This blog has been silent for two years. Back then, I tried to maintain an overly ambitious posting schedule. When the usual academic responsibilities caught up with me, I was not able to continue writing. For a long time, I also felt I had very little to add to the present discussion. To my great surprise, however, I still receive emails about the blog, with people telling me how useful they found some of the posts on the blog. Add to this a lot of reading and thinking during the last two years, and I’ve decided to give the blog another try. This time, though, I’ll post less frequently!

My first comment is on an excellent and widely read recent piece by Bill McKibben on Global Warming’s Terrifying New Math. The most important part of the piece concerns the relationship between the goal of limiting the increase in the global mean temperature during the 21st century to 2C during the and the already proven deposits of fossil fuels. Meeting the 2C target with the unambitious 80% percent probability requires limiting carbon dioxide emissions to 565 new gigatons by 2050. This is scary when the proven deposits of fossil fuels add up to 2,795 gigatons — approximately five times the 565 new gigatons we have left.

Even if one accepts that the 2C target is by now hopeless, the mismatch between how much fossil fuel there is and what is needed to prevent potentially disastrous climate change is sobering. Given the recent technological revolution in the extraction of oil and natural gas, the real amount of carbon contained in available fossil fuels is probably much higher. Environmentally benign energy scenarios that seemed at least somewhat plausible only a few years ago, such as increased scarcity of fossil fuels, now lack credibility. Fossil fuels are abundant. They will be used unless policies and activism limit their use or technological progress renders them unable to compete with renewable energy.

McKibben is correct to note that there is no way to reconcile climate sustainability and the profitability of the fossil fuel industry. Any meaningful strategy to limit climate change is going to deprive the fossil fuel industry of readily available profits. This may result in increasingly radical climate activism, especially if our current political “leaders” continue to impress us with their ability to not lead.