Speaker Petersen - EnergyDays - 3 June 2014
Assessment of Climate-Change Risks by the IPCC - The necessity to reduce greenhouse gas emissions
While various newspaper headlines used apocalyptic imagery, the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) excels in its nuance. Besides highlighting the risks from climate change, the summary of this IPCC report gives much attention to the possibilities of adaptation to climate change. Also positive consequences of climate change have been addressed. However, the scientific literature shows that the risks of climate change are greater with increasing warming than the potential benefits. For two degrees additional warming the net effect on the global economy will be negative. How strongly negative remains uncertain, but the estimates in the literature – which lie between 0.2 and 2 per cent of global income – are underestimations, also because not all losses can be valued in money. And economic losses will accelerate for increasing warming. Furthermore, the summary states that adaptation is expected to be insufficient in Africa when climate change is major at the end of the 21st century, while there are adaptation possibilities in for example Central and South America. It is questionable whether warnings and prophecies of doom help climate policy to take a step forward. I will therefore present some of the nuances in the key findings on dealing with climate-change risks. And I will explain how the problem may become a lot smaller by reducing the emission of greenhouse gases. Finally, I will reflect on the way IPCC reports are produced.
Professor Arthur Petersen is Chief Scientist at the PBL Netherlands Environmental Assessment Agency, Professor of Science and Environmental Public Policy at the VU University Amsterdam, Visiting Professor at University College London and the London School of Economics and Political Science, and Research Affiliate at the Massachusetts Institute of Technology. He studied physics and philosophy, obtained PhD degrees in atmospheric sciences and philosophy of science, and now also finds disciplinary homes in sociology and political science. Most of his research is about managing uncertainty. Since 2001, he has been a member of the Dutch government delegation to various summary approval sessions of the Intergovernmental Panel on Climate Change.