RJ: I would suspect that certainly 2 degrees will result in sea-level rise to flood islands, [although]I don’t remember the elevation of the Marshall Islands. [In any event,] we have to think about the timescale. Will it flood those islands by 2050 or 2100, or are we talking about 2200 or 2300? The consequences, the full effects of the warming for ice melt, go on for many centuries after the atmosphere is stabilized, and the atmosphere is not yet in equilibrium.
The timescale of ice melt and sea-level rise is much longer than the timescale of the atmosphere coming into equilibrium with CO2. You can think of Greenland or Antarctica as being like a giant ice cube. If you place an ice cube out on the desk it doesn’t [immediately dissolve]; it takes a long time to melt. The ice on Earth is exactly that way and, moreover, the water in the oceans is away from the surface for centuries in some places. It takes a long time for all of that to come into equilibrium once we’ve stabilized CO2.
JF: Do you think that global carbon emissions will peak in the near future, or did we already witness peak emissions in 2014?
RJ: I don’t think we’ve hit peak emissions yet. We have countries like India that are still developing rapidly and whose per capita emissions are well below ours in the United States. We have encouraging signs in the European Union of a long-term decline in emissions. We have modest declines in the United States. We have China peaking in emissions within the next 5 to 10 years with only modest increases between now and then. It is the rest of the developing world, such as India, that will determine when emissions peak, but we have a lot of work to do to lower our emissions in the United States during that interval. I’m not thrusting [the entire burden]on [developing]countries like India.
JF: Can you give me some figures on the rise of renewable energy sources? Do you think that we’re making progress towards a post-fossil fuel economy?
RJ: The rise in renewables is meteoric — much faster than anyone expected. Pricing is playing a big part in that, as are policies as well. Prices have dropped much faster than anyone expected. Prices for solar panels, for instance, [have decreased substantially]. I think we’ll see a long-term role for natural gas (long-term being many decades), but eventually I am optimistic that we can have a primarily renewables-based economy [using natural gas as a stepping stone to an entirely renewable-based economy, which]is what is already happening. It depends on the timescale. [Does one define a] gradual transition as 25 years, 50 years, or 150 years? Natural gas is better than coal in terms of greenhouse gas emissions, but it is still a greenhouse gas.
JF: What are the prospects for negative emissions?
RJ: The 1.5 degree target (stipulated to in the Paris climate agreement) is almost upon us. Another decade or so of today’s emissions will use up the rest of the cumulative atmospheric budget for carbon dioxide, and we have infrastructure on the ground with life spans of 30, 40, and 50 years — we don’t typically walk away from those types of investments. That means that the 1.5 degree target is almost impossible without negative emissions.
Negative emissions, in principle, are a great idea. They allow us to remove carbon dioxide from the atmosphere. However, there are expensive. You are talking about trillions of dollars in investment, if you are going to remove billions of tons of carbon dioxide from the atmosphere year after year. Many of the technologies, even the simplest ones, like the combination of biomass energy and carbon capture and storage, are unproven at scale. We are just seeing pilot and modest-size facilities built today to do that. Industrial processes, like direct air capture, that remove CO2 from the atmosphere are feasible, but much more expensive than other options, and it is not clear that they can scale to billions of tons a year. People have proposed increasing or enhancing weathering. Imagine digging up minerals, reacting those minerals with carbon dioxide, and then burying those minerals in the ground again. In principle, that is what happens naturally — that’s a geologic process — but we are talking about doing in decades what the Earth does in thousands to millions of years, and doing it at the billion-ton scale.
I am skeptical that we can do it at sufficient scale to make a dent in emissions. People have proposed fertilizing the oceans to store carbon deep in ocean water and ocean sediments. Then there are older approaches like afforestation — planting trees where they weren’t before. Those things are definitely feasible, but at some point, you can only stuff so many molecules of carbon on land. The technologies are feasible, but they aren’t proven economically.
JF: How can Obama circumvent the gridlock in Congress to implement meaningful environmental policy? What are the prospects for a U.S. cap and trade or carbon tax system? Would these policies be effective in getting the U.S. to meet its climate goals?
RJ: Most people and most companies are already planning for a carbon price. We are not close to passing a national carbon tax or cap and trade bill. That won’t happen any time soon. States are already doing it, regions are doing it, provinces of Canada are doing it, the European Union has already done it. At some point, it doesn’t matter all that much whether the federal government passes a unifying cap and trade program or carbon tax. That would be better, but the world is moving [ahead]whether the national government acts or not. As for Obama’s ability to implement climate policy, there is not much more that he can do in 8 to 10 months. Implementing something like the puts us a long way towards our determined contribution for Paris. However, it’s not enough. We may be able to get there without it through initiatives in energy efficiency and increased renewables.
There are other policy levers that we can use to promote renewables that don’t require a price on carbon, but a price on carbon is a better market tool than didactic policies that mandate a certain amount of a certain technology. This is not the way most people want the economy to work. But one way or another, we’ll bring emissions down. We have CAFE standards for automobiles. We have renewable-fuel standards for bio-fuels. We have renewable portfolio and renewable electricity standards that states pass that have different mix of renewables requirements. All of that is happening. In my conversations with people in the business world, [my understanding]is that they would prefer a national policy. Then they wouldn’t have to navigate a mosaic of policies in different states and regions of the U.S. and North America. For that reason alone, I think we’ll eventually have such a policy. Oil and gas companies are already factoring in a future price on carbon when they make investment decisions. This is publicly known.
JF: What makes the Paris talks different from the Kyoto Protocols?
RJ: Paris is different because of a sense of shared purpose and because of the flexibility that the Paris agreement provides countries. It is a softer agreement than Kyoto tried to be, calling for contributions not commitments for a reason. I think the shared agreement is worth celebrating.
JF: How are verification systems for the carbon emissions of developing nations such as China and India different than those of the United States as stipulated in the agreement? Do you think that these weaker verification systems will enable China and India to under-report their emissions?
RJ: I am optimistic that, within the time-scale of this agreement, we can work out the verification that we need to. Will we be able to track every person, every car, every power plant? Probably not, but I don’t think we need to do that. We need to keep track of the big things. We have atmospheric and satellite-based tools that are getting better and provide stronger special resolutions that will allow us to look at emissions within large countries. I think we can get there.
Jonathan Faust, a sophomore studying international relations, is a staff interviewer at Stanford Political Journal.