Graph with global temperature change with unchanged policy (° C above the pre-industrial average)

We can avert irreversible climate change

A renewed presidency for Donald Trump is nowhere more serious than for climate change. The coming decades will decide whether or not the risk of harmful and irreversible changes is averted. Success seems inconceivable without the active commitment of the USA. Even so, it would be unlikely. The decisive factor, however, is that this is conceivable. We know what to do and we also know it is affordable. What is unaffordable is not doing what we have to do. But will we? That is the question.

It is indicative of the shifting perspective of the global political establishment that a chapter of the IMF’s October World Economic Outlook focuses on “mitigating” – ie preventing – climate change through “growth- and redistributive strategies”. In short, the IMF insists that humanity can have their cake and eat it: both higher incomes and a safer climate.

As a result of increasing concentrations of greenhouse gases in the atmosphere, the global average temperatures are already around 1 ° C above the pre-industrial level. According to current trends, this could reach around 1.5 ° C in a decade and 2 ° C half a decade later. At this point, climate researchers warn that dangerous and irreversible turning points in the climate are likely to be exceeded. Most governments at least pretend to agree. In the Paris Agreement of December 2015, for example, they pledged to keep temperatures below these levels, even if their promises did not meet the requirements that were necessary to achieve this. (See diagrams.)

As the IMF notes, “Achieving this goal will require substantial and rapid reductions in CO2 emissions. In particular, net carbon emissions must be zero by the middle of the century. “To do that, emissions have to fall sharply this decade and continue to fall thereafter. That would be a major turnaround from previous trends.

What kind of program could produce this result? The answer, the fund says, is a combination of green investments, aggressive research and development funding, and a credible long-term commitment to rising carbon prices. This is in line with other studies, particularly Enabling a Mission: Delivering a Net-Zero Economy, a report by the Global Energy Transition Commission from September 2020. The latter also emphasizes complementary regulation to accelerate behavior change. Compensation for the poorer losers against the higher fuel prices will also be needed.

Graph showing that emerging markets will dominate the rise in emissions under normal conditions

Is a move towards zero net emissions by 2050 affordable? The answer is: surprisingly, especially given the economically weak starting point after Covid. The IMF estimates that achieving this goal could reduce world production by 1 percent from its “baseline” with policies unchanged, when adding the benefits of avoided harm. However, this must be placed in the context of the expected cumulative global growth of 120 percent over the next 30 years. It also ignores the benefits of much less local pollution.

Some estimates suggest that a rise in temperature of up to 5 ° C by 2100 could reduce global production by 25 percent without a slowdown. This does not take into account the massive non-economic disturbances of humanity, indeed of life as a whole, that can be expected from such an unprecedented rapid change in climate.

The graph shows that the five largest emitters can achieve most of the required emissions reductions

Given these estimates of the modest short-term cost of mitigation versus the much higher long-term cost of non-compliance, the case for action is overwhelming. This is all the more true if one takes into account the extent of the uncertainty caused by unchecked climate change and its irreversibility.

Taking action could make sense even if the costs were many times higher than expected. Why doesn’t it happen? One explanation is that these are lifestyle changes that we don’t like. Another reason is that you have to think in decades of what is unnatural. But the main explanation is that it requires long-term collaboration that we normally consider impossible.

Diagrams showing that reducing global emissions is feasible and must start now, while the economic costs of climate action will be very low

The collaboration between five actors – China, the US, the EU, India and Japan – would provide a large part of what is needed. Unfortunately, this doesn’t look likely at the moment. Shifting the US presidency to a healthy person would be of great help. Without that, sanctions against the US could be necessary. But moving China more aggressively than planned will also be essential.

Indeed, if necessary political changes are to take place early enough, it will require high-level statecraft. Domestically, programs need to compensate the most vulnerable losers, which is a good reason for applying a carbon tax. Internationally, the heads of state and government must work together far more effectively than under the Paris Agreement. If they are to do what it takes, leaders must overcome two other obstacles to smart action: the fossil fuel resistance fighters forever; and the ecological fanatics who advocate a revolutionary overthrow of capitalism and the end of growth – see you tomorrow, please.

Diagrams showing that targeted aid is the best way to compensate the poor for the costs of the energy transition

The only realistic hope is technocratic problem solving and cooperative politics. These must be guided by moral intentions, but must not be permeated by fantasies of revolutionary transformations. Shouts of “repentance, for the end of the world is near” will not resolve this emergency. Humanity is best when they use their heads. The climate is basically a crisis of technology and behavior; It can only be addressed by changing the incentives throughout the system.

As I said earlier, this is now extremely urgent. If we want to prevent a dangerous change in the planet’s climate, we must act far more decisively than before. We drink fossil fuels in the earth’s last chance. It is time for humanity to sober up.

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