The stated objective of the United Nations Framework Convention on Climate Change is to achieve “stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.” The most problematic aspect of this mandate is the open definition of ‘dangerous anthropogenic interference.’ Given that we have direct ice core evidence that concentrations of carbon dioxide are higher than at any point in the past 650,000 years – along with indirect evidence that this is the peak for the last 20 million years – it is fair to say that we are already interfering dangerously with the climate system.
Of course, one cannot go straight from showing elevated CO2 to ascribing danger. That said, the link between greenhouse gasses and increases in radiative forcing and temperature is incontrovertible. So too, the realities of icecap and glacier melting and ocean acidification. The question is no longer about whether or not we will cause dangerous interference, but how much danger we are willing to tolerate in exchange for less rapid and comprehensive changes to our high-carbon lifestyles.
The only difference between anthropological interference in nature and nature doing its own thing is we think we have some say over what we do.
“, the link between greenhouse gasses and increases in radiative forcing and temperature is incontrovertible. So too, the realities of icecap and glacier melting and ocean acidification. The question is no longer about whether or not we will cause dangerous interference, but how much danger we are willing to tolerate in exchange for lesser obligations to change our lives.”
If that’s true, then to the extent the “damage” has already occured, it is a natural phenomenon. The only thing that is “human” is what we can control.
One implication of this is that the past has no moral standing whatsoever. It is no more useful to debate whether Napoleon was doing right by some action, as to debate the moral standing of the actions of others in abstraction of any effect you can have on them. The only thing that has any “humanity” to it, is what we actually do. That’s the extent to which the world is spontaeneous for us.
Tristan,
One reasonable analogy is between climate change and drinking large amounts of vodka. The way our bodies respond is ‘natural’ but the choice to keep drinking is anthropogenic interference.
We are now akin to someone on their tenth or eleventh shot. We are seeing significant effects, including the reality that there will be sudden and catastrophic effects eventually.
I wasn’t saying anything explicitly about morality in the post above. I am just saying that the debate about where ‘dangerous’ interference will begin is misleading. Dangerous interference has already begun.
James Hansen has apparently called the European Union’s 450ppm stabilization target “a guaranteed disaster” which would cause all of Greenland and Antarctica to melt, raiding sea levels by 75 metres.
He thinks that the United States needs to completely halt emissions from coal by 2030, with an immediate moratorium on building new coal plants.
“Last week the Alliance of Small Island States called for global warming to be limited to 1.5ºC over pre-industrial levels, something which many other poor countries support. Most richer countries, by contrast, are working on the basis of a limit of 2ºC. This seems one of the easier issues to resolve as many studies relating emissions to temperature agree that limiting a rise to 1.5ºC is in all practical ways impossible.
Some of the poorer countries appear to be using the 1.5ºC figure as a useful bargaining position from which to press for bigger emissions cuts from the rich world. The cuts proposed so far, although larger than might have been expected a year ago, are unlikely to limit global warming even to 2ºC. In addition, many poorer countries are seeking to extract more money from rich ones. A “fast start” package of $10 billion a year, over the next few years, which is being put together by rich countries is seen as grossly insufficient by poor-country negotiators, who talk of transfers of “5% of GDP”. On all this the new slimline text which is supposed to frame an agreement to replace the Kyoto protocol is magnificently reticent: “To be elaborated: a long-term goal for financing.””
‘Paltry’ Copenhagen carbon pledges point to 3C world
By Richard Black
Environment correspondent, BBC News
Pledges made at December’s UN summit in Copenhagen are unlikely to keep global warming below 2C, a study concludes.
Writing in the journal Nature, analysts at the Potsdam Institute for Climate Impacts Research in Germany say a rise of at least 3C by 2100 is likely.
The team also says many countries, including EU members and China, have pledged slower carbon curbs than they have been achieving anyway.
They say a new global deal is needed if deeper cuts are to materialise.
“There’s a big mismatch between the ambitious goal, which is 2C… and the emissions reductions,” said Potsdam’s Malte Meinshausen.
“The pledged emissions reductions are in most cases very unambitious,” he told BBC News.
In their Nature article, the team uses stronger language, describing the pledges as “paltry”.
“The prospects for limiting global warming to 2C – or even to 1.5C, as more than 100 nations demand – are in dire peril,” they conclude.
Between now and 2020, global emissions are likely to rise by 10-20%, they calculate, and the chances of passing 3C by 2100 are greater than 50%.
Projections of when temperature change will exceed 2 °C above pre-industrial levels
Manoj Joshi, Ed Hawkins, Rowan Sutton, Jason Lowe & David Frame
Nature Climate Change 1, 407–412 (2011) doi:10.1038/nclimate1261
Published online 23 October 2011
Climate change projections are usually presented as ‘snapshots’ of change at a particular time in the future. Instead, we consider the key question ‘when will specific temperature thresholds be exceeded?’ Framing the question as ‘when might something happen (either permanently or temporarily)?’ rather than ‘what might happen?’ demonstrates that lowering future emissions will delay the crossing of temperature thresholds and buy valuable time for planning adaptation. For example, in higher greenhouse-gas emission scenarios, a global average 2 °C warming threshold is likely to be crossed by 2060, whereas in a lower emissions scenario, the crossing of this threshold is delayed by up to several decades. On regional scales, however, the 2 °C threshold will probably be exceeded over large parts of Eurasia, North Africa and Canada by 2040 if emissions continue to increase — well within the lifetime of many people living now.