Sustainability limits needed for CO2 removal: Science Policy Forum.

[NNadir]

The paper to which I'll refer is in the current issue of the journal Science: Sustainability limits needed for CO2 removal, Deprez Deprez, Leadley Leadley, Dooley Dooley, Williamson Williamson, Cramer Cramer, Gattuso Gattuso, Rankovic Rankovic, Carlson Carlson, Creutzig Creutzig Science 383 6682 2024.

The article, which regrettably requires a subscription, is from the Policy section of the journal, specifically the Climate Policy section.

It contains some refreshingly blunt assessments of some the wishful thinking one hears almost continuously these days, particularly with respect to land use and poverty.

Since the article is not open sourced, I'll excerpt some interesting statements. All bolding will be mine.

Some excerpts, beginning with the introductory paragraph:

Many governments and industries are relying on future large-scale, land-based carbon dioxide (CO₂) removal (CDR) to avoid making necessary steep greenhouse gas (GHG) emission cuts today (1, 2). Not only does this risk locking us into a high overshoot above 1.5°C (3), but it will also increase biodiversity loss, imperiling the Kunming-Montreal Global Biodiversity Framework (KMGBF) goals (4). Such CDR deployments also pose major economic, technological, and social feasibility challenges; threaten food security and human rights; and risk overstepping multiple planetary boundaries, with potentially irreversible consequences (1, 5, 6). We propose three ways to build on the Intergovernmental Panel on Climate Change (IPCC) analyses of CDR mitigation potential by assessing sustainability risks associated with land-use change and biodiversity loss: estimate the sustainable CDR budget based on socioecological thresholds; identify viable mitigation pathways that do not overstep these thresholds; and reframe governance around allocating limited CDR supply to the most legitimate uses.

Achieving the Paris Agreement climate goals primarily depends on deep, rapid, and sustained reductions in GHG emissions, including steep reduction in fossil fuel production and use (3, 7). Yet some CDR will also be needed in coming decades to reach “net zero” (by counterbalancing hard-to-abate residual GHG emissions), and then “net negative” emissions (to help reverse any temperature overshoot above 1.5°C)...

... The latest IPCC Working Group III (WGIII) report estimates the upper “technical mitigation potential” of BECCS and A/R at 11.3 and 10 gigatonnes of CO₂ per year (GtCO₂/year), respectively (3). Together, this could require converting up to 29 million km² of land—over three times the area of the United States—to bioenergy crops or trees, and potentially push over 300 million people into food insecurity [see supplementary materials (SM)]. The upper end of the IPCC’s BECCS technical potential does not take into account socioeconomic barriers or the transgression of planetary boundaries, but the A/R potential takes into consideration food security and environmental impacts. The IPCC report does not provide details or quantitative evaluation of how sustainability risks vary with increasing levels of A/R or BECCS deployment (3).

We compare IPCC mitigation potentials with recent studies that give greater attention to the ecological, biological, and societal impacts of land-based CDR (see SM), to provide quantified sustainability limits...

"A/R" here refers to afforestration/reforestration.

What's the starvation of 300 million people and the rendering three times the area of the United States into farms for biofuels between friends?

...We estimate low risk levels for “nature-based” CDR to be up to about 2.6 GtCO₂/year, including up to 1.3 GtCO₂/year from reforestation. These are considered low risk levels because they focus on restoration and involve very limited land-use change (see the figure and SM). Our evaluation of medium risk allows for land-use change up to levels that studies concluded are unlikely to substantially infringe upon sustainability limits. The upper bound of medium risk is about 5.1 GtCO₂/year for “nature-based” CDR, including up to 3.8 GtCO2/year from reforestation. These are far below the upper bounds of technical mitigation potential and even below the more tightly constrained economic potential identified by IPCC WGIII (see the figure)...

Hopefully all those new forests won't do what forests have a habit of doing in these wonderful days of climate change: Burn.

Anyway...

It's not like we should compare the "low risk" here, whatever it might be, to the much hyped risk in this space and elsewhere among functional idiots that someday somewhere someone might die from radiation exposure at Fukushima. (Thus far, radiation deaths from the event have not been unambiguously observed.) The rhetoric behind this detestable morally void calculation is that nuclear energy is "too dangerous" but climate change isn't "too dangerous." This also reflects on the similar calculation made by ethically challenged people that nuclear energy is "too expensive" - this because the benefits will accrue to the future generations about whom we couldn't give a fuck - and leaving the planet in flames for those generations is not "too expensive."

Although I have had much happiness in my life, I won't feel too bad about getting kicked out of being in a world, biting the bullet, shuffling off this mortal coil. going off to the great beyond, what have you, on a planet where calculus of this type prevails, where it is not regarded with extreme disgust. It's unbelievably clueless.

As for the "low risk" rates of removal for "nature based" CDR, carbon dioxide removal, 2.6 gigatons per year and as for "medium risk," 5.1 gigatons per year should be compared with the emissions chiefly from fossil fuels, which is currently on the order of 35-40 gigatons per year as of this year.

Don't worry; be happy:

If any of this troubles you, well why don't you buy a happy book by a "political science" doctoral student with wind turbines on the cover. Then, I'm sure, you'll be happy, especially if you ignore the land use and material costs of building zillions of wind turbines and replacing them every 25 years.

Or else you can head over to Cleantechnia and read all kinds of wonderful news about Apartheid Elon's wonderful electric cars.

I'm sure you'll feel better.

As for me, if I sound outraged, it may be connected with the fact that I am so.

Have a great weekend.