I am a scientist, and have spent most of my adult life trying to deepen my understanding of natural processes. I began my career in a world that had been dramatically improved by scientific knowledge, which had given us clean drinking water, sanitation, increased food production, new energy forms and communications. Resources seemed unlimited and we were led to believe that human ingenuity would allow the rapidly growing human population to enjoy the benefits of technical advance.

Today, the world’s scientists are issuing increasingly urgent warnings about the impact of human activity on natural systems. They have joined environmentalists in loudly calling for change. Given the natural caution of the scientific community and the fact that many of today’s leading scientists grew up in the same optimistic era that I did, the shift is remarkable.

Two global events in the early 1970s shattered forever the complacent assumption that the future was inevitably a linear extension of the past. The first shock was a resource issue. The Organisation of Petroleum Exporting Countries (OPEC) decided that its members were not getting a fair return for the oil they were selling to the affluent world and imposed an embargo on production. Fuel retailers ran out of supplies and the world market price for oil increased dramatically, from less than US$2 per barrel in 1972 to nearly US$30 by 1980.

Thanks to Peter Nicholson at <i>The Australian</i>”  ></p>
<p><span><small>Thanks to <a href=Peter Nicholson at The Australian

Finally, OPEC increased production and demand was reined in by conservation measures, so the crisis was resolved and oil prices actually declined. Some decision-makers reverted to the assumption that resources were unlimited. But those who had their eyes open in the 1970s saw a preview of the future.

The second ‘event’ was a report. In 1968, a group of academics and business executives formed an organisation that became known as the Club of Rome, to explore future issues. Its first report, Limits to Growth, caused a storm. Its findings have been so demonised by economists and politicians that there is a widespread perception that ‘the Club of Rome got it totally wrong,’ as one senior public servant said to me.

The report was based on the first integrated global model that included driving forces like population and economic growth as well as resource demands, various forms of production (including agriculture, mining and manufacturing) and the emerging issue of waste or pollution. It was essentially a mathematical representation of the world’s future.

It concluded that if the existing trends of exponential growth in population, resource use, manufacturing, agricultural output and waste production were to continue, we would reach limits to growth within 100 years (that is, by the 2070s). The report then said that no trend was inevitable, concluding that it was entirely possible to redirect the pattern of human development so that our civilisation would be sustainable into the distant future.

These conclusions now seem very sensible, but at the time the report provoked a response that was almost hysterical in its intensity. The underlying reason for the intensity of the response was, in my view, because it challenged the fundamental myth of modern society: unlimited growth.

The second part of the warning from the Club of Rome was that we could produce increasing amounts of waste that would disrupt natural systems. There had been some earlier examples of the problem, such as the Great London Smog of 1952, when coal smoke combined with fog to blanket the city in a cloud so thick that visibility was less than a metre, and thousands died.

In the 1950s, the then chief economist of the UK National Coal Board asked if the dramatic increase in the burning of coal could be changing the atmosphere and affecting the climate. At the time there had been no measurements, but the query stimulated the beginning of data collection as part of the International Geophysical Year in 1957. This marked the scientific community’s first steps towards coming to grips with climate change – first by collecting the data, then by modelling the changes we have set in train, and most recently by warning the community of the dangerous path we are on, and that drastic action to reduce greenhouse gas emissions is urgently needed.

In 2004 and 2005, the conclusions of two major scientific reports have sounded an urgent wake-up call about the environment. The International Geosphere-Biosphere Program (IGBP) summarised 10 years’ work by scientists around the world in its book Global Change and the Earth System. It warned that human activity is measurably altering the great natural cycles of the planet: the carbon cycle, the nitrogen cycle, and the water cycle. ‘Global change is more than climate change,’ it said.

The IGBP report warns that our interference in the nitrogen cycle might be seen in future to be just as serious as our impact on the carbon cycle. It points out that the extra carbon put into the atmosphere by human activity is only a small increase on natural flows, whereas human use of nitrogen now far exceeds the natural flows. That is, the amount of nitrogen we remove from the atmosphere, turn into fertilisers and distribute into waterways, is now greater than the amount extracted by all the vegetation on Earth.

Our interference in the water cycle is also prodigious. Humans now use about half of the available fresh water on the planet. Over the last 50 years, major dams have been built around the world at the rate of one a day. The flows of carbon, sulphur and nitrogen into our waterways are measurably changing the chemistry of the oceans. We are now a significant geological agent, shaping the future of the Earth.

The Millennium Assessment Report was released in March 2005, culminating a process begun by the UN Secretary-General, Kofi Annan, five years earlier. The report was prepared by 1360 experts from 95 countries; I was one of the 850 scientists asked to review the work before it was published. The report identified three main problem areas, and concluded that our consumption is disturbing natural systems so much that we can’t confidently predict the eventual consequences.

Our understanding of the complex natural systems of the Earth is still primitive; a contemporary US biologist memorably described it as ‘islands of understanding in an endless sea of mystery’. Because the questions are complex and our understanding is incomplete, there will always be some division within the scientific community, some cautious scientists who say that the issue is still too uncertain to alarm the public. The evidence has to be truly overwhelming to persuade the scientific community to issue the sorts of concerted warnings that have been issued recently.

The media loves controversy and tends to choose one person from each side of any dispute, even if one represents 10,000 scientists who support the accepted view and the other is one of five who don’t. In the case of climate change, one can still get the impression from commercial media that the science is hotly contested, whereas it has been almost universally accepted for at least five years. The reports described above are only the most recent and the most definitive statements of the scientific community’s increasing concern.

It is important to remember that scientists have traditionally been reluctant to emerge into the limelight and speak out on public issues. But the urgency of the situation now compels us to shout a warning. We see our civilisation unwittingly stepping in front of an ecological lorry that is likely to flatten us.

A recent book, Collapse, by US biologist Jared Diamond, is sub-titled Why societies choose to fail or survive. Diamond compares a number of earlier civilisations that collapsed with others that faced up to their problems and survived by making fundamental changes. He shows that a society’s capacity to manage a concerted response to its problems depends on cultural values and social institutions, including political structures and economic practices. So our fate is not a matter of chance, but a result of how we choose to live.

In the field of futures studies, the idea of back-casting has become popular: instead of trying to forecast the future from where we are, this approach tries to work out the chain of events that would lead us to some specified future. In the emerging area of sustainability science, this approach is being used to try to circumvent disastrous outcomes.

If we can identify future situations we want to prevent, we may be able to think of ways to avoid going down that path. If we can agree on where we want to go, we will be able to have a sensible discussion about how to get there.

While it won’t be easy, I am incurably optimistic about the future. I don’t discount the difficulty of change, but history shows that human societies can shift radically when we realise the need. I think the case for a new approach is now overwhelming.

This is an edited extract from A Big Fix: Radical solutions for Australia’s environmental crisis
Published by Black Inc

Launched in 2004, New Matilda is one of Australia's oldest online independent publications. It's focus is on investigative journalism and analysis, with occasional smart arsery thrown in for reasons of sanity. New Matilda is owned and edited by Walkley Award and Human Rights Award winning journalist Chris Graham.