‘‘In my language there’s a saying: tall trees collect a lot of wind, and Pachauri is a very tall tree,’’ de Boer said.

‘‘Pachauri is a respected climate scientist. The IPCC did not get the Nobel for just one report but for all of its work,’’ de Boer said. ‘‘Yes, a mistake was made and IPCC has responded to the criticism,’’ he said, adding that it would be ‘‘senseless’’ for Pachauri to take the blame for it and resign.

In response to attacks mounted by climate sceptics, Pachauri has maintained that climate change remains a serious threat and that he would not resign over the mistake in just how quickly the Himalayan glaciers are likely to disappear.

In an exclusive interview to The Financial Express in late January, environment minister Jairam Ramesh had said he felt ‘‘vindicated’’ by IPCC’s goof-up on the life of the Himalayan glaciers and that India would soon have a well-equipped national agency for climate change assessment.

In the Capital for the three-day Delhi Sustainable Development Summit that kicks off on Friday, de Boer was addressing the media on the takeaways from the Copenhagen conference in December 2009 and the way forward for climate change negotiations in 2010.

De Boer said the criticism of IPCC and Pachauri had had a positive fallout in that it had helped heighten realisation around the issue of climate change. ‘‘There’s no process anywhere that's completely flawless, IPCC has a team of 2,200-2,600 scientists who also look at the scientific literature that’s out there to come to a balanced assessment,’’ he explained.

Speaking on the future of the Copenhagen Accord that was patched together towards the end of the climate summit in the Danish capital and in which the BASIC group—of which India is a part—played a crucial role, de Boer said that while it is important as an indication of political intent by a number of countries, it is important not to ‘‘overplay’’ its significance. He added that while 56 countries had agreed to the accord, 26 others had indicated their support for it. The accord, he said, should be kept in mind, ‘‘in their back pocket’’, by climate change negotiators in future meets, both formal and informal.

Stressing the importance of a broad-based consensus on any legally binding agreement, de Boer said that because climate change affects every country around the world in some way, every country wants to have a say in it. He added that there are climate change meetings being called by the various constellations, such as the BASIC group comprising Brazil, South Africa, India and China, the European bloc and the Group of Eight and the Group of 20 economies, ahead of the conference in Mexico in November 2010, but a consensus under the UN framework is only possible if these various constellations take their proposals to all the constituencies and a consensus is reached on the subject.

‘‘Taking decisions by consensus can be cumbersome, but that way people feel more committed,’’ he said.