hesgenEminent environmental engineer Sir Simon Jenkins writes...
"Sunak’s plan for carbon capture is good news: he shouldn’t muddy it with party politics"
Simon Brooke@hesgen No, it really isn't good news. #CarbonCapture #CCS will never be more than #Greenwashing – a modern equivalent of the perpetual motion device. We don't have time (or resources) for these distractions.
But Sir Simon hath spoke!
@hesgen If anyone knows that it isn't always wise to do what Simon Says, it's me.
@hesgen And, oh, Jings! To criticise this in more detail, Simon says (quoting an 'expert', Stuart Haszeldine):
"Existing #CCS currently reduces CO2 emissions by 0.1%. To meet net zero, it needs to rise to 10%."
Can anyone spot the order of magnitude error in that?
@simon_brooke Two orders of magnitude.
@hesgen I'm prepared to be wrong, but please show your working.
@simon_brooke 10/0.1=100.
@simon_brooke A one hundred-fold increase in engineered carbon capture is required to meet the net zero target. That's a two orders of magnitude increase.
@simon_brooke There are other carbon sinks in the equation. For CCS, it needs to rise to 10%.
@hesgen What are these other sinks, and how do they scale with emissions?
@simon_brooke Oceans, forests, soils and sedimentary rocks are four of the major (natural) carbon sinks. Their respective scales are far too complex a matter to deal with in antisocial media posts. There is a world of research literature out there, with much of it open-access.
@hesgen Sure. But those things have all been absorbing carbon for the past millenia, and they absorb just enough carbon to keep the system in equilibrium: they cycle it. If they didn't, the amount of in-cycle carbon would have been declining dramatically over time, and there wouldn't be enough left now to sustain life.
So – unless we are substantially increasing the net amount of standing timber in the world (hint: we're not) the carbon they absorb cannot be counted towards #NetZero.
@simon_brooke They can and must be counted toward net zero, but the numbers involved are a work in progress. Also, it is unwise to talk of "equilibrium" in planetary systems. There are balances on all sorts of timescales, but these systems are forever in a state of dynamic disequilibrium.
@hesgen Seriously, if the natural carbon cycle was permanently sequestering carbon, there would be no carbon left to make your body or mine. The only carbon it is currently sequestering is the carbon represented by the existing biomass on the planet. The only way we can increase the amount it sequesters is to increase the amount of biomass, but we're currently sharply DECREASING that. So it's no longer a net carbon sink in the first place.
#1/several
Simon, I recommend that you read up on carbon sources as well as sinks, latencies, and feedback mechanisms, both positive and negative. Achieving net zero requires a rapid phasing out of fossil fuels. The value of engineered carbon capture and storage is an open question, with no expert consensus.
@hesgen I'm not arguing about whether #CCS at scale is possible – I'm deeply skeptical, but that's a different argument. I'm arguing about what proportion of carbon from fossil fuels extracted has to be permanently sequestered: and it clearly has to be 100%. Otherwise, anthropogenic #GlobalWarming will continue without limit (well, without limit until we're all dead).
There is no capacity on natural systems to do this: they're necessarily at capacity already.