Is it too late to prevent dangerous climate change?

A lot of people think it is too late to prevent dangerous warming. That we have already passed the point of no return in regard to limiting the increase in global mean surface temperature to 2°C above that of pre-industrial times. Some people think that we'll be lucky to stay within 4°C of warming this century. Anthony Watts doesn't think we've passed the point of no return. He wrote about how Dr Pauchari said, back in 2007, that "If there's no action before 2012, that's too late. What we do in the next two to three years will determine our future. This is the defining moment." Anthony called it a failed prediction (archived here).

What makes Anthony think that Dr Pauchari was wrong? What makes him think that it's not too late? He doesn't say. All he says is:

Well, it’s now August 2015, the world isn’t destroyed and no new U.N. climate treaty has been presented, though there’s a lot of hullaballo ramping up for the Paris COP21 meeting this coming December. 

So it's another case of the usual brain failure you so often see in deniers, that if something hasn't happened yet then it never will happen. Notice that he also seems to assume that because the agreement to be made in Paris at the end of this year, hasn't yet been "presented" yet, that this means that global warming isn't happening - or something like that. He's a bit of a nutter, isn't he. Clear thinking eludes him. And remember, Anthony has called predictions "failed" even when they are for well into the future. Has he deluded himself into believing he has a time machine?

Looking at the carbon budget, we've already spent an awful lot. It would take a huge effort to stop emitting carbon soon enough to stay below the amount required. In January, Christophe McGlade and Paul Ekins had a paper in Nature, that stated that "globally, a third of oil reserves, half of gas reserves and over 80 per cent of current coal reserves should remain unused from 2010 to 2050 in order to meet the target of 2 °C. " That's a big ask, given the paltry efforts to shift to renewables so far.

Last year, Todd Sanford, Peter C Frumhoff, Amy Luers and Jay Gulledge wrote a commentary in Nature Climate Change, saying that:

It is time to acknowledge that global average temperatures are likely to rise above the 2°C policy target and consider how that deeply troubling prospect should affect priorities for communicating and managing the risks of a dangerously warming climate.

Many experts agree that Western Antarctica is past the point of no return when it comes to melting the ice sheets. The speed with which it happens is the only unknown. It could be sooner, like within coming decades or it could be later. It seems fairly certain that over the next few centuries, seas will rise by metres, not centimetres. And sea level could rise by anything up to two metres this century even.

Now the fact that it's too late to prevent 2°C of warming doesn't mean we shouldn't try. If we don't act, then we won't stop 3°C or 4°C or 6°C or more.

References and further reading

McGlade, Christophe, and Paul Ekins. "The geographical distribution of fossil fuels unused when limiting global warming to 2 [deg] C." Nature 517, no. 7533 (2015): 187-190. doi:10.1038/nature14016 (pdf here)

Sanford, Todd, Peter C. Frumhoff, Amy Luers, and Jay Gulledge. "The climate policy narrative for a dangerously warming world." Nature Climate Change 4, no. 3 (2014): 164-166. DOI: 10.1038/nclimate2148 (access courtesy Nat Geo)

The awful truth about climate change no one wants to admit - David Roberts at Vox. May 2015

Alarming UN report on climate change too rosy, many say -  Elisabeth Rosenthal and James Kanter in the New York Times, November 2007


From the HotWhopper Archives

• Anthony Watts, the seer, goes time traveling to 2041 and beyond - May 2015
• Unstoppable meltdown in Antarctica - and at WUWT, with a doozy of chart - May 2014