climate-sensitive hazards — whether those hazards are caused by climate change or other factors. This analysis is limited to the short and medium term because long-term socioeconomic scenarios extending beyond 2085 are not credible.7 Consequently, it will not consider potentially high-impact, low-probability events such as a radical change in oceanic currents (specifically, the thermohaline) or complete melting of the Greenland or West Antarctic Ice Sheets. These are unlikely to occur during this century.8

"Spending less than $10 billion a year to adapt to climate change is far more beneficial than spending $160 billion a year on the Kyoto Protocol."

Except where noted, this paper adopts the results of recent studies sponsored by the United Kingdom’s Department of Environment, Food and Rural Affairs (DEFRA) or its predecessor agency, the U.K. Department of the Environment, Transport and the Regions (DETR).9 It does so mainly because their results, available in the peer-reviewed literature, have been used to justify additional and more rapid control of greenhouse gases.10 Notably, the authors of these studies are in good standing with the IPCC. They include Martin Parry, the current chairman of IPCC’s Work Group 2, which is charged with producing the IPCC’s upcoming assessment of the impacts of climate change, as well as several “lead authors” of various chapters of that assessment.

Nevertheless, there are significant shortcomings in these studies. In particular, their analyses of projected impacts do not adequately account for the improved range of social responses that would result from the higher level of economic development they assume in generating future emissions scenarios and climate change projections. Specifically, increased economic development should reduce society’s vulnerability to climate change because greater wealth will allow it to develop and obtain the technologies necessary to reduce the adverse impacts of climate change, while also taking advantage of any opportunities that climate change might offer.11 In other words, economic development increases “adaptive capacity.” Nor do these studies account for the technological innovation that would necessarily occur over time and as societies grow richer. This, too, should reduce the future vulnerability of societies to the impacts of climate change.12 Consequently, the DEFRA-sponsored studies are internally inconsistent with the emission growth scenarios on which they are based, and their impact estimates are probably biased upward.13

"Adaptation can solve the problems of malaria, hunger, water shortage, coastal flooding and habitat loss more effectively and certainly than emissions reductions."

This paper will examine the impact of climate change under five emission control scenarios. In order of increasing stringency, they are: unmitigated emissions, the Kyoto Protocol, stabilization of atmospheric CO2 at 750 ppm in 2250, stabilization at 550 ppm in 2150, and, as a baseline, “no climate change.” Under these scenarios the increase in the global mean temperature between 1990 and 2085 would be held to 3.2°C, 3.0°C, 1.8°C, 1.4°C and (of course) 0°C, respectively.14

In this analysis, the magnitudes of the problems of malaria, hunger, water shortage and coastal flooding are measured by the global population at risk or suffering from the specific hazard. The magnitude of the problem of biodiversity loss is measured by global losses in the extent of forests and coastal wetlands.

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