Global Warming: Messy Models, Decent Data, Pointless Policy

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The apocalyptic vision of the greenhouse effect has been presented to us all through a never-ending series of printed stories and editorials, scientific documentaries, and even several full-length films. However, sound scientific evidence argues against the existence of a greenhouse crisis, against the notion that realistic policies could achieve any meaningful climate impact, and against the claim that we must act now in order to avert disaster.

Present day climatology predictive models that serve as the basis for the global warming catastrophe scenario fail to accurately simulate climate responses to greenhouse gas buildup. Scientists who work on these models are the first to point out that the models are far from perfect representations of reality, and that they are probably not advanced enough for direct use in policy implementation. Even the most sophisticated, modern-day models:

  • do not accurately couple ocean and climate patterns;
  • do not account for the effects of non-greenhouse gas buildup;
  • fail to accurately represent the role of clouds in maintaining the earth’s energy balance; and
  • misrepresent the role of sea ice, snow caps, localized storms, and biological systems.

Greenhouse gas levels in the atmosphere have risen by 40 percent over the past 113 years. Computer models predicted that this atmospheric gas buildup would have produced a minimum of 1°C warming. Temperature records indicate, however, that the earth has experienced a temperature increase of only 0.54°C; the models err by a factor of two.

Alternative explanations for the observed warming cast even more doubt on the ability of the models to accurately simulate changes in the climate. For example:

  • Nearly 70 percent of the warming that has occurred this century took place prior to 1937. 
  • Satellite-based temperature measurements reveal no planetary warming since 1979, and even suggest light cooling.
  • Temperature records indicate that the Arctic region has cooled by 0.88°C over the past 50 years, while models predicted the Arctic would experience the greatest warming.

The timing of any temperature change (day versus night) is critical in determining the severity of the greenhouse threat. A nighttime warming would lengthen growing seasons, and a lack of warming during the daytime would not force an increase in droughts. Indeed, potential benefits of a moderate warming have not been examined sufficiently.

Global warming is presented as a crisis that can be stopped or minimized with appropriate policy actions. However, the evidence suggests that realistic policies are likely to have a minimal climatic impact. Recent research also suggests that a delay in implementing policy responses will have little impact on the efficacy of global warming mitigation strategies.

It is absolutely imperative that the policies developed for the global warming issue be built on the best science available. Too often, policymakers appear to neglect and promote the scientific studies in favor of the crisis. The scientific evidence argues against the existence of a greenhouse crisis, against the notion that realistic policies could achieve any meaningful climatic impact, and against the claim that urgent action is necessary to reduce the greenhouse threat.