ENVIRONMENT: Hot Air over Global Warming

By Sanjay Suri and Julio Godoy Reprint | | Print |

Julio Godoy and Sanjay Suri

PARIS, Feb 19 2003 (IPS) - The Intergovernmental Panel on Climate Change (IPCC) is meeting in Paris this week in the face of a challenge to the very basis of its projections from two leading academics.

“Contrary to accepted international practice, the 40 scenarios presented in the Report convert GDP (gross domestic product) data for the countries of the world to a common measure using market exchange rates, rather than purchasing power parity (PPP) rates,” Prof David Henderson, formerly chief economist with the Organisation for Economic Cooperation and Development (OECD), a group of the world’s major industrial nations told IPS in London.

Prof Henderson, now visiting professor at the London Business School, is challenging the IPCC projections along with Ian Castles of the National Centre for Development Studies at Australian National University, and formerly head of Australia’s national office of statistics.

“Because of this flawed procedure, and also because of built-in assumptions about the extent to which the gap between rich and poor countries will be closed over this century, the scenarios yield projections of GDP for developing regions which are improbably high,” he said.

The IPCC had said in the Third Assessment Review that globally averaged mean earth surface temperature “is projected to increase by 1.4 to 5.8 Celsius degrees over the period of 1990 to 2100.” The simple link between GDP and emissions is that emissions will rise with GDP, though several experts warn that it does not follow that they will stay very closely linked, or that they will rise in the same proportion.

Prof Henderson says that even the scenarios which show the lowest cumulative emissions over the century do not in fact represent reasonable lower limits. “These projections do not, as is claimed for them, encompass the full range of uncertainties about the future,” he said. “They should not be taken as the accepted basis for the IPCC’s coming Fourth Assessment Review of climate change issues.”

Prof Henderson said: “I hope that the Panel will recognise that our critique of the Special Report on Emissions Scenarios is well founded.” He added: “What we are saying does not merely represent the views of two isolated persons – although neither I nor my co-author have any official status. What we are saying would receive wide professional backing.”

Prof Henderson said it would be difficult to repeat an exercise on this scale in time for the IPCC’s Fourth Assessment Review. “But a more limited exercise should begin now to review the basis for the work on emissions, and to arrive at a new set of projections which, though less elaborately derived, would give a sounder basis than the present figures,” he said.

Their critique goes beyond the work on emissions scenarios, he said. “More generally, we think that the IPCC should try to ensure a more balanced, informed and professional treatment of the economic and statistical aspects of its work,” he said.

“On the official side, there should be a greater involvement of economic ministries and statistical agencies. Among the academics who take part, there should be better representation of economic historians and historically-minded economists.”

Nebojsa Nakicenovic, co-author of the Third Assessment Review, and economic and statistics expert at the IPCC, said the charge against the report was unfounded. Nakicenovic is project leader at the Vienna-based International Institute for Applied Systems Analysis. = 02192131 ORP025 NNNN ZCZC ORP026 QD EU WD EN ROMAIPS ENVIRONMENT: Hot Air over Global Warming(2-E)

“We did use PPP in our estimations,” Nakicenovic told IPS in Paris at the meeting. “Our critics seem not to be aware that the IPCC proposed several alternative analyses. One of those uses PPP.”

Nakicenovic admitted that PPP is a better indicator to make comparison between countries. “But the physical world doesn’t change whether we use this or another indicator to measure emissions,” he said.

Nakicenovic said the SRES was co-authored by about 50 leading experts in social sciences, demography, economics, and statistics, and also by representatives of private sector enterprises working in fields relating to climate change.

“Prior to our evaluations, we examined the whole literature on economic development, energy, technological change, demography, and so on,” Nakicenovic said. “At the end of our evaluations, we compared our conclusions and the range of emissions we have calculated, and found them consistent with the prevailing literature.”

Rajendra Pachauri, IPCC chairperson, said at the panel’s opening session in Paris, that by underlining the gravity of the situation caused by global warming, the organisation touches extremely sensitive world political issues, such as the ratification of the Kyoto Protocol.

The treaty, named after the Japanese city where it was negotiated in 1997, calls upon major industrial nations to reduce their greenhouse gas emissions by 2012 to 5.2 percent below the levels in 1990.

U.S. president George W. Bush withdrew his country’s ratification of the Kyoto protocol immediately after assuming office in early 2001, arguing that the treaty was contrary to U.S. interests.

United States generates at least 23 percent of the world’s total carbon dioxide emissions. By 2001, these emissions had grown 18 percent above 1990 levels. According to the U.S. Energy Information Administration’s International Energy Outlook 2002, the emissions would grow by 33-46 percent over the next two decades.

“We cannot say whether the criticism of our work is influenced politically,” Pachauri said. “But the fact is that our climate is changing and the consequences are very serious. Global warming demands dramatic behavioural changes on the part of individuals and societies, and we know that these changes are difficult to accept and to put into practice.”

Pachauri recalled that some centuries ago, the London-based Flat-Earth Society used to have several thousands of members, who believe that the earth is a slice.

“The Flat-Earth Society has only a handful of members today, and they continue to meet every year, to assert that the earth is indeed a slice,” he said. “It is the same with climate change – you may deny it, but it is a fact.”

However, Pachauri told media representatives Wednesday that the panel will increase the use of PPP in its next assessment review, due to be completed by 2007.