7 to produce a liability. The discharge of that liability is equally simply measured with currently collected data.”20 Other proposals need not, of course, omit coal, the most polluting fossil fuel; it happened to be omitted in this particular proposal only because the proposal was attached to a legislative bill creating specifically an Oil and Gas Authority. How high a percentage of the carbon content of the coal, oil, or gas introduced under the certificate system would initially be required to be captured obviously depends partly on the limited maturity of the CCS technology now. However, the point would be to force all carbon vendors to invest sufficiently large sums in CCS to drive the technology rapidly forward, so the required percentage should be ratcheted up as quickly as possible until it reaches 100%. Then every additional ton of carbon extracted would have to be matched by a ton of carbon captured and sequestered for at least 10,000 years. All further carbon emissions vented are depleting the disappearing global carbon budget for any remotely safe temperature rise. Any carbon vendor who does not wish to invest in CCS, or a functionally equivalent technology, can invest instead in alternative energy - the choice between modification and substitution is the firms’. The choice between continuing to undermine the climate with carbon emissions and promptly ceasing, by contrast, is not theirs. 2.7 Carbon capture and further corporate evasion Two further stratagems threaten the modification route. First, carbon majors sometimes endorse CCS, but suggest that additional public spending should be the main source of additional R & D on CCS, as if the disruption of the climate has nothing to do with them. Like the requirement in the “Baker-Schultz Carbon Tax” that carbon majors be exempted from liability for the harm done by their insistence on business-as-usual long after the science established that their activities were progressively undermining the climate, this suggestion is merely another way of attempting to retain all the wealth accumulated from the process of disrupting the climate, while externalizing upon humanity at large all the costs of bringing the harm to an end. Convincing the general public to pay to make safe the use of the product that the carbon majors profit from providing for unsafe use would be another outrageous scam. Societies may decide that our current plight is sufficiently threatening that they are willing to bear some of the unfair financial burden belonging to the corporate majors that they ought not to need to bear, but that is entirely their choice. The burden of the clean-up properly falls on those who both made the original mess and are happy to continue indefinitely and knowingly deepening the mess. Second, and importantly, it may be proposed that later carbon removal - perhaps after an initial emissions “overshoot” - is as good as carbon capture at the time of combustion. This is not true, and any proposal to forgo capture in hope of removal is profoundly misguided. It is crucial that governments mandate carbon capture contemporaneous with combustion, not dream about later carbon removal after its release. I will very briefly indicate why. 21 First, although the vast majority of the integrated assessment models relied on for IPCC studies assume the availability ———————————— 20Myles Allen, Stuart Haszeldine, Cameron Hepburn, Corinne Le Quéré, and Richard Millar, Certificates for CCS at reduced public cost: securing the UK’s energy and climate future, Energy Bill 2015, SCCS Working Paper 2015-04 (Edinburgh: Scottish Carbon Capture and Storage, 2015). Copy attached to this statement. 21The reasons are laid out more fully in two recent articles: Henry Shue, ‘Climate Dreaming: Negative Emissions, Risk Transfer, and Irreversibility’, Journal of Human Rights and Environment, 8 (2017), 203-216. doi:10.4337/jhre.2017.02.02 (copy attached to this statement); and “Mitigation Gambles: Uncertainty, Urgency, and the Last Gamble Possible,”Philosophical Transactions of the Royal Society A, 376:20170105 (2018). doi:10.1098/rsta.2017.0105.