Kevin Drum sounds a little bit down in the mouth:
If you were teaching a graduate seminar in public policy and challenged your students to come up with the most difficult possible problem to solve, they’d come up with something very much like climate change. It’s slow-acting. It’s essentially invisible. It’s expensive to address. It has a huge number of very rich special interests arrayed against doing anything about it. It requires international action that pits rich countries against poor ones. And it has a lot of momentum: you have to take action now, before its effects are serious, because today’s greenhouse gases will cause climate change tomorrow no matter what we do in thirty years.
I have to confess that I find myself feeling the same way Andy does more and more often these days. It’s really hard to envision any way that we’re going to seriously cut back on greenhouse gas emissions until the effects of climate change become obvious, and by then it will be too late. I recognize how defeatist this is, and perhaps the proliferation of extreme weather events like Sandy will help turn the tide. But it hasn’t so far, and given the unlikelihood of large-scale global action on climate change, adaptation seems more appealing all the time. For the same reason, so does continued research into geoengineering as a last-resort backup plan.
I don’t think this is really quite the right way of thinking about the problem with it’s all-or-nothing, either-or quality. I’d like to suggest some other ways of framing the issue that are helpful to me in staying motivated to take action. As a starting point, let’s look at a few emissions scenarios and temperature projections:
These aren’t the latest and greatest, but the exact details don’t matter to understand the overall shape of the problem. The charts run from 1900 to 2100 – so the present is roughly in the middle. At the top are three paths for CO2 – growing from its pre-industrial value of about 280ppm through values up over 800ppm in the case of the A2 scenario, and stabilizing in the mid 500s by century end in the case of B1. Note that we are currently up to about 394ppm (seasonally adjusted) and still climbing fast.
You can imagine better scenarios, but bear with me a minute. The three scenarios above at least represent a huge range in how well humanity responds to the problem. If you now look at the resulting temperature projections in the lower panel, two things become evident: 1) there’s almost no difference at all in the temperature path in the next few decades based on emissions trajectory, and 2) by century end, it makes a really big difference in the total temperature change.
So, firstly, it seems to me that we have no choice at all but to do quite a bit of adaptation. There’s already been enough climate change to make a noticeable difference in the weather – bigger, nastier heat-waves and droughts, more precipitation extremes, etc. Given that we’ve got a bit less than a degree Celsius of temperature rise so far, we can be confident we are going to get at least another degree pretty much regardless of what we do. There seems very little doubt that that’s going to be enough to finish melting the north pole in summer, cause some pretty profound changes in northern hemisphere weather, greatly increase droughts and downpours, etc. Sea level is going to rise, and the rate of rise is going to accelerate.
So, coastal communities all over the world are going to have to look at what happened to New Orleans a few years back, or what just happened to Manhattan, and realize that the odds of those kinds of events are just going to get higher and higher as we steadily add more and more inches to the sea level and more degrees to the ocean surface temperature with the passing decades. No responsible community can afford not to plan for that and put in place the levees and sea walls and pumps and plans that are implied.
Similarly, farmers and agricultural suppliers and financiers are going to have to adapt to a world in which the weather is wilder and thus crop yields in any given location are less certain and more work needs to be done to bring forth the necessary total harvest to feed the world’s growing population. Some places are going to have to be abandoned, and others are going to have to be opened up to agriculture.
At the same time, it’s also very important to recognize that an end-of-the-century state of 2oC-and-stabilizing is going to be a completely different thing than 4oC-and-accelerating. The former is going to be bad, but the latter is going to be well on the way to hell:
- energy audits, insulation, limiting air infiltration, efficient windows.
- buying commercial renewable power.
- installing solar panels, or wind where applicable.
- replacing fossil fuel powered heating systems and water heaters with minsplit or geothermal heat pumps.
At the individual transportation level it’s about
- buying and using an electric vehicle, or a hybrid/plugin as an intermediate step, and/or
- locating in a place where it’s possible to walk/bike/public transport instead of driving
At the level of businesses it’s about
- buying commercial renewable power
- installing solar, etc, where applicable
- making facilities as energy-efficient as possible
- transitioning towards use of biofuels where there’s really no alternative to liquid fuels
- transitioning towards use of vido-conferencing to limit use of air travel.