Climate science is in a state of flux. Scientists from several disciplines are working diligently to show the effects of anthropogenic activities on global climate. As this work continues, however, many are finding that natural processes and variability effectively mask or obscure anthropogenic contributions. The major problem, in our view, revolves around the fact that current scientific activities related to climate-change issues do not adequately consider pertinent evidence available in the geologic record. These records serve as archives for evaluating such critical issues as the natural range of temperature conditions and the variation in greenhouse-gas concentration levels through geologic time.
Geologic science has a unique role in assessing the phenomena of climate change. Geology is the only discipline that routinely works backward in time to unravel facts and interpretations from materials that are hundreds of thousands, millions, or even billions of years old. Climate changes must be viewed over the same spans of time that create and drive them. Some climate changes (e.g., small-scale solar cycles) may be as short as a human life span, while others span tens of thousands to hundreds of millions of years.
This book was designed to bring into careful consideration the geologic parameters and measurements that illustrate the full range of past climate changes against which anthropogenic effects may be compared. Such a documented background is essential if the human consequences on climate are to be truly distinguished from naturally occurring variation. Most of the papers collected here are new research results that add to the already solid literature in geologic science that deals with the variability of climate. It is important that the full spectrum of science be brought to bear on this matter. It is especially important if significant national policies (e.g., U.S. adoption of the provisions of the Kyoto Protocol) are based on flawed or selective consideration of scientific investigations.
If the costs associated with significant reductions in greenhouse gases were trivial, we would have fewer reservations about developing and deploying such measures. However, the projected costs are extremely high ($315 billion per year [based on the U.S. Department of Energy’s Information Administration estimated carbon tax of $348/ton of carbon, Murphy Oil Company estimated carbon content per barrel of oil, and an assumed U.S. daily oil consumption rate of 19.5 million barrels per day] in new taxes) and the planned actions under the Kyoto Protocol appear to be ineffective, at best. Because of the enormous stakes associated with the protocol, it is incumbent upon scientists to take steps to better understand complex natural systems, how they operate, and their overall effects on climate change. Only then can anthropogenic overprints be properly evaluated and analyzed.
The editors and individual authors were not financially supported by any industrial or similar organizations. Most are academicians who design and conduct their individual research programs without regard for potential policy implications of their work. William E. Harrison and Lee C. Gerhard are employed by a state geological survey. Bernold M. Hanson, a past president of the American Association of Petroleum Geologists, is deceased. None of the contributing authors is currently a practicing petroleum geologist, although several have had broad and successful experiences in that profession.
We have made a conscientious effort to bring pertinent science to the question of climate change, regardless of whether the evidence challenges or supports the global warming hypothesis. The reader will probably note that each individual author may bring professional opinions into his or her work, but in all cases, the scientific material has been subjected to a rigorous peer-review process. Although the publisher of this book is the American Association of Petroleum Geologists (AAPG), we have worked diligently to avoid an industrial or environmental bias to the volume. From the outset, we viewed our task to be to compile the best and most appropriate scientific investigations, and to let those studies speak for themselves.
AAPG is one of the largest professional geological societies in the world, and most of its members concentrate on science that supports their quest to supply global society with energy while vigorously maintaining the highest level of environmental stewardship. Over the last 18 months, we have been privileged to be associated with numerous earth scientists who have contributed indirectly to this volume by virtue of their interest and support. These colleagues often made us aware of relevant (but sometimes obscure) scientific investigations, provided encouragement and insight, and invariably served as a critical, but frank, first audience.
Much of the work set forth in this volume resulted from oral presentations at national meetings, efforts from members of the AAPG Ad Hoc Committee on Global Climate Issues, and activities of the AAPG Division of Environmental Geosciences. We appreciate the association’s support and encouragement to continue this work and bring these studies together in a single collection of papers.
Finally, we recognize the leadership of our departed colleague, Bernold M. “Bruno” Hanson, whose inspiration and guidance always concentrated on integrity, openness, and high citizenship. He lived his beliefs of public and professional participation and responsibility. We dedicate this book to his memory, with the hope that he would have approved of what we have done.
Lee C. Gerhard
William
E. Harrison