Product has been added to the basket

Oceans Apart?

The following opinion piece was first published in the January 2003 issue of the Society's magazine, Geoscientist

A forthcoming meeting convened by the Society's Petroleum Group will pit two oil industry giants (Vice Presidents Frank Sprow Exxon Mobil and Greg Coleman BP) against each other in a public debate on coping with climate change. What part will geoscientists play in this essential process?, asks Bryan Lovell *

* Bullard Laboratories, Department of Earth Sciences, University of Cambridge

In 1997 an Atlantic divide opened up in the oil industry - between those (mostly in the USA) who believe that climate change is not much influenced by mankind, and those (mostly in Europe) who think it is. Behind lies a serious scientific argument concerning the messages to be read from the geological record of climate change. A forthcoming meeting of the Petroleum Group will consider the geological record of climate change and its impacts. It will then ask what practical contribution Earth scientists can make to dealing with those impacts.

Earth scientists have played a key role in finding and exploiting commercial reserves of fossil carbon. If mankind now wishes to release less of that fossil carbon to the atmosphere, the involvement of Earth scientists inside and outside the oil majors will be a vital part of that process. For that reason, and as a perspective on the Atlantic divide mentioned above, we plan to hold a debate between senior executives of BP and Exxon Mobil.

Geologists tend to look back when they think about climate change, leaving others to look forward using computer-based models. Until the very late 20th Century, the oil industry, replete with geologists, tended to look back and reassure itself it was doing no harm1. All this changed in 1997. In April, Shell’s (1996) Annual Report stated: "There are still many uncertainties about the impact of increasing atmospheric concentrations of carbon dioxide on global climate. However, there is now sufficient scientific evidence to support taking prudent precautionary action." Earlier, in January 1997, Dr David Jenkins, BP’s Technology Director, had sent a memorandum to Managing Directors on climate change. In May 1997 the Chief Executive of BP made a speech at Stanford University that changed forever the comfortable public consensus in the oil industry2.

Although differences persist over the role of human agency, no party now seriously denies that climate change is taking place, and most agree that "stability is not an option"3. Climate changes have profoundly affected our own evolution. Cane and Molnar4 have suggested, for example, that the convergence of Australia and Asia restricted the passage of warm Pacific water into the Indian Ocean. They believe that the emergence of the Indonesian island of Halmahera 3Ma to 4Ma ago may have diverted major ocean currents and hence increased aridity in East Africa, with consequent changes in primate habitat.

Another example from older rocks suggests5 that 55Ma ago, at the Paleocene-Eocene boundary, a massive input of methane, probably caused by abrupt failure of sedimentary carbon reservoirs, pumped carbon into the atmosphere at rates similar to those induced today by human activity. There were profound effects on the ocean and atmosphere. The longevity of the isotopic anomaly in the sedimentary record suggests that the residence time of carbon was around 120 thousand years. The striking correspondence between the quantities of carbon introduced without man's influence 55Ma ago, and those now being put into the atmosphere by us, would alone justify this Geological Society meeting.

So what will make this meeting different, and perhaps of more general interest than many other climate-change conferences? I believe it is its foundation on two matters beyond reasonable dispute. First, we have the implacable constraints imposed by the geological record on modelling and speculation about future climate change. Second, throughout the conference we will recognise that climate has often changed in the past, sometimes rapidly, and will change in the future whatever Homo sapiens does.

On the first day, the emphasis will be on the geological record of climate change. Recent advances in reading the story of climate change from deep-sea sediments are given just priority. On the second day, the impacts of those climate changes will be considered - on land, in the ocean and at the coast. By the third day we can concentrate on the practical question: when we are looking for solutions to the problems caused by climate change, can geology help?

On the second evening, we revive an ancient tradition of the Society with a public debate - between senior executives from Exxon Mobil and BP: two organisations that appear to be separated by an ocean of difference in their attitude to climate change. Is that appearance reality? Why does it matter?

Oil companies may be getting greener, but they are not going to find it easy to reduce, let alone give up, their core business. This involves taking fossil carbon out of the ground, and transferring it, via some mighty useful purposes, into the atmosphere. How could an oil company maintain profitability during a retreat from fossil fuels? For non-state oil companies, shareholders and potential shareholders would exert a crucial potential veto. Could an early 21st Century oil company pursue even a medium-term strategy that explicitly aimed to reduce profit based on production of fossil fuels, without bringing about its own extinction? For state oil companies, which hold by far the greater part of Earth’s reserves of oil and gas, there are also stakeholders who would be hard to convince. These constraints appear to be unlikely to slacken.

Earth’s own internal heat is lost at about 1028 ergs per year6. That is an order of magnitude greater than the rate at which heat is released by human activities. Yet the input of heat from Sun to Earth is five thousand times greater still. The balance of surface heat is in part mediated by an atmospheric gas - carbon dioxide - the presence of which is measured in parts per million. These are beguiling numbers, controlling Earth processes that defy simple understanding, never mind confident prediction.

There may even be a fundamental pulse7 in the release of internal heat from Earth that we are only just beginning to quantify8. This pulse may at times control ocean circulation9 and hence climate. The subtlety of these various processes will not be intuitively obvious to even the best-educated non-specialist - including the economic analysts who value oil companies on the price of crude and annual production statistics.

This meeting will attempt to examine these conundrums rigorously: maybe we shall find some answers.


1Gerhard, LC and Hanson, BM, 2000. Ad hoc committee on global climate issues: annual report. American Association Petroleum Geologists Bulletin, volume 84, pages 466-471.

2Browne, EJP, 1997. Climate change: the new agenda (a presentation to Stanford University, California, 19 May 1997). Group Media and Publications, The British Petroleum Company p.l.c.

3Jenkins, DAL, 2001. Potential impact and effects of climate change. In: L.C. Gerhard, WE Harrison and BM Hanson, editors, Geological Perspectives of Global Climate Change, American Association of Petroleum Geologists, Studies in Geology, number 47, pages 337-359.

4Cane, M and Molnar, P, 2001. Closing of the Indonesian seaway as a precursor to East African aridification around 3-4 million years ago. Nature, volume 411, pages 157-162.

5Norris, RD and Rohl, U, 1999. Carbon cycling and chronology of climate warming during the Paleocene/Eocene transition. Nature, volume 401, pages 775-778.

6Press, F and Siever, R, 1978. Earth (second edition), W.H. Freeman and Company, San Francisco.

7Umbgrove, JHF, 1947. The Pulse of the Earth (second edition), Martinus Nijhoff, The Hague.

8White, N and Lovell, B, 1997. Measuring the pulse of a plume with the sedimentary record. Nature, volume 387, pages 888-891.

9Wright, JD and Miller, KG, 1996. Control of North Atlantic deep water circulation by the Greenland-Scotland ridge. Paleoceanography, volume 11, pages 157-170.