numbers, not adjectives — D. J. C. MacKay

4  One climate question to rule them all

The solution to the global problem of climate change may seem complex and multifaceted. Should we plant trees? Or invest in Direct Air Capture technology? Invest in a Global Green Fund? Price carbon? Insulate homes? The list goes on.

A necessary prerequisite for solving a problem is to understand its essence, and avoid getting lost in the weeds of the details. In other words, clarity of thinking.

What is the one central climate question, the one that encapsulates the essence, the one whose answer renders other questions insubstantial? This question is:

What mechanisms can avoid that humanity burns the majority of recoverable fossil fuels?

To date we’ve burned about a third of known recoverable fossil fuel reserves. Burning the current reserves (∼1 million million tons of coal, ∼1.5 million million barrels of oil, ∼200 million million cubic meters of natural gas) would produce ∼4 million million tons of CO₂, increasing the atmospheric concentration from 425 ppm (now) to 650 ppm, or about +4°C, or possibly more, from preindustrial times. While estimates of global fossil fuel reserves vary, the bottom line is, that the consequences of burning close to all readily available fossil fuels will have dire consequences for the majority of future populations.

Why is this the right question to ask, and not other commonly asked questions? It’s because the answer to the question overwhelmingly determines the fate of human populations.

The problem is that this, most relevant of all climate questions, is not being asked, let alone answered. The media talks endlessly about the various bits of political progress on assorted digressing questions at the annual COP meetings, all the while emissions keep growing and the atmospheric greenhouse gas concentrations increase at ever increasing rates.

Refusal to engage with the real issue, and perpetual flooding of the discourse with distracting side agendas, benefits only the parties who want to delay and avoid solving our actual predicament. Instead we need clear and focused thinking. We need to rise up and address the climate question which rules them all.

4.1 Two possible answers

What are the mechanisms that may avoid burning all fossil fuels? Two flavours of answer are often suggested. One is that renewable energy becomes so abundant and cheap, that it is no-longer economically viable to extract fossil fuels. The alternative may be that nations globally agree to cooperate to limit fossil fuel consumption in order to avoid the destructive consequences of climate change.

4.1.1 Abundant, cheap renewables

What are the conditions under which individual economic incentives may solve the climate problem? For example, it is often quoted that the price of solar panels have tumbled in recent times so that renewables may now be cheaper than fossil fuels. While it may be true that the marginal cost of adding another kWh capacity may be cheaper for renewables, caution is needed. Firstly, the cost of a power network is not equal to the marginal cost of unit production times the size of the capacity; especially not when relying on intermittent sources. Storage is expensive, and infeasible between seasons. Secondly, it is currently infeasible at scale to completely avoid fossil fuels, which can be switched on at any time. Proposals relying on Carbon Capture and Storage (CCS) cannot be deployed in solutions motivated by being the cheapest alternative, as CCS is an additional, costly component, leaving it out will always be cheaper. Finally, some uses of fossil fuels, such as air transport, are not currently displaceable but renewables.

The above arguments show while some fossil fuel solutions may be replaceable by renewables, it is unlikely that complete coverage is possible by renewables when competing on price alone. The good thing is that the price incentive will be a strong driver of adoption of renewables. But realistically, this will apply only to a fraction of fossil fuel use.

This means that we either continue using fossil fuels, where they remain the cheapest option, and therefore accept that we will burn all the available fossil fuels (although maybe at a slower pace). Or alternatively, we would have to collectively agree not to use fossil fuels even in situations where they remain the cheapest option. This choice would of course make sense economically too, once the price of avoiding the most devastating aspects of climate change is factored in.

4.1.2 Global cooperation

How could agreement not to burn fossil fuels, even when they’re cheaper, be enabled? Clearly, this will require global cooperation. It is unsustainable to think that nations can act individually, incurring additional costs, if other nations chose not to, and thus create an uneven economic playing field, and prevent undermine climate outcomes.

To even start such as discussion, one needs to define what is meant by “fair”. Fairness is a moral and ethical judgement, but few would contend with the idea, that fair means equitable, ie equal for all people. And this is a great starting point. It would be unreasonable that the people of some nations have more rights to pollute our globally shared atmosphere than the people of other nations. If one nation insists on using more than their equitable, fair share, it would be reasonable that they pay for it. Thus, these very basic principles of equity leads immediately to that conclusion that we must globally price carbon.

A second problem arrises if or when nations refuse to join a carbon price cooperative. We have no global government who can force nations to cooperate. Thus, we must introduce penalties for free-riders; the most obvious candidate would be trade barriers, also sometimes known as Carbon Border Adjustment Mechanisms (eg EUs CBAM).

4.2 Next steps

We’re seen that cheaper renewables will likely incentivise elimination of some fraction of fossil fuel use, but not all. It’s important that we collectively think seriously about how the remaining fraction can be dealt with. It will require global cooperation, within a strong legally binding framework (not the weak, non-binding variant present in the Paris Agreement). The starting point must be stating the principles of fairness and equitability, and creating a coalition of the willing of nations ready to adopt such principles.

Global cooperation may be a tall order, but if not adopted, the consequences will in all likelihood be that we burn all recoverable fossil fuels, and the dire consequences of +4°C or more.

It’s our choice to make.

Pretending that this isn’t the choice facing us won’t help.