Popular misconceptions

An increasingly pervasive faith-based approach to energy technology may be leading to misguided choices.

Perhaps no other aspect of the energy debate has attracted so much emotional discourse and questionable science as the topic of global warming.

Global warming is defined as the observed gradual increase in average global temperatures attributed to greenhouse gases that started in about 1850, coinciding with the industrial revolution. In addition to the measured temperature rise, the widely observed thinning of the polar icecaps, the worldwide erosion of glaciers, and the measurable rise in average land and ocean temperatures are strong supporting evidence.

Two opposed camps are emerging on the matter. One view is typified by CNN's Martin O'Brien's assertion that "the scientific debate is over… something must be done". This is the 'Al Gore camp', claiming that man's activities are dramatically and irreparably changing the climate. Its members vigorously support the principles of the Kyoto Treaty.

The alternative view holds that we are primarily experiencing the variability of the Earth's natural cycles. The tenor of the debate has reached such a feverish pitch that each camp hardly takes time to understand the data presented by the other. We are engaged in a global debate involving the highest political brinkmanship on an issue that should be rationally and objectively debated.

There are two important issues central to this debate: the first is to what extent man's (anthropogenic) contributions dominate the real and observed increase in global temperature. As we have seen with the popular press, the increasingly common view is that humans are largely responsible and that we are irreversibly changing the Earth's atmosphere with dire environmental consequences.

The second issue concerns the extent to which this contribution is reversible through further human intervention and environmental remediation. This question is particularly intriguing as we consider that humans' pervasive use of petroleum-derived energy sources will be substantially curtailed since such resources will exhaust by the end of this century. The relative size of the anthropogenic contribution to the total global warming process obviously determines our ability to intervene to slow, stop or reverse the process. Thus, we need to answer the key question: "Is mankind dominating the observed global warming process, or are we merely exacerbating a natural variation of the Earth's median temperature?"

Conventional wisdom

It seems to have become apparent to scientists during the 1960s that the Earth is experiencing a gradual warming. The phenomenon may have been missed previously because satellite and other tools were not sufficiently geographically distributed, precise, or numerous to track the change, which has been averaging about 0.01°C annually, worldwide. This long-term trend is very small relative to the 'noise' in the measurement. Despite this, many observers have chosen to correlate this temperature increase with the observed increases in greenhouse gases and specifically the carbon dioxide content of the atmosphere. The increase in CO2 levels is usually attributed primarily to industrial activity in the years before 1950-1970 and the rapid increase in the use of transportation fuels since then.

There is no doubt that atmospheric CO2 has increased and that an apparent approximate correlation exists between the global temperature increase and Global warming within a narrow time period. Although there is increasing certainty of the reality of global warming, the claimed correlation between the two has always been subject to misinterpretation by the environmental lobby and the media.

For example, in his popular movie 'An Inconvenient Truth', former Presidential hopeful Al Gore uses Antarctic ice core records of CO2 and temperature from oxygen isotope inferences to illustrate the correlation between the two. But a more thoughtful analysis reveals that there are a number of other climate forces besides CO2 that contribute to the change in Antarctic temperature. Gore's simplistic extrapolation of this apparent correlation forward in time puts the temperature in 2100AD at about 10°C warmer than the present, representing a calamitous outcome. This type of alarmist presentation gets sensational press coverage around the globe.

Throughout the entire period between the mid-1800s and the mid-1900s, the temperature rise seems to lead the increase of CO2 in the atmosphere, suggesting to some that global warming appears to have been a cause, rather than a result, of the increase in atmospheric CO2. This is a very important observation, assuming that additional data support it. The increase in atmospheric CO2 has been relatively monotonic but slight, and shows no relationship with the temporarily slowed rate of global warming that was recorded during 1940-1970 and is now attributed to a larger than normal presence of sulfate and other aerosols related to volcanic eruptions.

Polar ozone

Consider the example of recent low-level ozone reports in the polar regions. Beginning about six years ago, Dr Drew Shindell of NASA's Goddard Institute for Space Studies garnered increasing media attention with claims that it was the low-level ozone, not CO2, that was responsible for spring and summer warming detected in the Arctic. To quote Dr Shindell: "Instead of being this tiny player, (ozone) can be more like 30 or 40 or even 50 per cent of the cause of warming that we're seeing in the Arctic now. It's very dramatic." In 2004, Dr Shindell was widely acclaimed when he was given the 'Top 50 Scientists Award' by Scientific American magazine.

A few years later, a very comprehensive 2007 study of surface ozone in polar regions came to a much more benign conclusion: "Given the complexity of these dependencies, the sign and magnitude of the feedback of global climate change on the ozone budget over snow and at high latitudes cannot be conclusively assessed with our current knowledge of these interactions."

The illustration is not to single out one particular study or one scientist's view at a point in time, but rather to call into question the merit of extrapolating any finite set of localised data to a system as complex as climate.

It is important to consider the number of variables that must be factored into the analysis of climate models and their ability to predict accurate results.

The last 550 million years of Earth history covers significant geological events including substantial drifting of tectonic plates, five mass extinctions, the impact of large meteors, and periods of widespread glaciation. And we can see some interesting trends from this depiction.

One is the clear cooling trend that characterises the most recent 50 million years. The Late Carboniferous and Early Permian time (315-270 million years ago) is the only time period in the last 600 million years where both atmospheric CO2 and temperature were as low as they are today (Quaternary Period). There does not appear to be a strong correlation between temperature and CO2, but we might expect to see a temperature rebound to the nominal temperature of roughly 17°C over the last 300 million years. We can also see the rather dramatic range of CO2 levels that have supported the Earth's evolution, from a high of nearly 7,000ppm in the Cambrian Period to a recent low of 275ppm in about 900AD.

Colossal emission

Also consider the CO2 infusion 250 million years ago as a result of a very large venting of greenhouse gases during the Early Jurassic Period. It is estimated that a total of 27,400 gigatons of CO2 may have been transported to the surface through breccias pipes formed from tectonic collisions.

The global warming that resulted from this incursion raised global temperature by 6°C and, combined with other climatic factors, resulted in the Earth's most serious mass extinction event. We might find some comfort here as this episode was many orders of magnitude larger than the event that might be triggered by releasing all the CO2 from our fossil fuel reserves, as the recoverable supply of world coal is about 500 gigatons.

One of the frequent and more alarming claims made by proponents of the Kyoto Treaty is the impending mass extinction that will accompany our current path toward global warming. Listening to Al Gore, we get the impression that we are already on the brink of extinction with all flora and fauna. Again, some historical perspective is helpful in the context of this shrill activism. The Earth has recovered from the last mass extinction event and has responded with deeper and broader biodiversity. While it is true we live on a fragile planet, more diversity improves rather than hinders the prospects for a thriving ecosystem ahead.

John R Wilson is president of TMG Energy, an energy consulting firm that has recently been working to develop and implement numerous conventional and alternate energy technologies for a wide range of users. Griffin Burgh, ALA, LEED, is a practicing architect with a long background in solar architecture and sustainable design. His interest in alternative energy has included the design of a low-speed electric car and a project on the Fisher Coachworks Advanced Technology Hybrid Bus. They are co-authors of 'Energising Our Future', published this month by Wiley (www.wiley.com [new window]), which surveys and analyses in considerable depth the present and future economic and technical viability of oil, natural gas, coal, synthetic fuel, nuclear, hydrogen, solar, biomass, wind and less well-known potential energy sources in the context of real-world production, distribution, and environmental constraints.

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