Glaciers are still melting…

25 Octubre 2009

Although an estimate of the Intergovernmental Panel on Climate Ch­ange on rapid recession of  Himalayan glaciers has become a political issue in India,  its scientific foundations are quite solid.

As always happens in India, the scientific controversy over the Intergovernmental Panel on Climate Ch­ange (IPCC) estimate on the rapid recession of Hima­layan glaciers has turned into a political issue. Environment minister Jairam Ramesh has used the IPCC’s retraction of its 2007 forecast that the glaciers could disappear by 2035 to corner IPCC chairman and director of The Energy and Resources Institute (TERI) RK Pachauri and claimed that his own stand is fully “vindicated”.

Pachauri, accused by two British newspapers of abusing the IPCC—a scientific body under UN auspices—to make private gains, has reaffirmed that the Himalayan glaciers are melting. The retraction of a date for their disappearan­ce, he claims, has “streng­th­ened” the IPCC’s credibility. He says: “This one statement was the result of an error” in a 1,000-page report.

Both Ramesh and Pachauri are wrong, although also partly right. The IPCC Fourth Assessment Report, written by some 4,000 scientists worldwide, said: the Himalayan “[g]la­ciers …are receding fa­ster than in any other part of the world and, if the present rate continues, the likelihood of them disappearing by … 2035 and, perhaps, sooner is very high if the earth keeps warming at the current rate”. IPCC was supposed to use accurate references from scientific literature and peer-revi­ew all estimates.

This particular claim was attributed to a 2005 report by the advocacy group WWF, based on a 1999 interview by the British popular-science New Scientist magazine with glaciologist SI Hasnain, then at Jawaharlal Nehru University, and now with TERI. It quo­ted Hasnain as saying that Himalayan glaciers could vanish by 2035. This, in turn, seems to be a transposition of a date (2350) mentioned by a Russian scientist, VM Kotlyakov. The IPCC failed to peer-revi­ew Kotlyakov’s claim.

Now, Hasnain says that he never mentioned a specific ye­ar but said that 2035 was “speculative”. However, he st­a­nds by his assessment that many Himalayan glaciers are in poor he­alth and receding rapidly. Hasnain did not correct the 2035 figure either in 1999 or later. Indeed, he cited it in many of his recent presentati­ons. Equally clearly, the IPCC failed to cross-check sources and relied on a popular magazi­ne—as distinct from peer-revi­ewed scientific journals.

This is a significant lapse. This comes on top of the publication of hacked emails from East Anglia university climate scientists, which suggested—on one interpretation of certain colloquial expressions—that they were willing to tweak data to suit predetermined con­clusions. Although the ha­ckers belong to the dishonour­able climate-denial lobby, the disclosures were damaging to the cause of climate change remediation. This must be se­en in perspective. The climate is changing in harmful ways because of greenhouse gas emissions. There is a 50 per cent probability of global wa­rming becoming irreversible if emissions are not made to peak by 2020.

Similarly, the London Sunday Times has just revealed that the IPCC used an unpublished report, which linked global warming to a rise in natural disasters such as hurricanes and floods. The paper’s authors eventually published it in 2008, after the FAR had been released, but said: “We find insufficient evidence to claim a statistical relationship between global temperature increase and catastrophe losses.” The IPCC should not have used an unpublished source, and should have issued a clarification after 2008.

These are not the FAR’s sole errors in its section on the Himalayas. It is also wrong in its statement on the geographical area of the Himalayan glaciers, which it overstates by a factor of 16 or so.

However, none of this alters the central, overarching truth about climate change and its Himalayan impact, established by good, solid science, which I surveyed in the book An India That Can Say Yes: A Climate-Responsible Development Ag­en­da for Copenhagen and Beyond. Warming near the Himalayan glaciers is two to four times higher than in the wor­ld—although they are unlikely to disappear in 30 years. It is equally clear that one of the ma­in contributors to glacier retreat is black carbon, soot produced by the combustion of die­sel, coal and biomass, incl­uding wood, cowdung, and vegetable waste in millions of highly inefficient cookstoves.

There is lack of clarity over the rate of Himalayan glacier retreat because they have not been thoroughly studied over decades. The most reliable indicator of glacier retreat is ch­ange in mass, not glacier len­gth or snout movement. Mass-balance studies are new and relatively few in the Hima­layas. So no precise prognosis of the pace of retreat is possible. But numerous studies show that the glaciers are retreating rapidly.

Ramesh’s position oscillates between agnosticism and outright denial of glacier retreat. This is a recipe for inaction. Rather than urgently reduce black carbon emission by providing clean fuel and cookstoves to the poor, this gives the government an excuse to do nothing—at best, retreat from action into research.

This is not to defend Pa­chauri or TERI. Allegations ab­out TERI’s contracts and overseas finances must be investigated. But it would be foolish to deny the validity of the IPCC process or its overall conclusi­ons. All science is se­lf-re­flexive, self-reviewing. Cli­mate science is relatively you­ng and probabilistic. But the FAR fo­rms the foundation on which to build further—while accepting the gravity of Hima­layan glacier melting.