The @IPCC_CH #WGIII has released both its full report, along with a page-turning "Summary for Policymakers"! Some preliminary thoughts from @CarbonGap on the implications for #CarbonRemoval follow.

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First a reality check: emissions are outrageously high, STILL haven’t peaked, & continue to reveal massive gaps in ambition, development, and progress (e.g. North America per capita emissions 50% higher than the next highest region, 5x South Asia).

Is there any good news?

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Yes, of a sort!

1. Congrats to the 18 countries that actually reduced their emissions!
2. Prosperous, low(er)-carbon economies are becoming more plausible (e.g. Europe's per capita emissions are still high, but emissions per unit GDP are low)
3. Renewables got MUCH cheaper

4. 1.5°C is still (barely) in reach, but may require:

- Essentially NO new planned fossil infrastructure ("planned" emissions exhaust 1.5°C carbon budget!)
- Massive policy upgrade (2020 policies=3.2°C+!)
- 5-16 billion tons removal /year in 2050, net negative thereafter

Ok, back to our regularly scheduled carbon removal programming.

This Summary for Policymakers offers the most comprehensive and clear discussion of the importance of removals for securing our climate goals of any IPCC publication to date.

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Renewables have never been cheaper, and it's the direct result of "innovation policy packages" that incentivized large-scale deployment (@GregNemet tells it best, see

The same journey is possible for today's high-cost carbon removal techniques!

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We need deployment incentives for carbon removal that are sustained (decades), guaranteed (fixed $ amount), & technique-agnostic (all secure removal need apply!)

Sensitivity to "learning" effect varies (see below), we'll need to observe how each CDR solution stacks up

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Thank you to the IPCC for settling the carbon removal definition debate once and for all:

“​​CDR refers to anthropogenic activities that remove CO2 from the atmosphere and store it durably in geological, terrestrial, or ocean reservoirs, or in products”

Did the CO2 come from the atmosphere? Was it durably stored? If the answer to both of those questions is “YES”, it’s removal!

1) Biofuels? CO2 reemitted, NOT removal
2) Recycled industrial carbon in plastics? Not atmospheric, NOT removal

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The report cites three distinct roles for carbon removal:

1) Lowering net emissions (making clear we can start now)
2) Counterbalancing ‘hard-to-abate’ emissions (near-term)
3) Delivering net negative emissions (long-term)

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We would add one more often unmentioned role for CDR:

2.X) Counterbalancing emissions from Earth system feedbacks that result from warming itself, and threaten to take the biosphere & natural buffers from net sink to net source. Who will be held liable for such emissons?

I'm curious if @Oliver_Geden & colleagues view such risks as well-constrained + contained in the WG3-collated scenarios or if a disclaimer is needed: “if Earth system feedbacks generate more emissions than expected, we’ll have to remove those on top of the 5-16 GtCO2/yr by 2050!"
How much CDR will we need to keep peak warming below 1.5°C?

Rate in 2050: 5-16 GtCO2/yr
Cumulative amount 2020-2100:
- Direct air capture w/ storage (DACCS): 0-310 GtCO2
- Bioenergy w/ carbon capture (BECCS): 30-780 GtCO2
- Land-based carbon removal (AFOLU): 20-400 GtCO2

Beyond these marquee categories, the potential of various removal techniques crops up throughout the Summary, including:

- Soaking up and storing carbon in the built environment (C.6)
- Roles for removal-adjacent activities in delivering climate-safe transport (C.8)

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One clear output: we need nature on our side! Protecting, enhancing, and managing nature + managing biologically-mediated systems is critical to prevent further land conversion, remove carbon into resilient ecosystems, & (less explicitly) hold back Earth system feedbacks

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Nature can deliver 5GtCO2/yr removal + irreplaceable co-benefits: biodiversity, conservation, food & water security, livelihoods, improved land tenure, etc.

However, nature "cannot fully compensate for delayed action in other sectors" (C.9)

@cecilegirardin et al '21 below

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But the IPCC is also open-eyed on the barriers & potential risks of over-reliance on these solutions, including "uncertainty over long-term additionality, ...weak governance, insecure land ownership ...and the risk of reversal" (C.9.3)

These challenges are surmountable.

Finally: "The deployment of CDR to counterbalance hard-to-abate residual emissions is unavoidable if net zero CO2 or GHG emissions are to be achieved."

No CDR? No net zero.
No net zero? No peak warming; dire climate impacts.

The case for removal has never been clearer.

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Closing thought: Talking climate is hard through the limited dual lens of “adaptation & mitigation”. Given the unequivocal & outsized role of carbon removal, and the need to distinguish reductions from removals, we need to reframe climate action at the highest level.

A new proposal seeks to do just this: redefine climate action at the UNFCCC level into 3 such distinct pillars


Please share your thoughts, & if you want to help make this happen tag @deankhagram, @RethinkRemovals, & @CarbonGap to stay apprised


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More from @EliMLarson

Jul 2, 2021
We cannot deliver #NetZero with emission reductions alone. Carbon removal can play a complementary role to:

1) Eliminate some very hard-to-reduce emissions
2) Balance emissions from the Earth itself in a warming world
3) Restore the atmosphere, removing our past emissions

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And we'll need to consider a wide array of carbon removal techniques: storing carbon safely in forests, soils, oceans, mineralised forms above/below ground, and even long-lived products & building materials.

Neither nature nor technology can do this alone-we'll need both.

But CDR conversations in Europe are nascent and polarised. There are legitimate fears that removals will deter mitigation, + infighting among fans of specific CDR techniques, + little recognition that Europe's historical responsibility stretches beyond delivering net zero.

Read 9 tweets
Sep 29, 2020
Are carbon offsets still hot air? They don't have to be. Offsetting can be a powerful tool to achieve net zero emissions.

Introducing: the Oxford Offsetting Principles…

Two justifiable motivations for offsetting:
1) Taxing yourself - paying a "shadow carbon price" to disincentivise your emitting behavior. Only works when offset price is HIGH enough to motivate change. And...

2) Negating your impact - buying unreproachable offsets that unequivocally eliminate CO2. Only works when offset quality is HIGH (for the moment, that means price is high too)

Regardless of your motivation, the Principles will send you in the right direction.

Read 19 tweets

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