Climate change: The canary is singing, but is anyone paying attention? The world could be as little as 10 years away from environmental catastrophe but governments seem very slow to respond.
Just how close we may be to a nightmare climate change scenario was discussed yesterday at the annual UK Festival of Science, organised by the British Association for the Advancement of Science and taking place this year in Norwich.
The speakers described a grim future if collectively the world fails to act to counter runaway climate change. One speaker suggested we might have as little as 10 years before we reach an irreversible "tipping point" that would change the planet as we know it.
Antarctic ice cores have given us a canary in a coal mine-like warning about what human activity has done to the earth's atmosphere, stated British Antarctic Survey glaciologist, Dr Eric Wolff. "In particular, the air bubbles in ice cores act as tiny canisters of ancient air. By extracting them we can directly measure the concentration of gases such as carbon dioxide and methane in the past atmosphere."
Ice cores recovered from the Antarctic's "Dome C" provide climate information stretching back 800,000 years. They reveal the levels of climate-changing carbon dioxide and methane gases in our atmosphere and how the levels have changed.
Dr Wolff's recap on accumulated ice core data showed that for the past 8,000 centuries carbon dioxide levels varied between 180 and 300 parts per million (ppm) in air. It now stands at 380ppm, he said. The methane level was never higher than 750 parts per billion (ppb) but it now stands at 1,780ppb.
These aren't just numbers, he pointed out. Rises in carbon dioxide and methane have always been linked with rising world temperatures, research has shown.
The modern rate of change is also frightening. The fastest rate of carbon dioxide rise in all that time was 30ppm over 1,000 years. Yet that greenhouse gas has risen by 30ppm in the last 17 years.
"Ice cores have shown beyond doubt that humans have changed the composition of the atmosphere in the last 200 years," he said. Perhaps more importantly, the levels and rapid rate of change have put us outside the natural range of the last 800,000 years. "We are really in an experiment where we have no analogue for the result."
Our lives might be changed irreversibly by all this in as little as 10 years, according to special professor in sustainable energy at the University of Nottingham, Prof Peter Smith. Scientists believe we will reach a tipping point for self-sustaining global warming when atmospheric carbon dioxide levels reach 440ppm. This could be reached in 15 to 20 years, he said.
At that stage a wholesale meltdown of polar ice could push sea levels up by metres. "Governments could have only 10 years to determine the destiny of the planet," Prof Smith stated.
Governments must act to counter carbon dioxide release, largely through energy efficiency and use of renewable energy sources. "We really have got very little time. We have perhaps five years to do feasibility studies and five years to put things in place."
"The best resource we have got is the sea." Waves and tidal flows could provide huge amounts of power, he stated. "There is an enormous amount of power in the water."