Himalayan glaciers: how the IPCC erred and what the science says

What The Science Says:
Glaciers are in rapid retreat worldwide, despite 1 error in 1 paragraph in a 3000 page IPCC report.

Climate Myth: IPCC were wrong about Himalayan glaciers

"In 1999 New Scientist reported a comment by the leading Indian glaciologist Syed Hasnain, who said in an email interview with this author that all the glaciers in the central and eastern Himalayas could disappear by 2035.


Hasnain, of Jawaharlal Nehru University in Delhi, who was then chairman of the International Commission on Snow and Ice's working group on Himalayan glaciology, has never repeated the prediction in a peer-reviewed journal. He now says the comment was "speculative".


Despite the 10-year-old New Scientist report being the only source, the claim found its way into the IPCC fourth assessment report published in 2007. Moreover the claim was extrapolated to include all glaciers in the Himalayas." (Fred Pearce)


The IPCC made an error about the Himalayan glaciers. Section 10.6.2 of the Fourth Assessment Report (AR4) states, “the likelihood of [the Himalayan Glaciers] disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate.” This statement did not come from peer-reviewed literature, nor did it meet the IPCC standards of evidence.

The error has raised some criticisms - both legitimate and illegitimate - about the the IPCC, the AR4, and climate science in general:

Did the IPCC respond to this error quickly and diligently? The answer here is unfortunately no. According to a review by the InterAcademy Council on the IPCC processes and procedures, the IPCC took more than a month to respond to the Himalayan Glacier error, and even then did not explicitly acknowledge the error or issue a retraction. To make matters worse, it has been documented that the IPCC had responded more quickly to other supposed errors in the report (Leake, 2010; Reuters, 2010). Though the IPCC has been recognized for its scientific contributions, there is certainly room for improvement in terms of communications.

Is the AR4 terribly flawed? It is important to note that this is one error in a roughly 3000 page technical document, an error percentage similar to the Encyclopedia Britannica. The 2035 claim was not included in the Technical Summary, the Summary for Policymakers, or the Synthesis Report.

Does this error show the IPCC has an ‘alarmist’ bias – a tendency to exaggerate the negative impacts of climate change? In fact, there are far more documented instances of the AR4 being too conservative, rather than too alarmist, on emissions scenarios, sea level rise, and Arctic sea-ice melt.

Does this in anyway undermine climate science in general? To claim this error undermines the basic conclusions of climate change is absurd. The error is part of Working Group II: Impacts, Adaptation and Vulnerability, not Working Group I: The Physical Science Basis. Anthropogenic climate change is still supported by multiple lines of independent empirical evidence, and nearly every national and international scientific body.

So what does the peer-reviewed science say about the Himalayan Glaciers?

Many of the Himalayan Glaciers are retreating at an accelerating rate (Ren et al. 2006) and roughly 500 million people depend on the melt water from these glaciers (Kehrwald et al. 2008).

The IPCC made an unfortunate error in a very long technical document. Moreover, the response to this error was far from exemplary. Highlighting this error to undermine climate science, however, is a classic example of cherry picking – a dangerous game to play with 500 million livelihoods at stake.

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