1. Centre for Social and Economic Research on the Global Environment, School of Environmental Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, England
2. The Tyndall Centre for Climate Change Research, University of East Anglia, Norwich, Norfolk NR4 7TJ, England
3. Centre for Development, Environment and Policy, School of Oriental and African Studies, University of London WC1H 0XG, England