McKibben’s climate change math


Over the past few decades, Bill McKibben has been one of the more persuasive environmental writers chronicling the changes to our planet.  His recent article in Rolling Stone magazine continues his run.  The main point … we haven’t made much progress to address the serious threat of climate change:

“Since I wrote one of the first books for a general audience about global warming way back in 1989, and since I’ve spent the intervening decades working ineffectively to slow that warming, I can say with some confidence that we’re losing the fight, badly and quickly – losing it because, most of all, we remain in denial about the peril that human civilization is in.”

According to him, the forecast is not rosy and our collective will is not strong.

I’ve always appreciated his writing because he starts off with sound science and then tries to think through how it plays out in the very real game of politics, economics, and human nature that we all are engaged in.  I don’t always agree with everything he says, but he is able to make the science of global change a little more accessible to everyone.

In this article he concludes that the fossil fuel industry is blocking any progress that people are trying to make toward reducing our impact on the climate system.  His main argument rests on three numbers ….

  1. 2 degrees Celsius = The rise in global temperature we should stay below (we’ve seen about 0.8 degree rise so far).
  2. 565 Gigatons = The amount of carbon that can be added to the atmosphere to stay below a 2 degree rise.
  3. 2795 Gigatons = The amount of carbon stored in fossil fuel reserves is 2795 Gigatons (five times the amount in #2).

So, we are on a course to put five times the amount of carbon into the atmosphere than we should, if we want to keep the temperature of the planet from rising more than two degrees.

Of course, you could quibble with the numbers he selected (and a lot of people will), but when you look at them there is logic with the way that he chose them.  A two-degree rise doesn’t sound like a lot, but we’ve already seen big changes with less.  But he’s putting out an argument that we can talk about, based on numbers that you can check out for yourself, published somewhere among the heap of information we have amassed.

“If people come to understand the cold, mathematical truth – that the fossil-fuel industry is systematically undermining the planet’s physical systems – it might weaken it enough to matter politically.”

What we choose to do with the numbers is for us to discuss and decide.  It’s true that he often takes a gloomy approach to our situation on the planet.  But how would you rewrite the story and make it less so?