“ I am prepared to take risks – whenever I board an aeroplane for example. Are risks from the climate more immediate ?
Professor Rajendra Pachauri puts it starkly: “If there is no action before 2012, that’s too late.What we do in the next two or three years will determine our future. This is the defining moment.” First let’s look at what might happen if temperatures exceed 2 degrees Celsius, the broadly accepted danger zone.
The UK Meteorological Office warns that a rise above 2 degrees Celsius will cause havoc, with up to two-thirds of the world affected by water scarcity, major losses in agricultural productivity (grain reserves are already at a record low) and the loss of many ecosystems. With a 3 degrees celsius rise the Amazon rainforest would collapse and most coral reefs would almost certainly die, the oceans would become more acidic and less able to absorb carbon dioxide. The knock-on effects from these changes are unimaginable. And if runaway warming kicks in after a tipping point is reached we can kiss goodbye to civilisation. It’s that serious.
Stern said that concentrations were 430pm CO2e by extracting carbon dioxide from the atmosphere, Stern’s diagram shows there is a five per cent chance that temperatures would increase by almost 3 degrees celsius above pre-industrial levels. In the light of the awful effects outlined above it is appropriate to ask: would you board an aeroplane if you knew it had a five per cent chance of crashing?
At 450ppmCo2e the Stern Review gives a 50 per cent chance that temperatures will reach 2 degrees Celsius above pre-industrial levels, and a five per cent chance that they will climb to 3.8 degrees Celsius. At 550pmCO2e, the target adopted by the Review, the diagram shows a 50 per cent chance that temperatures will reach 3 degrees celsius and a five per cent chance that they could soar to 4.7 degrees Celsius above pre-industrial levels.
Sir Nicholas Stern is an environmental economist. his discipline requires him to assume that our economy is sacrosanct and to explore what it can afford to spend on environmental issues.
Ecological economists invert the question. They see the human economy as just one component within the planet’s ecology and ask what limits are imposed on economic activity by the environment. They say that you cannot extrapolate from past events because natural systems frequently tip from one stable state into another. We already over-exploit the world’s resources, and all our efforts should now go into repairing the damage and learning to live within the Earth’s systems before it is too late. ”
Alastair Sawday (2008: 12-14) What About China?