UCL News


Climate change is often only the trigger not the culprit in the collapse of civilisations

13 June 2006

Climate change has often been 'fingered' as the main culprit in the demise of civilisations such as the collapse of the Old Kingdom in Egypt and the death of the Vikings in Greenland.

But evidence that will be presented at a conference hosted by UCL (University College London) this week suggests the main reason may often have been a society living beyond its means.

Professor Frank Oldfield, of the University of Liverpool's Department of Geography and a visiting professor in the UCL Environmental Change Research Centre, will present these findings today at the 'HOLIVAR 2006 - Natural Climate Variability and Global Warming' conference.

He argues that in many instances, environmental damage through the non-sustainable use of resources in marginal situations has been the deciding factor in civilisations teetering on the brink of collapse. One of the clearest and most dramatic examples is that of Easter Island, where the society responsible for the marvellous stone statues collapsed through over-exploitation of vital resources. And such examples highlight the need for a fresh assessment of how resilient present systems of social organisation are, and how important efficient resource use will be to future climate change.

"Humans have been putting pressure on the environment, at local or regional scale for many thousands of years. It is even quite likely that they were already contributing to increased greenhouses gases as far back as 8,000 years ago through cultivation and clearing of land," says Professor Oldfield.

"But if you look at societies that have faltered, such as the Vikings during the Little Ice Age that began around the 14th century, social and economic factors had a substantial role to play. The Vikings were too dependent on cultural and economic links with Europe and on a European style of living. When temperatures dropped and sea ice levels increased, they lacked the local knowledge to effectively use the resources of their homeland where they had already over-exploited the soils. This was coupled with a loss of trade; for example, walrus ivory, one of the Viking's exports, was replaced by ivory from elephants, so part of their economic base was lost.

"Today, in regions such as Sudan the effects of a long civil war are compounding the effects of periodic drought on a fragile ecosystem at the margin of sustainability. Damage to ecosystems is often rapid, but recovery is a long term process: in the rainforests of the world a brief period of exploitation will need hundreds if not thousands of years for complete recovery.

"Social scientists and climatologists have often made conflicting claims about the collapse of civilisations - the former favouring cultural explanations, the latter pointing to the dire effects of climate change, often in the shape of severe drought. The reality is there's a complex inter-relationship between the two and a fresh approach is needed if today's world is to overcome current challenges. Everyone's imagination is captured by cultural collapses but really we should devote resources to assessing why certain societies survived climate stress."

Professor Oldfield will present his keynote speech, 'The role of people in the Holocene' on Tuesday 13 June from 11.55am to 12.35pm.


For further information, please contact:

Judith H Moore, UCL Media Relations, Tel: +44 (0) 20 7679 7678, Mobile: +44 (0)77333 075 96, Out-of-hours: +44 (0)7917 271 364, Email: judith.moore@ucl.ac.uk

About HOLIVAR 2006

The conference, 'HOLIVAR 2006 - Natural Climate Variability and Global Warming' will be hosted by UCL from 12 to 15 June. It brings together international experts to discuss whether the main culprit driving global warming is human activity or just natural variations in climate systems and marks the climax of the five-year European Science Foundation funded project. Further details and a copy of the programme can be accessed at: http://www.holivar2006.org/