Extinction Events and 100 Generations of Carbon

Posted on March 24, 2013


Triassic Extinction

Graphic from Universe Review

Carbon Karma Is Karma on Steroids

Let’s put two ideas together to show some of the dimension of things, a taste of the real cost of carbon.  Joe Romm’s headline practically covers the first idea by itself, “Doubling of CO2 Levels in End-Triassic Extinction Killed Off Three Quarters of Land and Sea Species.”  Romm’s article discusses a new study in the journal Science clearly connecting the End-Triassic Extinction event with a massive infusion of carbon dioxide into the atmosphere and the oceans.

We’re on track presently to doubling or more than doubling the CO2 levels in Earth’s atmosphere as compared to pre-industrial times.  So what will our present-era, human-caused extinction look like if what happened 200 million years ago happens to our children and grandchildren?

That by itself should give us pause.  Do we really want to be the generation responsible for a mass extinction event?  It’s a genuine possibility.  Some people say our civilization is already undergoing such an event, given that our current rate of extinctions is already an order of magnitude greater than the background rate.

But 75%?

No more lions and tigers and bears, oh my!

The second idea has to do with how long our legacy will last, that is, how long will it take for this climate (and chemical) disaster to play out?  Well, extinctions are forever, so that part (Jurassic Park fantasies aside) we could never realistically undo if we allow it to happen.  The course of a few million years will give us back some new species, not quite the same as the ones we have now, but millions of years have nothing to do with the human timescale.  Millions of years equals forever.  On the other hand, the carbon we are presently pumping into the atmosphere with every drive to the store and every commute to work in our suvs will–eventually–cycle back into stability.  It just takes time.  50 to 100 human generations of time. That’s how long it takes for the effects of carbon pollution to go away.

Okay, it’s a human timescale but not a very reassuring one.

Aboriginal culture says that we should look at the effects of our actions for the seven generations following.  That’s good enough for most things, but not good enough for carbon, according to scientists.  Seven times seven generations is what we’re looking at for CO2, and that’s just the optimistic end of the estimate.

Two ideas.  Two ways of looking at the problem we’ve got.  Neither of them easy on the conscience.

But a really good way to put your commute in perspective.  If fifty to a hundred generations of people are going to be feeling the effects of that drive to the store, and all eternity is going to be cursing us for wiping out species and incidentally turning the oceans acid, then carbon karma is karma on steroids.  Walking shoes and buses have never looked so noble.

And instituting a carbon tax could get you sainted.