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Isn’t shipping responsible for much more co2 emissions than air travel? Like 17% vs <2% Making ships less dirty + simplifying supply chains would prob make much more difference
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Not on a per-pound-per-mile basis, plus air travel has higher impact emissions because stratosphere altitude emissions cause about 4x more impact for same amount of CO2.
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Not to say it won’t become a political hot topic - but like plastic straws, or fox hunting in the UK, it’s a symbol and a proxy for a whole bunch of other things
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I knew you’d make plastic straw comparison 😆 The analogy is off. Plastic straw bs is based on misinformation around a rounding-error part of a problem (0.5% of oceanic plastic waste) Air travel is like 10% under proper accounting, and the thinking around it is mostly correct.
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2% is the airlines figure for base emissions. It gets to 10% once you factor in altitude multiplier effect of about 4x-5x I believe. Stratosphere emissions have much stronger radiative forcing effects.
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2 only gets to 10 if only airline emissions are subject to this multiplier (and you do nothing to the denominator - but it’s close...) - id love to see the source for this.
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But yeah, 10% is sort of my working estimate of a worst-case bound for quick and dirty thinking. Probably too pessimistic. I’d say 5% would be the optimistic bound which is still a nice wedge worth working on. Most things people talk about are like dumb 0.5% wedges.
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As a merchant sailor: Shipping is legislated in an ad-hoc manner because of the hyper complex legal structure around it. But there is NO way to beat it for efficiency. We need better engines/fuels Bouyancy is free, build a boat, it floats. Lift (airplanes) requires energy.
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