This text was written some years ago, and I digged it up from my archives. Now I "recicle" it here. It is surprising, how actual it actually still is!
Introduction
The global temperature and volume of greenhouse gases are rising in the atmosphere (e.g. Merritts et al. 1996, Murck et al. 1997, Skinner & Porter 2000). A discussion on the climate change ad its consequences is intense among the researchers, governments, general public and NGOs. The Intergovernmental Panel for Climate Change advocates for anthropogenic influence on global warming, and ask for reduction of greenhouse gas emissions. However, the industry and the US government do not accept this view and want to continue with the greenhouse gas emissions without restrictions. Many geologists follow this view. Many factors may influence such positions. Some of those and resulting attitudes are discussed in this work. The work is a contribution for the debate on climate change from the geological point of view. It is based on a recent discussion held at the geological review Geologi, published by the Geological Society of Finland (Eerola 2002a,b, Eerola 2003, Winterhalter 2002, 2003, Lehmuspelto 2003).
The anthropogenic global warming as a paradigm
The man made influence on global warming is a hot paradigm. However, there are many scientific uncertainties and lack of knowledge on many issues related with the climate prediction and modeling (Merritts et al. 1996, Murck et al. 1997, Skinner & Porter 2000, Winterhalter 2002). Although the paradigm is questioned, there are no proofs against it. However, frequently such uncertainties are not taken in account in the debate, nor the climate changes that occurred in the geological past. It should be considered that the global warming might be a natural phenomenon related with the thermal fluctuations in the inter-glacial stage in which we live. In fact, we are expecting a new glaciation (Merritts et al. 1996, Skinner & Porter 2000).
Geology and the climate change
Surprisingly, geologists have been mainly absent from the public discussion on the subject, although they have a central role in it. This role is a little bit controversial, because they explore fossil fuels, whose use is believed to contribute to global warming. They also interpret the Earth’s history, where many naturally driven past global changes have been recorded. Although the environmental awareness reached the scientific community, and geology has a fundamental role in understanding the environment, environmental aspects were not considered in the educational formation of geologists until very recently. Due to those facts and related uncertainties, many geologists do not accept the man made influence on global warming and oppose to greenhouse gas emission reductions that would restrict economic activities (e.g. Winterhalter 2002, 2003, Lehmuspelto 2003). They believe that the global warming does not exist, or it is a temporary, short time and/or a natural phenomenon. They try to proove that the paradigm is incorrect, sometimes with the support of gas and oil industry. This is a social representation based on skepticism with strong economic, ideological and subjective interests involved. Those interests and attitudes are very questionable in science, although might be common (Kuhn 1962, Feyerabend 1975). In all cases, geology offers fundamental aspects which should be taken in account in any debate concerning global changes in the past, now and in the future (Young 1991, Eerola 2002a).
Past climate changes
Drastic global changes occurred also in the past. Geologists could read those in the geological record. Those changes were completely natural, without human influence. There were many mass extinctions, glaciations, desertifications, sea level variations and catastrophes. Although we have much to learn with the past climate changes (Young 1991), we unfortunately do not know sufficiently about them, their causes and consequences.
The most dramatic climate change occurred at the Neoproterozoic-Cambrian transition, where there was a shift from icehouse to greenhouse conditions (see Young 1991, Hoffman et al. 1998, Eerola 2001). The most severe glaciations occurred during the Neoproterozoic and the Earth was a “snowball planet”, covered by glaciers even in the tropics (Hoffman et al. 1998). Those glaciations exerted a major environmental pressure on organisms. The breakup of a super continent and global warming in the Cambrian caused a major environmental change and evolutionary radiation (Hoffman et al. 1998, Zhuravlev & Riding 2001).
Climate changes have occurred many times during the geological history, with negative and positive impacts. They are normal to the planet’s behavior (Young 1991, Merritts et al. 1996, Murck et al. 1997, Skinner & Porter 2000). However, it seems that there is no knowledge about that among the general public and decision makers. Those have not been sufficiently considered in the debate on climate change (Eerola 2002a).
Global change and the risk society
The global climate is a complex system that we do not fully understand. There are many uncertainties concerning the relationship between the carbon dioxide sinking and warming, such as the role of oceans, tectonics, vegetation, volcanism, water vapor and clouds in the climate (Merritts et al. 1996, Murck et al. 1996, Skinner & Porter 2000). The climate is a chaotic system. Man is just a part of it. The fact is that the man made influence is occurring very rapidly, in a question of some hundreds of years, liberating organic carbon to the atmosphere, which was sunk and stored during millions of years in coal and oil deposits. This is very much faster than the natural processes caused by geological forces (Merritts et al. 1996, Skinner & Porter 2000).
The current global warming will have many positive and negative consequences. Although there are no safe proofs about the anthropogenic influence on it, we cannot take risks and just wait to see what would happen (Merritts et al. 1996, Eerola 2002b). The related uncertainties are, in themselves, a threat to be considered (Niini 2002) and the price of the risk may be too high that it cannot be taken (Merritts et al. 1997, Eerola 2002b). Therefore, serious research on the subject and measures to reduce greenhouse gas emissions must be made. However, if this does not work, the question will be about adaptation to new conditions, as has occurred so many times during the geological history (Eerola 2002a).
Conclusion
Serious, impartial and multidisciplinary efforts should be made in order to test if there is an anthropogenic global change going on or not. Geologists should actively participate on it.
As the geology is fundamental for understanding our evolving Earth, geoscientists should also tell for the general public what they know about the past global changes and what they think about the present and future changes. There is a place for divulgation of geosciences (e.g. Hirvas & Nenonen 1990, Eronen 1991, Taipale & Saarnisto 1991, Eerola & Eronen 1998, Winterhalter 2001, Eerola 2002c), with a fundamental role in environmental education. It would give more perspective for the debate and could avoid excesses from the opposite parts of the discussion (Eerola 2002a, submitted).
References
Eerola, T. 2001. Climate changes at the Neoproterozoic-Cambrian transition. In: Zhuravlev, and Riding, R. (Eds.) The Ecology of the Cambrian Radiation. Columbia University Press, New York, pp. 90-106.
Eerola, T. 2002a. The educational role of geology in the debate on climate changes (in Finnish, with English summary). Geologi 54: 3, 61-64.
Eerola, T. 2002b. Geology teaches about climate chages – or does it? (in Finnish) Geologi 54: 9-10,
Eerola, T. 2002c. Geological lessions from climate chages (in Finnish). Kumppanin uutiset http://www.kepa.fi/uutiset/kehitysyhteistyo/2220.
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Skinner, B.J. & Potter, S.C. 2000. The dynamic Earth. An introduction to physical geology. Fourth edition. New York: John Wiley & Sons, Inc., 112 p.
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Zhuravlev, A.Y. & Riding, R. 2001. The ecology of the Cambrian radiation. New York: Columbia University Press, 525 p.
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