2005 pandemic made leaders consider all scenarios. The same must apply for global warming, argues Sir David King
By Alex Pashley
The spectre of “society collapsing” as humans caught a deadly strain of avian flu forced the UK government to stockpile vaccines in 2005, according to Sir David King, the UK’s top climate envoy.
The odds were not dissimilar to the planet cooking by up to a cataclysmic 7C from next century – less than 1% – but the risk was deemed worthwhile of intervention.
Policymakers must display the same fervour in their long-term assessment of the risks of climate change, said King at the launch of an independent report on Monday.
Greenhouse gas emissions are set to keep rising for the next few decades before levelling off or decreasing gradually, in spite of voluntary carbon cuts by countries, according to the study carried out by researchers in the UK, US, China and India.
That puts a warming planet on multiple trajectories, where melting ice sheets and chronic droughts make plausible a range of disastrous scenarios for civilisation.
“There seems to be a much less deliberate consideration of worst-case scenarios when it comes to long term climate change,” King, an eminent scientist and lead author, told an audience at the London Stock Exchange on Monday.
“It may have something to do with the post-Copenhagen success of the climate denial community and the worry that people shouldn’t be scaremongering.
“What of course one does in a risk analysis is nothing to do with scaremongering – it’s looking at probability against big outcomes.”
The UN’s climate science panel, the IPCC forecast multiple trajectories for global warming over the course of the century. If emissions continue at current rates, the planet could warm by as much as 5C, a level scientists say is catastrophic.
Even starker scenarios are possible, and aren’t being fully considered, warned the report. A UK government minister, Baroness Anelay drew parallels between the importance of tackling climate change with nuclear proliferation at the event.
The IPCC latest assessment report made just one mention of warming of 5-10C out of 67 occasions. The level of 2C – and internationally agreed goal – received 31 mentions, with 4C, 26.
A global temperature rise of 4-5C would see crop yields drastically reduced, such as maize in the Midwestern US and rice in southern China.
Meanwhile, 1m of global sea level rise could increase the likelihood of what is now a ‘100 year flood event’ 200 times more likely in New York, and 1000 times more likely in Kolkata.
If governments want to avoid this, “start from an understanding of what it is that we wish to avoid; then assess its likelihood,” recommended the report.
Already populations are experiencing climate impacts, given governments evidence for action.
A growing body of evidence links the Arab Spring with a 2011 Russian heatwave that lowered wheat yields, pushing up bread prices across North Africa and the Middle East. Drought in Syria between 2007-11 could have ignited the country’s conflict.
So far, global temperatures have risen about 0.85C on pre-industrial levels. Resource conflict would sure intensify in a warmer planet.
Leaders should use the same probabilities for companies going insolvent, 1 in 200, said Trevor Maynard, head of exposure, risk and reinsurance at the leading insurers, Lloyds of London.
Real Admiral Neil Morisetti, former UK special representative for climate change, described climate change in terms of a “security threat”, as trade routes were disrupted and terrorism prospered in destabilised regions.
Military strategy, seen in the US quadrennial defence review reflected on the “middle ground of the risk profile, the most likely or best option because that fits neatly with the allocation of resources,” he said.
“The reality is we need to look at the tails of that risk profile.”