In the case of other errors pointed out, the Intergovernmental Panel on Climate Change (IPCC) report is even less at fault. The UK’s Sunday Times carried a tendentious story titled ‘IPCC Wrongly Linked Global Warming to Natural Disasters’. The story was splashed by several other media outlets, including Indian newspapers. But the article was prompted by some social scientists casting doubts on a statement supposedly made in the IPCC report on high economic costs of natural disasters, not on anybody questioning the linkage between climate change and extreme weather events!
IPCC/AR4 makes no definitive statement on economic costs beyond the observation that “extreme climate events… can cause significant loss of life and property damage in both developing and developed countries”. IPCC reports are famous for their qualifying statements and predictions in probability rather than in absolute terms. Here, too, the report says some studies show negative economy-wide costs, while others do not, that there are many complex factors affecting costs appraisal of, say, near-term agricultural impact, and that “there is uncertainty associated with the assessment of economic impact of climate change”.
Several issues have indeed been raised by the controversies over different statements in IPCC/AR4, but none of them contradict the core assessments that climate change is real and man-made, that global average temperatures are rising, that atmospheric concentrations of carbon dioxide and other greenhouse gases are increasing and that these will have serious consequences for humanity. On these, there is scientific consensus. More than 17,000 published and peer-reviewed papers have been taken into account and over 3,000 scientists have been involved in writing AR4. No other scientific exercise hitherto has involved such extensive and inclusive work. The message of IPCC is incontrovertible, the attempt here is to shoot the messenger.
It must be noted that from the very beginning of the climate debate, there has been a concerted effort to discredit the science and scientists backing the idea of anthropogenic climate change. Fossil-fuel based energy and automobile industry lobbies, the US and some other governments, right-wing think tanks and many others have been known to distort evidence, doctor reports, famously within the White House itself, and otherwise cast doubt on the growing evidence and consensus. Big tobacco did the same and produced many “scientific” studies “disproving” the link between smoking and high incidence of lung cancer. Not all climate sceptics or media reports fall into this category, of course, and several valid issues have no doubt been highlighted. But the increasingly shrill chorus of the current campaign against the IPCC and its core findings smack of orchestration.
Deficient procedures
However, none of this excuses the mistakes made in IPCC/AR4, which have resulted not so much from poor research but from inadequate review cross-checking, vital in so complex and multi-disciplinary a subject.
The peer review system has long been the established best practice in science to assess the quality of research and its findings. Yet, it also carries some inherent dangers, especially when not practised scrupulously. The peer review system is often abused by hand-picking of reviewers with favourable views on the research subject or friendly relations with the scientist in question. Old boys’ networks, cronyism and mutual back-scratching have long plagued research, as academics and researchers in India know only too well!
With over 90,000 reviewers’ comments, and with multiple authors for different chapters, IPCC/AR4 may have built in fairly good checks, but, obviously, not foolproof. The glacier data cited was from just one scientist, and it is not known what other reviewers had to say then, but, afterwards, many Indian and other glaciologists raised serious questions. But as Dr Murari Lal observed, the mistake in the report was made not by just one or a few scientists but went unnoticed by the many hundreds of authors and reviewers involved! IPCC peer review in future must go beyond a few reviewers, and procedures need to be evolved to enable the wider scientific community to also read and comment on reports. Mistakes may still occur, but not for want of doing everything possible to check them.
Excerpts from an article in People’s Democracy, an organ of CPI(M), on February 14, 2010