Many scientists and activists have stated, with good reason, that the 2007 IPCC 4th Assessment Report (4AR) didn’t look deeply enough into the potential costs of doing nothing to change the globe’s GHG emissions. The good news is that in addition to developing a more robust research methodology to dig into the unknowns of the science surrounding climate change, work has also taken place to assign realistic figures of the costs of adapting to climate change. The figures available for the past few years were viewed as having major shortcomings: unrealistic assumptions, not accounting for enough of the effects (which have interdependencies and feedbacks of their own), etc.
A new study was issued earlier this month by the International Institute for Environment and Development (IIED) that worked to address some of those concerns. For reference, I’m going to discuss the Section 8 material. It is not without its own set of caveats and disadvantages: it looks at the IPCC A2 scenario, for instance, even though our actual emissions have already outpaced this mid-range emissions scenario. There’s another equally out-dated caveat that I’ll talk about more below. So, take the results with a grain of salt – realize that these costs continue to be an underestimate of what we’re likely to face!
With that in mind, what are some of the results of this study? Without adaptation, the mean net present value of climate change impacts under the A2 scenario is $1240 Trillion.
That’s in 2000 US $, without any efforts towards adaptation. I can’t even fathom numbers that large. Nobody can. It’s an incredibly large amount of money. Annually by 2060, the mean costs run at $1.5 Trillion. That’s per year! Of course, since this scenario is already being quickly outpaced, perhaps the outlier costs in this report should be scrutinized. They run up to $20 Trillion per year! For the record, the 95% impact cost without adaptation is $3290 Trillion.
Okay, you might say, but you qualified these numbers by pointing out there were no adaptation measures taken. Right you are. So what do the impact costs look like with adaptation? Only $890 Trillion – a full $350 Trillion less. Under an IPCC scenario that is much rosier that the path we’re actually on.
These numbers offer a compelling counter-argument to those who say we can’t afford to act, that economies will crumble. No they won’t. Many climate mitigation strategies offer cost savings (more on this in a future post). Indeed, this study provides another useful look at how much money can be saved by acting like adults. In what they term the “aggressive abatement” case, that same mean impact cost of climate change impacts totals up to only $410 Trillion, without adaptation. By implementing adaptation strategies, the costs total up to $275 Trillion. The numbers get better and better with abatement and adaptation!
That pesky little caveat that I left hanging at the beginning comes back into play here. What does the IIED consider “aggressive abatement”? Setting 450ppm CO2 concentration as a goal. This comes despite the fact that climate scientists have presented a much lower concentration goal since the 4AR was issues: 350ppm. Now, let’s be honest. It’s clear from their analysis that stabilizing at 450ppm reduces impact costs by $615 to $830 Trillion by 2100. The cost to get to 450ppm? About $110 Trillion. That’s a 6-to-1 savings – certainly nothing that should be passed up.
So while the magnitude of the numbers are certainly daunting, their overall message is clear. Doing nothing to address climate change will likely cost upwards of $1000 Trillion. That kind of number is what will wreck economies – if governments could survive the accompanying social upheaval, an entirely different question. Implementing aggressive abatement strategies would cost $100 Trillion, reducing the impact costs to $300 Trillion. Doing so not only makes basic economic sense, but it might be the only thing that saves ecosystems and governments from collapse.
I said it after the House voted on the ACES bill: Rep. Markey voted to take us down the path of abatement and adaptation while Rep. Salazar did not. Rep. Salazar took what he considered to be the politically expedient path by voting against the bill, but in reality voted against his party, his country and his planet.
Sens. Udall and Bennet are likely to have their chance to “wow” us by working hard to help put together an aggressive climate bill in the Senate, vote for it, then vote to send something meaningful to President Obama. Or they can work to boost the dirty energy industries’ profits and doom this planet to intense droughts, acidified oceans and collapsing ecosystems and government. Pretty simple choice, don’t you think?
Cross-posted at SquareState.