2011-10-28 11:24:34"Shut down the planet for 33 years to save one degree Fahrenheit"


I found this video today of the Viscount on Glenn Beck in October of 2009. He uses an argument I haven't seen directly rebutted anywhere, so I thought I'd bring it to everyone's attention. Here it is in a nutshell.

Global anthropogenic production of CO2 is 30bn tons per annum representing 2ppm of the atmosphere. The IPCC says in the next 100 years temps will rise 7 degrees F and CO2 will increase by 468ppm.[1] Taking the IPCC figures CO2 production will be 1 trillion tons per degree of warming. Therefore to save 1 degree F in temperature we have to cut 1 trillions tons of CO2.[2] i.e we have to completely shut down the planet for 33 years[3] just to save one degree.

[1] The gain of 468 ppm is because Monckton uses 836 ppm in 2100 from the A2 projection and subtracts 368 ppm in 2000. Discussion of shenanigans with the trend lines he fits to these points can be found here, but that's probably not relevant for this.

[2] 30Gt/y / 2ppm/y = 15Gt/ppm. And then, get this, 468 ppm * 15Gt/y/ppm = 7.02Tt. Finally, 7Tt / 7°F = 1Tt/°F

[3] 1000Gt / 30Gt/y = 33y

So off the top of my head, I can see a few problems here:

  • Obviously, we'll have to reduce our GHG output by a lot, that's the whole point. But no one is assuming we'll shut down the world for 33 years. This could just as easily be a 1/3 reduction for 100 years. But what IPCC proposes instead is a gradual, global reduction in emissions which by the end of the day will save a large amount. (Presumably even more than his mythical 33 years of emissions? "Area under a curve" questions bring back unpleasant memories of freshman year. :-)
  • He's assuming that yearly emissions will remain constant, when in fact they will increase in A2. Not sure if that matters in the end, but it's certainly not correct.
  • Sensitivity is defined in degrees Celsius for a doubling of CO2. Presumably this means that if we get 3° for 368 to 368*2=736, then for the next doubling (to 1472) each ppm is actually half as powerful. I know I'm skating dangerously close to a (relatively) common skeptic canard about CO2 not mattering because the more we emit, the less each molecule matters, but it feels like there's something wrong with his linear assumption here.

That's what I've got, and presumably it adds up to the whole equation being bunk. But I wanted to ask about it here, to see if I'm missing anything else, and also ask if this argument (such as it is) deserves a response. Not sure how popular it is, but I have see it in this video and now on several other fora while researching the video. So it _is_ (or at least was) being used by some people.

Your thoughts are appreciated.

2011-10-28 12:07:13
Dana Nuccitelli

Yeah, the linear assumption is wrong.  This is really dumb, because the IPCC already shows the temp change for various emissions scenarios, i.e. Scenario B1 is nearly 2°C less warming than Scenario A2 by 2100, and doesn't call for shutting down the global economy.  As I recall, Scenario B2 calls for 1.3 to 1.8 trillion tons of CO2 emissions by 2050.  Keeping the warming below 2°C, which is 2°C less than Scenario A2, requires limiting emissions to about 1 trillion tons of CO2 by 2050 (see my post on The Critical Decade).  Scenario A2 is about 2 trillion tons by 2050.  So it's actually only a 1 trillion ton reduction to cut 2°C.  And of course there are ways to achieve that reduction without shutting the economy down, because we're still allowed 1 trillion tons between 2000 and 2050.