Geoscience of Climate Change: Understanding the Climate System, and the Consequences of Climate Change for the Exploitation and Management of Natural Resources

Sponsors

Canadian Society of Petroleum Geologists,Geological Association of Canada, Canadian Federation of Earth Scientists, Royal Society of Canada.

General Chair and Technical Program Coordinator

Andrew D. Miall

Organizing Committee

Steve Grasby, Elisabeth Kosters, Jeff Packard, and Ian Young

Technical Advisors

Bill Ruddiman, Dick Peltier

The modern world is faced with two significant and interrelated problems: a climate system that appears to be undergoing rapid change, and a growing economy that will soon have to deal with the rapid depletion of its most important energy source: readily available and inexpensive oil and gas. A survey was initiated in 2005 to explore the knowledge and opinions about these issues amongst Canadian earth scientists, focusing on the members of the Geological Association of Canada and the Canadian Society of Petroleum Geologists. Some of the major results of this survey will be reported at forthcoming annual meetings of these societies (Miall and Miall, 2008).

The history of the earth’s climate is one of continual change. Many natural processes contribute to this change, including long-term forcing related to the movement and elevation of the earth’s continental plates, changes in the amount and distribution of solar radiation received by the earth driven by regular changes in the earth’s orbit and by changes in the sun’s activity, and climatic modulations driven by periodic and episodic oscillations in the pattern of oceanic and atmospheric currents (Ruddiman, 2008).

There has been a sense amongst many earth scientists that the geological history of climate change has not been a major influence on the work of the Intergovernmental Panel on Climate Change (IPCC). Comments such as “The climate has always been changing; what’s so special about the last few years?” are commonly heard at the water cooler. The first three assessments did not specifically address the issue of paleoclimates, but a chapter dealing with this issue is now included in the Fourth Assessment, published in April 2007. However, earth-science data have, from the beginning of the work of the panel, been a major factor in the developing understanding of the climate system. For example:

• The overriding importance of orbital forcing (the Milankovitch mechanism) in governing glacial to interglacial changes on a 105-year time scale. (Ruddiman, 2008).
• The Heinrich ice-rafting events in the North Atlantic Ocean, and the insights they have provided into thermohaline circulation during ice-house conditions (e.g., Alley, 2007).
• Raised beaches and coral terraces and the information they have provided about continental ice cover, ocean water temperatures, and sea-level change (e.g., Peltier and Fairbanks, 2006).
• The discovery and documentation of millennial-scale oscillations of climate change in ice cores (Dansgaard- Oeschger cycles) and deep sea sedimentary records (the so-called Bond “cycles”) have raised important questions about climatic forcing and solar influences on climate at the millennial scale (Alley, 2007).

The IPCC has focused on Holocene climates for the very good reason that it is the particular climatic sensitivities of an icehouse world that are being affected by anthropogenic forcing. Earlier climatic conditions, such as the sudden temperature spike of the Paleocene-Eocene Thermal Maximum, can also provide important information about the response of the climate system to sudden forcing.

There is now a global consensus amongst most scientists that the climate is currently being modified rapidly by the anthropogenic addition of greenhouse gases to the atmosphere, a consensus largely shared by Canadian earth scientists (Miall and Miall, 2008). The level of carbon dioxide in our atmosphere is now greater than at any time in the past 800,000 years. But it remains unclear whether any significant component of current changes in climate can be attributed to natural causes.

One of the most important ways to evaluate current models of climate change is to thoroughly explore the record of change through the last few millennia (see Mann, 2007). This is an exercise for the geosciences, and it is the first of two major objectives of this conference to examine this record and work towards a better understanding of what it tells us about the dynamics of the climate system at all physical scales and time scales. There is a rich record of paleoclimatic variability and an array of techniques for evaluating climate history, based on the study of landscapes, preserved sediments, soils, cave deposits, marine and other drill cores, ice, tree rings, and other records. Only by working from such an understanding can we reliably evaluate the contribution being made to climate change by anthropogenic processes.

The major cause of greenhouse gas increases is the combustion of fossil fuels, and there is an increasing realization that means must be found to increase the efficiencies in our use of fossil fuels and bring about substantial net reductions in their use in the coming decades. This presents a twopart problem: worldwide economic growth is increasing rather than reducing the use of fossil fuels, and such growth is leading to an accelerating depletion of these resources, with many experts predicting a decline in the availability of inexpensive oil and natural gas within the foreseeable future. Similar problems are emerging with the other crucial natural resource: water. Impending shortages there f o re comprise a second equally important reason for reducing the use of fossil fuels, and it is the second major objective of this conference to review the state of the supply, and to discuss energy sustainability, and some of the major environmental issues associated with the exploitation of coal and oil sands.

The Gussow-Nuna Conference will consist of two and one-half days of invited oral presentations. Additional presentations by poster-display are to be solicited from the geosciences community. The conference will conclude with a one-day field trip to examine the record of Late Quaternary climate change in the Banff-Calgary area (see Figure 1).

All those interested in the science behind evolving social and economic policy may wish to consider attending this event. Registration will be limited.