UN climate report: Carbon removal is now “essential”

It would require rapid transitions to new technologies as well as steep reductions in energy demand to cut emissions. It would take unprecedented human behavior changes and efficiency improvements, all of which would be quite challenging to accomplish in the real world, says Zeke Hausfather, a contributor to an earlier working group for the latest UN climate report and the climate research lead.

The goal of halving climate pollution to 29 billion tons by the year 2040 is being loosened.

The scale and speed of cuts required in both cases are not realistic, according to the chief scientist at Carbon Direct. He says that nations will need to do levels of carbon removal.

The world has emitted too much already. We haven't done enough to shift to cleaner ways of running our economies. We don't have affordable ways of fixing aviation, maritime shipping, cement, and steel.

The promise of carbon removal is that it can buy nations more time to shift to sustainable practices and balance out emissions from sources we don't know how to replace.

But

We are going to need to do a lot of it.

It would take billions of tons of carbon dioxide to prevent the planet from warming.

Three main methods of carbon removal were used by the models that limited warming to 2 ˚C. They would need to remove as much as 17 billion tons of carbon dioxide per year by 2050 and 35 billion by the end of the century, according to the report.

There is a need for a portfolio of carbon removal options.

Different approaches to carbon removal have different benefits and challenges according to the report.

Nature-based approaches like planting trees and restoring forests are the most popular today. The carbon can go back into the atmosphere when the plants die. Geological storage, which locks carbon away underground, is likely to last longer than these solutions.

The report states that direct air capture can permanently remove and store away carbon, but the machines are currently limited in scale and expensive, and the technology consumes large amounts of energy and water.

The models of the report lean heavily on BECCS, which is a hybrid of nature-based and technology-based approaches. BECCS requires a lot of land that could compete with food production, among other challenges.

Ocean-based approaches like using minerals to increase the alkalinity of seawater are included in the report. These are mostly unknown.

4. Funding and policy decisions are needed for scaling up.

The authors of the climate panel stress that it will take a lot of research and development to achieve high levels of carbon removal.

The ClimateWorks Foundation, which funds carbon removal research efforts, wrote a response saying that they need all hands on deck to explore a diverse set of options.

Cost is likely to be the biggest hurdle to building a major carbon removal industry. Who is going to pay the hundreds of billions to trillions of dollars it will run to remove this much carbon dioxide year after year?

It will require political commitment from governments to get businesses to do carbon removal, according to the report.

If history is any guide, the grim findings of a new IPCC report won’t radically change anything. The world is pumping out about 6 billion more tons of annual emissions than it was when the last major assessment was published, in 2014. But more and more work is happening on carbon removal as the importance of its role in combating climate change becomes ever clearer.