IPCC chairman Rajendra Pachauri faced calls to quit after errors were found in a key report. Credit: S. DAS/PANOS

After months of soul-searching, the Intergovernmental Panel on Climate Change (IPCC) has agreed on reforms intended to restore confidence in its integrity and its assessments of climate science.

Created as a United Nations body in 1988 to analyse the latest knowledge about Earth's changing climate, it has worked with thousands of scientists and shared the Nobel Peace Prize in 2007. But its reputation crumbled when its leadership failed to respond effectively to mistakes — including a notorious error about the rate of Himalayan glacier melting — that had slipped into its most recent assessment report (see Nature 463, 276–277; 2010).

That discovery coincided with the furore over leaked e-mails from the University of East Anglia's Climatic Research Unit in Norwich, UK (see Nature 462, 397; 2009). Some e-mails seemed to show that leading climate scientists, who had contributed key findings to previous IPCC reports, had tried to stifle critics. This put the panel — especially its chairman, Rajendra Pachauri — under intense pressure. The InterAcademy Council, a consortium of national science academies, was commissioned to review the structure and procedures of the IPCC and to suggest improvements to its operations (see Nature 467, 14; 2010).

The council identified the lack of an executive body as a key factor in the IPCC's failure to respond to the crisis. It also urged the panel to improve the transparency of its assessments and to make its communication and outreach activities more professional. The IPCC adopted several minor changes at a meeting last October (see Nature 467, 891–892; 2010).

More substantial reforms were signed off last week in Abu Dhabi at a meeting of dele­gates from IPCC member states. An executive committee will be created to oversee the body's daily operations and to act on issues that cannot wait for full plenary meetings. The 13-strong committee will be led by the chairman, and includes the vice-chairs and co-chairs of its working groups and technical support units.

A new conflict-of-interest policy will require all IPCC officials and authors to disclose financial and other interests relevant to their work (Pachauri had been harshly criticized in 2009 for alleged conflicts of interest.) The meeting also adopted a detailed protocol for addressing errors in existing and future IPCC reports, along with guidelines to ensure that descriptions of scientific uncertainties remain consistent across reports. "This is a heartening and encouraging outcome of the review we started one year ago," Pachauri told Nature. "It will strengthen the IPCC and help restore public trust in the climate sciences."

The first major test of these changes will be towards the end of this year, with the release of a report assessing whether climate change is increasing the likelihood of extreme weather events. Despite much speculation, there is scant scientific evidence for such a link — particularly between climate warming, storm frequency and economic losses — and the report is expected to spark renewed controversy. "It'll be interesting to see how the IPCC will handle this hot potato where stakes are high but solid peer-reviewed results are few," says Silke Beck, a policy expert at the Helmholtz Centre for Environmental Research in Leipzig, Germany.

The IPCC overhaul is not yet complete. Delegates postponed a decision about the exact terms of office of the group's chairman and head of the secretariat. Critics say that these terms should be strictly limited to the time it takes to produce a single assessment report, about six or seven years. With no clear decision on that issue, Pachauri could theoretically remain in office beyond 2014, when the next full report is due for release.

But the Indian economist says he has not considered staying on that long. "My job is to successfully complete the next assessment," he says. "That's what I'm solely focused on."