Target Atmospheric CO2: Where Should Humanity Aim?

You may have already heard tell of this, a rather astonishing scientific paper by Jim Hansen and his team, but chances are that you haven’t read it, or even skimmed it. So consider this to be another chance, one you shouldn’t pass up. This, after all, is a paper that says that we need a “phase-out over the next 20-25 years of coal use that does not capture CO2,” and if there has been more easily understandable call for an emergency energy transition, we haven’t heard it.

Here’s a bit of the paper’s conclusion, from Yale Global Online, written by Hansen himself:

Our conclusion is that, if humanity wishes to preserve a planet similar to the one on which civilization developed and to which life on Earth is adapted, CO2 must be reduced from its present 385 ppm (parts per million) to, at most, 350 ppm. We find that peak CO2 can be kept to about 425 ppm, with large estimates for oil and gas reserves, if coal use is phased out by 2030 (except where CO2 is captured and sequestered) and unconventional fossil fuels are not tapped substantially. Peak CO2 can be kept close to 400 ppm, if actual reserves are closer to those estimated by “peakists,” who believe that the globe is already at peak global oil production, having extracted about half of readily extractable oil resources.

This lower 400 ppm peak can be ensured, assuming phase-out of coal emissions by 2030, if a practical limit on reserves is achieved by means of actions that prevent fossil-fuel extraction from public lands, off-shore regions under government control, environmentally pristine regions and extreme environments. The concerned public can influence this matter, but time is short, the industry voice is strong and climate effects have not yet become so obvious to the public as to overwhelm the disinformation from industry moguls.

“Industry moguls.” Nice words to hear from a scientist, eh