Two years to climate change meltdown

Once again, the G8 leaders have disappointed environmentalists by failing to set tough goals for CO2 emissions. Yet anyone who believes that the world can afford to drag its feet any further should make a trip to Australia, where an English scientist called Jill Cainey is in charge of the Cape Grim Baseline Air Pollution Station in north-west Tasmania. As Cainey puts it: "Whether you think there's a problem with climate change largely depends on whether you have water. If you have water, you don't think there's a problem. If you don't have water, you do."

Cape Grim lives up to its name. It falls 308 feet to a windswept sea and feels like the edge of the world, but the information sifted on its clifftop has dramatic implications for our planet. The wind analysed in Cainey's flasks - "like fat glass sausages" - is judged the purest in the world, enabling her to monitor global levels of pollution.

This April I had a conversation with Cainey (right) that I count as one of the most significant I can recall. I'd last spoken to her five years ago, when she was not at liberty to make a statement on climate change, Australia not having signed the Kyoto Protocol (it did so this year). But she did tell me that concentrations of carbon dioxide had risen from 330 parts per million in 1983 to 372ppm in 2003. The danger level, she said then, was 400.

When I contacted her again on April 23, 2008, she told me the CO2 level had since risen a further ten parts to 382ppm. And she's no longer inhibited in what she says.

The climate change that we experience today is the result, explains Cainey, of carbon dioxide emissions from 30 years ago. The most recent measurement of these emissions taken at Cape Grim shows that we haven't modified our behaviour, quite the opposite.

Australia is particularly interesting for scientists like Cainey because the results of climate change are manifest. A few miles along the coast from Cape Grim, sea-level rises have caused tracts of land to become saline, no longer productive. The impact of the melting ice cap is not the only phenomenon that concerns Cainey. "We don't know how plankton will respond when the ocean desalinifies; how trees and forests are going to respond, how crops."

One example: the oceans are becoming more acidic, which means that plankton production is down. "Consequently less krill, less bigger fish." Then there's the fact that ocean currents control our weather. Farmers on Tasmania's east coast (where I live half the year) have not had water in a year. They're aware that the problem is massive.

Cainey goes on: "In the broader scheme of things, the earth is still going to be here. The question is how much life do we take with us when we go. If we don't do anything in the next two to five years to change our behaviour and stop carbon emissions, it's probably too late." I repeat this sentence because it is a sentence of death that I have not heard issued before. "If we don't do anything in the next two to five years to change our behaviour and stop carbon emissions, it's probably too late."

The need to alter radically and abruptly our behaviour is pressing, but even before the disappointing news from the G8, Cainey was not optimistic. "I was at a New Zealand carbon cycle meeting and it left me depressed. How long it takes to agree for a certain wording used in a joint statement - whether it's 'human-induced' as opposed to 'natural variation' - seems more important than doing anything about it. We're fiddling with language when we should be fiddling with our behaviour."

Our conversation leaves me with an undeniable picture of rising sea levels, salinified crop fields and centuries-long drought.

Meanwhile, Cainey has this image for a situation that involves us all: "You're sitting in your canoe in open water, nowhere near land, and it springs a leak, and you sit there and argue about whether to plug the hole with a piece of wood or cloth, and only one thing will happen unless you fix it: the canoe will sink. We're just arguing about what we might do and not fixing it." ·