AGW mitigation plans
Many plans have been devised for mitigating and adapting to climate change. These greatly vary in detail, and in the degree of scientific rigour upon which they are based.
The gold standard for such plans is the work of the IPCC Working Group 3.
Energy decarbonisation plans are concerned with energy production and consumption, which is responsible for a large proportion of CO
In an essay: Contending with climate change: The next 25 years (Bulletin of the Atomic Scientists; 10 Dec 2020; [pdf]| [local copy]) Robert H. Socolow discusses his thoughts on how mitigation might progress in the near future.
Any successful effort to address climate change over the next 25 years will involve a “credible swap” that greatly reduces greenhouse gas emissions from the burning of fossil fuels, provides energy in entirely different ways, and also reduces demand for energy. On the demand side, the next quarter century offers abundant high-leverage opportunities to reduce future emissions via intelligent urban design, building construction (notably in the gigantic apartment complexes), and efficient vehicles and appliances. On the supply side, there are three variants of the swap. In one, the work horse is renewable energy (solar power, wind power, hydropower, and power from biological feedstocks); in a second it is nuclear power; and in a third it is a reshaped fossil fuel economy. The three are by no means mutually exclusive. Each brings disruption and risks, rivaling those of climate change if done inattentively. Well-executed solutions will require threading a needle.
The centennials of Hiroshima, Nagasaki, and the founding of the Bulletin of the Atomic Scientists are only 25 years ahead. When I think about the next 25 years, I see the people of this planet wrestling with a reality that has only recently emerged. For the first time in human history, we human beings, doing ordinary things, can alter our entire planet in ways that are harmful to ourselves. And every available strategy to work around these limitations is fraught, so we need to be clever and clearheaded and wary. Fitting on our planet, rather than bursting its seams, is going to be difficult. It will preoccupy many successive generations.
Climate is one of many examples of potential seam-bursting – others include arable land and fisheries – but climate is the one I have thought most about. We are vulnerable to environmental disruption because what makes us distinctly human is finely tuned to a planet that has been quite stable. An apt example is sea level. During Earth’s exit from the most recent ice age, from approximately 14,000 to 6,000 years ago, sea level rose 130 meters. But it has changed very little during the past six millennia, with the result that many of the world’s cities have been built at the edge of an unchanging sea. A mere two meters of sea level rise would require extensive changes to these cities and abandonment of some of them.
The largest agent of the climate portion of our newly challenging reality is the carbon dioxide that results when we burn fossil fuels. Because of their high energy density, it is economic to move fossil fuels over global distances by rail and ship and pipeline, enabling global markets. Costs are modest because the best geological sources are highly concentrated: thick seams of coal and expansive reservoirs of oil and natural gas. And the fossil fuels are abundant, in the sense that they could meet the world's energy needs for centuries (although probably not for millennia).
Indeed, there would be little pressure today to move away from a global economy based on fossil fuels if it weren’t for their Achilles heel. The carbon dioxide created by burning fossil fuels has routinely been sent to the atmosphere, where, we now appreciate, it has a potent role in driving climate. The Earth cools off to space via infrared radiation at wavelengths where nitrogen, oxygen, and argon are essentially transparent. As a result, three-atom molecules dominate the cooling process, and of these, carbon dioxide is second only to water vapor in its importance. Nasty climate impacts are showing up already, and impacts will get worse.
We are only just beginning to scope the modifications of currently dominant practices that we will need to pursue on a planetary scale over many decades in order to sustain our well-being (Pacala and Socolow 2004; Socolow 2011). Our collective assignment in the energy domain is to swap out fossil fuel use everywhere. A major political instrument is the 2015 Paris Accord. The objective it establishes, in effect, requires cutting global carbon dioxide emissions approximately in half over the next 25 years. In turn, this requires lowering the per capita emissions in the industrialized countries to the current level in the less developed countries, while the less developed countries figure out how to industrialize without adding to their own emissions. To those who wish “fairness” to take the form of prolonged rising emissions trajectories in developing countries that mimic those of the countries that industrialized on the backs of coal and petroleum half a century and more ago, the message is unpleasant: Safe is not fair, and fair is not safe (Tavoni, Chakravarty, and Socolow 2012).
The Paris Accord is a recurrent pot-luck dinner. Each country comes with its best dish – some carbon-relevant initiative like a build-out of electric vehicles or a carbon tax or a reforestation measure – and the other countries inspect it. They are supportive. (No one makes fun of a collapsed cake.) Every country looks at the other offerings and thinks, I could try to show off that dish when I come back in five years. The Paris Accord is brilliant diplomacy, designed to create a race to the top. Tough targets are motivating governments and industry to start decarbonizing. Of course, the first offerings aren’t that impressive, but a path forward, at least for the next 25 years, has been created. It could work.
One problem with the potluck-dinner metaphor is that it leaves out the cross-national role of civil society, whose independent evaluations of national offerings constitute another important part of the Paris process. If a country brings forward a dish that is not what it seems – whether as a result of deliberate deception or self-deception – the diplomats are counting on external critics to step in.