Climate Change Already Damaging Global Economy

[GliderGuider]

13. Pacala and Socolow sound a little outdated today.

It's been 8 years since P&S published their wedge stabilization plan. Here's what SkepticalScience says about it:

PS04 examined what would be required to stabilize atmospheric carbon dioxide concentrations at 500 parts per million (ppm), which would require that GHG emissions be held near the present level of 7 billion tons of carbon per year (GtC/year) for the next 50 years.

PS04 used the concept of a "stabilization wedge", in which "a wedge represents an activity that reduces emissions to the atmosphere that starts at zero today and increases linearly until it accounts for 1 GtC/year of reduced carbon emissions in 50 years." Implementing seven such wedges would achieve sufficient GHG emissions reductions to stabilize atmospheric carbon dioxide at 500 ppm by 2050, and emissions would have to decrease linearly during the second half of the 21st century.

Aside from the fact that nothing whatsoever has been done to implement wedges in the last eight years, it's now accepted that the target has to be below 350 ppm, not 500. After all, we're seeing damage from climate change today at (barely) under 400 ppm. Achieving 500 ppm required a heroic effort starting 8 years ago, and since then we've added another 15 GtC to the atmosphere - over and above the 7 GtC/year they allowed (which was already far too much). We are falling further and further behind the curve.

Then there's the little matter that their (and Joe Romm's) wedges include nuclear power (700 GW plus 10 Yucca mountains...), either doubling vehicle fleet efficiency or cutting driving by 50% - world-wide, 2 million big wind turbines, coal with CCS, turning all global croplands into no-till...

Pacala and Socolow created an interesting paper exercise, but not something that was feasible. To try and sell this as a "solution" was naive in the extreme - even eight years ago when we were all gullible children who hadn't seen climate negotiations fall flat on their faces over and over and over.

Don't get me wrong, a lot of these suggestions make perfect sense - so long as we bound our expectations with global political realities. Some mitigation may be possible. We may manage to keep CO2 under 500 ppm rather than have it rise to 700 by the end of the century - but reversing the climate change that has already begun is not in the cards, at least not while keeping global industrial civilization in its present form.

There is one thing that will stop climate change from getting worse though, and over the long run would even reverse it. It's the only thing that has so far been proven to reduce CO2 emissions - a permanent global economic depression. That would do it, and it's probably even going to happen, but most people will likely think it's even worse than a carbon tax...