BBC NEWS | Science/Nature | Warming ‘already changing world’
The Intergovernmental Panel on Climate Change (IPCC) report, due to be published today, will make the case that of 29,000 pieces of data on observed changes in physical and biological aspects of the natural world, 85% are consistent with a warming world.
I met some Americans recently who put forward the view that global warming was still an unproven phenomenum. They were not trying to advance a political agenda â€” it was just that this is what they understood to be the balance of scientific opinion.
Ten years ago, it was probably legitimate to say that the jury was still out on climate change â€” although the likelihood was far greater than that of an asteroid hitting the earth, which was something that NASA was actively investigating at the time. Five years ago you had to be fairly stubborn if you wanted to maintain the view that it wasn’t happening. As of today, it is, in many respects, the most likely thing in the world.
But, of course, there is still the 15% of data which does not directly support a global warming scenario. One could make a simple connection, and say that there is a 15% chance it won’t happen. Actually, that would be a false connection, because the cumulative effect of 24000 pieces of evidence gives a greater than 85% probability. ((As of February, the actual likelihood was put at 90%))
Ultimately, there cannot ever be cast-iron, 100% proof of global warming until the effects are so far progressed that it is far too late to do anything at all.
Nonetheless, reports on Radio 4’s World Tonight programme (5 April) indicated that there is already pressure from Washington, Beijing and Riyadh to tone down the levels of probability in the report.
Given the number of first-class minds available to advise these respective governments, it almost beggars belief that anybody could imagine that toning down the levels of probability changes anything. If it were any other kind of threat, these same governments would be clamouring to have it dealt with. Imagine that there was a breakout of a lethal pathogen, and it was given even a 25% chance of infecting a high proportion of the world’s population. Or imagine that Washington faced a 40% chance of a credible military attack. The aforementioned, miniscule, threat of a collision with an asteroid attracted millions of NASA dollars and led to the development of the Sentry programme.
In any risk management framework, even a probability of 10% for an event of catastrophic proportions would require extremely strong measures to be taken to reduce the likelihood and to mitigate the consequences.
Riyadh, Washington, Beijing: it’s time to stop bickering on climate change, because time is something we are fast running out of.