Talk of global warming will fill the balmy air of Hawaii this week. President Bush will host representatives of 15 of the world’s biggest economies that lead the global pack on greenhouse emissions to discuss setting goals that can take over where the Kyoto Protocol leaves off in 2012.

However, Earth’s atmosphere isn’t exactly waiting in the wings. Change is already occuring, due to gases emitted over the past hundred years. A century is a long time – but what about what happens in the next five minutes:

— Burning oil, petrol and coal will throw about 300,000 tonnes of carbon dioxide into the air.

— Human-produced greenhouse gases will trap enough sunlight to power a 40-watt lightbulb for every 40 square metres on Earth.

— Two people will die from illnesses related to global warming.

The flip side of these ominous numbers is that personal and societal actions make a concrete difference here and now, not just in a hazy climatic future. Let’s say you replace an incandescent lightbulb with a compact fluorescent or, for your holiday, opt for a train to Nice instead of a flight to Cyprus.

Imagine a half-tonne of refuse strewn across a tropical ocean for a hundred years. Then imagine having it within your power to keep it from getting there. In the ocean of air in which we live and breathe, we have that power.

— Robert Henson is author of The Rough Guide to Climate Change, published today, £10.99

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