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Histories: The week the climate changed

Twenty years ago, a conference in a sleepy town in Austria became the spark that lit today's burning concern about global warming

THERE were no journalists present, and no headlines afterwards. But at the International Conference on the Assessment of the Role of Carbon Dioxide and of other Greenhouse Gases in Climate Variations and Associated Impacts, 89 scientists from 23 countries recast climate change as a problem for today.

They declared that “in the first half of the next century, a rise in global mean temperatures could occur which is greater than any in man’s history”. They warned for the first time that the likelihood of this catastrophe happening would be “profoundly affected by government policies”. And they called for “consideration of a global convention” to tackle the threat.

“Villach was the turning point,” says Jill Jaeger, a young researcher dragooned into editing a report for the meeting. Bill Clark of Harvard University, the author of key scientific studies on climate change in the US in the early 1980s, says Villach was a “catalytic event”. “Suddenly the climate change issue became much more urgent,” agrees Bert Bolin, the leading Swedish meteorologist who oversaw the meeting’s scientific report and later became the first chair of the IPCC.

Everyone who took part agrees that the driving force was Jim Bruce, a leading climate scientist in the Canadian government and the meeting’s chairman. “It was Jim who wanted a statement from the meeting that ensured political follow-up and he coordinated the group that drafted the statement from the meeting,” says Jaeger.

And there were others behind the scenes. The meeting was co-sponsored by the UN Environment Programme, whose influential director Mostafa Tolba was fresh from brokering a global treaty to protect the ozone layer and now wanted to repeat the trick with greenhouse gases.

But more important, perhaps, was the fact that the international group of scientists met in Villach as individuals, rather than as representatives of governments or large scientific bodies. This was unusual for climate science. Until then it had been largely the preserve of government research bodies, and caution was the watchword in pronouncements on future climate change. Let off the leash, the researchers signed up to a forecast of “substantial warming” that was unambiguously “attributable to human activities”. No ifs, buts or maybes. And they felt able to make policy recommendations that their bosses back home would have vetoed if they’d had the chance.

Wendy Franz of Harvard University, who studied the evolution of climate policy in the late 1990s, reckons it is impossible to overestimate the effect of the absence of domestic political constraints. It encouraged the scientists, in the words of US meteorologist William Kellogg, to stick their necks out.

This difference was particularly marked for the Americans. They were pioneers of much of the basic climate modelling, but then, as now, they were operating under a Republican administration hostile to any suggestion of constraints on burning fossil fuels.

That made American scientists ultra-cautious. Just two years earlier, meeting under the umbrella of the US National Research Council (NRC), several of the American participants had stressed in a report to their government the “continuing scientific uncertainties” about climate change and the need for more research. The Villach deliberations made them see the urgency of their work and its implications. By the end of the conference Thomas Malone, who had chaired the 1983 NRC report, had changed his mind. He had, he said, undergone “a reversal of an opinion I held a year or so ago. I believe it is timely to start on the sensitive task of framing a convention on greenhouse gases, climate change and energy”.

“Let off the leash, they signed up to a forecast of substantial warming”

One factor in this change of perspective, says Franz, was that scientists other than atmospheric physicists and climate modellers got involved for the first time. And they were shocked by what they heard. The engineers and biologists in attendance could see the immense practical significance of what was being forecast. It seemed to them, in the words of one, “very scary”.

Some scientists who weren’t there say Villach wasn’t so important. Tom Wigley, a leading modeller then at the Climatic Research Unit of the University of East Anglia, UK, says Villach was a “waffly non-event” whose significance has been “grossly overstated”.

It is true that, among climate scientists, the story of the significance of greenhouse gas emissions and their accumulation in the atmosphere had been building for some time. Stephen Schneider, one of the first climate modellers to take global warming seriously, reckons the important modelling work was done in the US in the 1970s.

But there was new science at Villach. Bolin’s analyses showed it was not just carbon dioxide that was raising temperatures. Several other gases being pumped into the air were having a similar effect, including methane, nitrous oxide and chlorofluorocarbons (CFCs). This had a big impact on the participants because “it was bringing the likely time of significant changes in climate much closer than had been previously expected”, says Bruce.

But the change brought about by Villach was as much about personal as atmospheric chemistry. The meeting somehow generated the “wow factor” says Jaeger – the realisation that there could be significant change in our lifetimes. “While evidence for the importance of greenhouse gases had been mounting,” she says, “it was this group of scientists who mobilised around the findings and used them to justify a call for urgent action.”

The bandwagon was rolling. Gordon Goodman of the Beijer Institute in Stockholm, Sweden, went home to write a chapter on climate change for the influential Brundtland report on environment and development. That report led directly to the UN Earth Summit in Rio de Janeiro in 1992, where the UN Climate Change Convention, precursor to the Kyoto protocol, was signed.

Meanwhile other politically savvy scientists were attracted to the issue. Some, like the British atmospheric chemist Bob Watson, who went on to become a chairman of the IPCC, had cut their policy-making teeth earlier in the decade persuading politicians to tackle the threat to the ozone layer.

Climate scientists had found their voice. Within three years, a high-profile conference on the atmosphere in Toronto, Canada, was demanding a 20 per cent cut in global greenhouse gas emissions by 2005 – a target that, much watered down, became the basis of the Kyoto protocol of 1997.

There was one piece of tragi-comic fallout from Villach. Officials from the US government’s Department of Energy immediately afterwards complained loudly about the conference’s political recommendations. And they discovered that Tolba wanted to establish an independent group of scientists to monitor the issue. “The US government became alarmed that the climate agenda was being driven by a small group of non-governmental entities,” says Jaeger. So the Republican administration under Ronald Reagan worked the UN corridors, lobbying against Tolba’s plan and pushing for the creation of an Intergovernmental Panel on Climate Change, which was duly established by the UN General Assembly in 1988.

The purpose of the IPCC was to put scientists back in the cages they had briefly escaped from at Villach, and to this day the IPCC’s members remain government nominees. But it was too late. The story of global warming – and what scientists really felt about it – was out. Far from knuckling under, the Villach generation of climate scientists and their heirs have since used their new-found status as members of an intergovernmental panel to underline the urgency of tackling climate change. US administrations ever since have devoted much time to denigrating the reports of the IPCC, the body they did more than anyone to create. But the spirit of Villach lives on.