Wednesday, December 28, 2011

Let me count the ways



How can we as a society slow climate change?

Right now the discourse about solutions is limited by the problem that many of the stakeholders have refused to come to the table, instead denying the problem exists, or prioritizing other concerns.

Someone like me, designing a program more or less in a vacuum, is free to come up with what they view as a simple and an optimal approach. But when the action really starts, the program will likely not be optimal, and not be simple. That's OK: slowing climate change is a matter of survival, and like fighting a war, we do not need to find the optimal solution, just a solution that works.

It's easy to lose sight of that, I think. Creating a low-emissions society is likely to be an expensive and difficult undertaking, and when arguing for our own favorite approach, it is easy to slip into the mentality that says if this is not done in the best way (my way) that failure is assured.

+80m sea level -- not soon, but soon to be inevitable
If we embark on a messy, complicated, in some measures unrealistic approach; an approach that pampers some stakeholders and imposes an unfair burden on others, that will be inefficient, and in some measure unjust, but nowhere near as bad as doing nothing.


Progressives, environmentalists, conservatives, and libertarians are likely to have different opinions as to the best approach. We should celebrate the day when everyone is arguing about how to fight climate change, rather than arguing about whether it is happening. The wider the array of options, the more likely any given faction can find an approach they like. So what are some of the options?
From Nordhaus et al (2010)

Carbon taxes (higher or lower), cap and trade (fixed allowances versus falling quotas vs buy-back), regulation (industries must cut emissions by 5% per year, figuring out how themselves; energy efficient technologies mandated; high mileage standards for cars), direct intervention (by, for example, mass producing the new AP1000 reactor like Liberty ships, by the thousands. Or, for the more ambitious, we could quickly finalize and mass produce something such as a thorium-based molten salt reactor.) There is carbon sequestration, via tree planting or no-till agriculture or subterranean injection or transferring the carbon to the deep sea.

There are various methods of geoengineering: aerosol injection, painting roofs white, shooting a saltwater spray upwards to generate more reflective clouds.

We can subsidize research and development into low-carbon energy sources; we can undertake a variety of methods to improve energy efficiency (upgrading to a national HVDC grid, for example, or changing building regulations, or reducing traffic congestion with smart highways, or improving our rail networks.)

In terms of reaching an international accord, we can proceed with multilateral negotiations, like the ones that produced the Kyoto Protocol, or we could pursue a more muscular approach, like the recent EU ruling on commercial airline emissions; identify large countries ready to move forward and pressure others to cooperate with trade carrots and sticks.

I could go on. Some of these methods are better than the others; most would not work singly, meaning we need some combination of approaches. Geoengineering, for example, is not (in my opinion) practical by itself, chiefly because you would have to continue it for hundreds or thousands of years, and any interruption, such as an international conflict, could lead to extremely rapid warming. We might, however, decide to gradually reduce our emissions over the next century, using geoengineering for a couple of centuries to avoid tipping points, and ramping up carbon sequestration to have CO2 back at a reasonable level by then.

We have to do something, and soon. The harmful effects of global warming continue to arrive ahead of schedule (h/t Steve Bloom.)

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