Green Shoots: 365 Days of Climate Awareness 344 – AR6 Vol 3, Chap 1: Introduction to Climate Mitigation

As of 2019, the planet’s current and likely mitigation plans will fail to limit global warming to 1.5°C/2.7°F over 1750 temperatures by 2050. We are very likely to miss the Paris Agreement’s target: 2.0°C/3.6°F is now a more realistic goal. Even though emissions in recent years have slowed, and at current rates are likely to peak by 2030, the anticipated emissions by that point will almost ensure global temperature rise of 2.0°C/3.6°F or more. In short, plans for “net zero by 2050” are inadequate when they allow for maximal emissions leading up to that year. In physics terms, the pathway—emissions through time, not simply the end state of the climate system—is important.

All illustrations from the IPCC 6th Assessment Report, Vol. 3, Chap. 1. Emissions and population trends.

Regional emissions trends by source.

Several greenhouse gas emissions plans are consistent with the UN’s 17 Sustainable Goals, a set of principles for bringing economic and social opportunity to less wealthy countries in an equitable and environmentally responsible way. The UN has no authority, however. Nations retain their full sovereignty, and the sustainable development goals remain as aspirational as the Paris Agreement. The principle means for decarbonizing are technological, increasing efficiency and developing less carbon-intensive machines and processes, and economic, limiting growth and shepherding investment toward more sustainable industries. Of these two, technology is much the easier to encourage, but is the less significant climatically. Economic changes require overcoming extremely powerful vested interests, such as the petroleum industry and governments funded by it. Neither avenue alone is sufficient to limit global warming to even 2.0°C/3.6°F by 2050.

Renewable energy capacity and levelized cost of energy (LCOE). LCOE = cost, in current dollars, per unit energy over the installation's lifetime (an important investment metric).

Pathways to sustainability for various countries in different states of development.

No one sector alone—popular (i.e. individual), industrial, or governmental—will suffice to strategize for and accomplish decarbonization. Nor will activity at any one level—local, regional, national, or international. All are required to work together to some degree to meaningfully mitigate global warming. This is the cost of four decades’ delay, after the initial warnings were sounded in the late 1970’s and early 1980’s. We have run out of time. While policy and societal change can still succeed in limiting global warming and staving off some of the most extreme effects, in terms of ice melt and extreme temperature rise, concerted, global action is required now to make the changes in time.