While covering the United Nations Climate Change Conference in Copenhagen, I took a morning away from the main venue to attend a forum of "climate skeptics".

The speakers presented political, economic, and scientific analyses to counter the series of assessments by the UN Intergovernmental Panel on Climate Change (IPCC).

A few of the skeptics went so far as to suggest that the current international drive to tackle global warming would eventually lead the world into some kind of "energy tyranny". One even showed a video clip of how "energy police" would invade private homes in the American suburbs, unplugging and removing the owners' microwave ovens, television sets, and other appliances.

I left the forum before the morning session ended. I felt that most of the speakers were too emotional and politically charged to be considered objective.

But I was impressed by the presentation of Dr Fred Singer, an atmospheric physicist and founding director of the US Weather Satellite Service, who challenged the IPCC findings with his research data.

In the next few days, I talked with several scientists, including Dr Rajendra Pachauri, the IPCC chair, and asked them about Singer's data. All of these scientists brushed aside Singer's arguments, saying that the IPCC's primary finding is indisputable: "Warming in the climate system is unequivocal".

I believed the IPCC reports, which summarize the research of some 4,000 scientists, but I had some serious reservations. For one thing, the IPCC reports contained very little data from Chinese researchers. I was told the IPCC refused to consider Chinese data because the Chinese research was not peer-reviewed.

China is not a small country. Its landmass spans several climate zones and includes the roof of the world. I have to wonder how data from China would affect the IPCC's findings.

Several Chinese scientists who have gone over the IPCC report believe that the IPCC may have overstated the link between global temperature and CO2 in the atmosphere.

In a paper published in the December issue of the Chinese language Earth Science magazine, Ding Zhongli, an established environmental scientist, stated that the current temperatures on earth look normal if global climate changes over the past 10,000 years are considered.

Ding's paper highlighted the fact that in its policy suggestions, the IPCC offered solutions that would give people in rich countries the right to emit a much higher level of greenhouse gas per capita than people in developing countries. It in effect set limits on the economic growth of developing countries, which will result in furthering the gap between rich and poor countries."

A series of "climategate" scandals now add more reason to give the IPCC research closer scrutiny.

Last November, hackers revealed that some scientists had favored data which supports the case for "global warming" in order to enhance their grant proposals.

Just last week, the IPCC announced that it "regrets the poor application of well-established IPCC procedures" in a claim that glaciers in the Himalayas could melt away by 2035. Instead of coming from a peer-reviewed scientific paper, the statement was sheer speculation, the IPCC conceded.

Then over the weekend, the media revealed that the IPCC had misrepresented an unpublished report, which it said linked climate change with an increase in natural disasters. However, the author of the report, Dr Robert Muir-Wood, clearly stated the opposite: "We find insufficient evidence to claim a statistical relationship between global temperature increase and catastrophe loss." Muir-Wood is not a climatologist, but a researcher in risk management.

I am particularly troubled by the fact that top IPCC officials do not seem to take these revelations seriously. Interviewed by the BBC, Jean-Pascal van Ypersele, vice-chairman of the IPCC, dismissed the matter as a "human mistake".

Ancient Chinese considered three a breaking point. They could forgive two errors, but not a third. Now that the IPCC has admitted three "human" errors, isn't it time scientists gave its work a serious review?

E-mail: lixing@chinadaily.com.cn

(China Daily 01/28/2010 page9)