Richard Betts Puts the Frighteners on Eli

As somebunnies may or may not be aware, Emma Thompson had some things to say about the threat of the changing climate a few days ago.  In talking about Shell's drilling and particularly their drilling in the Arctic:

They continue without cessation, to extract and they continue their plans to drill in the Arctic. They have plans to drill until 2030 and if they take out of the earth all the oil they want to take out, you look at the science, our temperature will run 4 degrees Celcius by 2030 and that is not sustainable.

This lit Richard Bett's torch.  Betts was inflamed with this "non scientific" claim and Prof. Betts took to the twitter.  Eli trusts the smart readers here can find the tweets, but what this post is about is one of the first

.@BBCNewsnight Your guest Emma Thomson is *wrong* to claim science says 4C by 2030. Earliest credible estimate 2060s http://t.co/XgmNrBSO7h

— Richard Betts (@richardabetts) September 3, 2015

Now Eli is not going to get involved about whether ET was talking about a committed rise to 4C by 2030, or an actual rise, of what the people she talked with were talking about.  Gavin pretty much summed that part up

When scientists focus public outreach on correcting technical errors instead of big picture values, they reinforce 'scientization' of debate

— Gavin Schmidt (@ClimateOfGavin) September 4, 2015

and Eli had a few things to say along that line.  Eli and Gavin were not pleased by Richard Betts' tweeting, and perhaps in response, he posted some remarks on Facebook September 4:

If global greenhouse gas emissions do not begin to decline in the next few years, the chances are that global warming will exceed the 2°C “guardrail” that the EU and UN aim to stay below. HELIX is researching the impacts of higher warming levels, specifically 4°C and 6°C. What would a 4°C or 6°C world look like, and when could these be reached?

If the world does warm by 4°C, this can be expected to have profound implications. Previous research shows that some areas could get a lot drier, while others a lot wetter. Many places will warm by more than 4°C, and indeed we’d expect more of the major heatwaves such as that which caused many deaths in India this summer. Also of course we’d be locked in to ongoing sea level rise due to melting ice and swelling of warming ocean waters.

Emissions are growing along a high pathway, as high or higher than the ones Betts and co-authors considered

For a scenario of high GHG emissions, the earliest time of reaching 4°C above pre-industrial was around 2070, and the latest sometime after 2100. In the most extreme case, 6°C is projected by 2100 although most models do not show this. If feedbacks are stronger or weaker than in those simulations, the timing could be outside these bounds – but evidence for these would need careful examination before we could be confident in this.

Richard Betts worries that Emma Thompson is crying wolf.  Eli would point out Richard Alley's remarks on such

You have now had a discussion or a debate here between people who are giving you the blue one and people giving you the green one. This is certainly not both sides. If you want both sides, we would have to have somebody in here screaming a conniption fit on the red end, because you are hearing a very optimistic side

Strangely though he is most concerned about premature concern with climate disasters to be

Secondly, if people come to believe that catastrophic impacts are only round the corner, this could lead to wrong decisions made in panic. A lot is being done to make us more resilient to the climate change we’ve already set in motion – new flood defences, plans for reservoirs and water supplies, and so on. But these are expensive, and doing these too early could cost billions. And if people are scared into moving away from their homelands because they think it will be uninhabitable, this would only add to the existing refugee crisis, for no good reason.

This is absolute and dangerous nonsense.  The people who are going to be pushed out of their homes by climate change are almost all very poor, and are not going to start moving until they start dying.

POSTSCRIPT:  Anybunny who thinks they can move a billion or more people in a few decades is sipping some interesting stuff (AIN'T GONNA HAPPEN

The deadly temperature rise is going to be a committed temperature rise decades before they reach full effect. The most likely scenario are hot summers in the Ganges and Indus valleys which reach or approach the wet bulb temperature limit for survival.  This is already close to happening.

Sherwood and Huber who were the first to write on the wet bulb temperature limit wrt climate change said

We conclude that a global-mean warming of roughly 7 °C would create small zones where metabolic heat dissipation would for the first time become impossible, calling into question their suitability for human habitation. A warming of 11–12 °C would expand these zones to encompass most of today’s human population. This likely overestimates what could practically be tolerated:

One of the bunnies back in 2010 added

It's the creeping statistical hints between the lines of this paper that really bother me. Long before or even if we never see broad areas permanently enter a existentially threatening torrid regime, what about excursions? For instance, Pakistan this year has seen record temperatures approaching 54 degrees C in places where many people live, fortunately with lower humidity and only for handful of days but what about when/if such aberrations extend to a handful of weeks and are accompanied by inexorably increasing humidity? The resulting disaster would cause migrations. The worst-case scenario in Sherwood and Huber would not have to happen before we effectively lose major swathes of territory for year-round habitability.

What is scary is that Richard Betts thinks that 4 C by 2060 is possible, and by ~2100 inevitable on current emissions.  We are now 1 C from pre-industrial.  Richard Betts thinks we are going to triple that in 85 years.  There is a chance the globe will warm to 6 C by then.  Richard Betts says stay calm and carry on.  That is not very good advice.

Among the things that Thompson has said is that she would rather die than see another Spiderman movie.  Kumbaiya my bunnies Kumbaiya