A letter writer to a newspaper recently pleaded for guidance on how to get the facts about whether there is human-induced global warming. But the writer added emphatically that he did not want to read reports of the Intergovernmental Panel on Climate Change (IPCC) because he wanted independent and reliable information.
Now, it could just be me, but I would have thought that the world's most comprehensive assessment and review of climate science by thousands of international experts should probably be the first port of call when searching for facts.
And make no mistake about how central the IPCC is to the global warming debate. The IPCC's reports are why ours and other governments around the world are calling for reductions in greenhouse gas emissions; and why everyone will meet in Copenhagen next month.
But some of Australia's leading politicians such as Tony Abbott
and Senator Nick Minchin
have variously dismissed the IPCC as "alarmist" or fuelling a left-wing conspiracy to "de-industrialise" modern society
During a visit to NSW's Henty Field Day this year (http://blogs.abc.net.au/events/2009/09/farmers-still-sceptical-about-climate-change-science.html) I met numerous farmers' representatives who also harboured a dark suspicion of the IPCC and of climate scientists.
So is the IPCC really that kooky? Have thousands of participating scientists from around the world who've contributed to four IPCC reports since 1990 duped the world with hidden agendas and manipulated science? Have they all got it wrong?
I should point out that the IPCC's conclusions are supported in most countries by most major scientific bodies. In Australia that includes the CSIRO, the Australian Academy of Science, and the Federation of Australian Scientific and Technological Societies, to name a few.
The UN Intergovernmental Panel on Climate Change was established in 1988 by the World Meteorological Organisation (WMO) and the UN Environment Program (UNEP). It has issued four reports (1990, 1995, 2001 and 2007) each asserting with increasing certainty that the globe is warming (now 100 per cent certain) and that human driven greenhouse gas emissions are largely to blame (now 90 per cent certain). The next report is due 2014.
While it is called a 'panel,' the IPCC is actually one of the most ambitious scientific undertakings in history bringing together hundreds of scientists and other experts who are generally nominated by their governments or by non-government organisations (such as the Australian Academy of Science or the CSIRO). But the IPCC is also policy-neutral. Its job is to present the best science. There is not a single policy recommendation in its reports.
A different group of scientists is picked for each report and it is not just climate scientists - but biologists, physicists, geologists, economists, engineers, health experts and so on. Each report deals with three categories: the physical science, or how climate change works; impacts, adaptation and vulnerability, or how to deal with it; and mitigation, or how to minimise it.
Each of these working groups is headed by two scientists, one each from a developed and developing nation, supported by up to 500 other scientists known as lead authors who in turn are supported by up to 2000 further expert reviewers. Together they evaluate thousands of pieces of peer-reviewed research from around the globe.
Here is how Queensland University's Professor Ove Hoegh-Guldberg, a world expert on coral reefs and climate change, describes what happened when he contributed a small slice of the 2007 IPCC report:
"The IPCC has one of the most rigorous review processes I have ever experienced. There are various stages of review. The first round involves the working groups picking over the text (hundreds of eyes and qualified expert opinions). If you have been involved in this process, it is a quite an experience which takes months and years - involving a lot of pedantic haggling over detail - but always using the peer-reviewed literature as the base. When this is complete, then the documents are sent to signatory governments for review. Leading scientists from each of the countries pick over the details. And after this, the documents are placed for open comment (on the web). At this point, any government, industry, science group, special interest group, or individual is invited for comment, recommendations, amendments etc. In response, the lead and contributing authors are required to respond to each comment or suggestion in a precise fashion, however correct or off-the-wall they may be. The responses from the specialists are them independently reviewed to ensure that the documents have been amended to include the comment/suggestion/objection or the comment/suggestion/objection refuted scientifically (ie with peer-reviewed literature). Personally, I had to respond to 87 comments on a relatively small contribution to the Australian and NZ chapters within Working Group 2 of the IPCC report in 2007. At the end of the day, I don't think you could have a more rigorous process. The only problem is that it ends up being conservative (e.g. failure of AR4 IPCCC in 2007 to predict the current dramatic decline of Arctic sea ice). That may be its only flaw."
There were more than 30,000 comments from the open public review process for just one of the 2007 working groups - all of them given a written response that is publicly available.
One of the lead authors on the 2001 and 2007 reports, UNSW's Professor Andy Pitman, also worries it is unduly cautious especially because in the final stages all governments, including those with vested interests in fossil fuels like Saudi Arabia, have to approve what has been written "line by line."
Prof Pitman says he and others acknowledge there is much they don't know about how the earth and the climate work; that they have been wrong on some things and that they are eager to test and re-test emerging data. They are by nature a conservative bunch, he says. "All good scientists are sceptics to the core."
But so far nothing has seriously challenged their analysis of an underlying warming trend and its connection to human generated CO2 emissions. If anything, the latest data points to faster and stronger global warming.
"Don't you think ambitious scientists would love to make their name proving global warming wrong? To prove the IPCC is wrong? ," he says. "It would guarantee a Nobel prize!"
"Are we just biased and have we turned the profession into being distorted onto our side?" asks New Zealand's Professor Martin Manning of Victoria University who headed technical support for the 2007 IPCC report. "God, I wish that were the case, because I have grandchildren and practically every day I really, really wish we were wrong."
Which brings us to one of the enduring sources of frustration among IPCC and many other scientists. Just about all the scientists attacking the IPCC, Prof. Pitman says, have never researched nor published any climate science in peer-reviewed journals - and peer review is how science works.
"Climate Science is not about opinions. It is about what is provable and disprovable. There are no scientific publications that provide serious challenge to the IPCC conclusions. Not one. But there are literally thousands that support the conclusions of the IPCC."
When is science valid?
A valuable reference here is a short, sharp guide published by the Federation of Australian Scientific and Technological Societies. It's worth a look.
In part, it provides a checklist to see whether a scientific idea has been validated:
- Has it been published in the peer-reviewed literature in that field of science?
- Have other scientists cited that publication as being valid (as opposed to citing it to show that it is wrong?)
- Have other scientists conducted additional tests that show the idea to be valid?
- Has the idea been built upon to create new understanding, i.e., has the idea become useful?