Here's my personal list of the most common and damaging myths about climate engineering. This is a pretty crude first effort, and I'm sure there's loads of omissions, poor wording, and of course missing references.
1 Precipitation will fall under SAI Not true. You can correct to baseline precipitation from prior climate, rather than to baseline temperature 2 Precipitation reduction is a crisis Precipitation isn't directly important. Soil moisture is probably a better proxy for NPP, as evaporation and transpiration both fall in a geoengineered world. NPP may actually rise, due to higher diffuse radiation. 3 Moral hazard has an evidence base There's as many papers on CE showing no or negative moral hazard. 4 Moral hazard is a key reason for not pursuing geoengineering Even if moral hazard exists, there's no reason to assume that business as usual will continue. There's already a global energy revolution starting, largely based on underlying economics, not on government interventions. Even if the pace of change slowed, there's no reason to assume that CE would result in a net-negative outcome. For example, CE would probably be a good trade-off for a 1pc reduction in rate of mitigation. (Of course, it could be higher.) 5 Technology risks and costs are low Lessons from other fields, summarised in at least one research CE paper, suggests that monitoring and regulatory costs of SRM will be a large, even overwhelming part of the cost base. 6 Volcanic analogues are adequate Major (and poorly understood) differences in rain out, coagulation, and particle size distribution exist between volcanic eruptions and SAI. This is mainly due to the step like input of sulfur vs quasi-continuous input for CE, but altitude is also an issue. 7 SRM Geoengineering will be unilaterally deployed by a powerful country or bloc It's unlikely that there would be a benefit to any minority deployer to act unilaterally and without appropriate consultation. No country is immune to global backlash, and making efforts to build coalition and consensus would be of benefit in most conceivable scenarios. 8 Deployers need to compensate for "damages" In reality, any nations actively involved in deployment (and thus temperature setting) would be backed by a larger or more powerful group (the winners) and possibly opposed by another group (the losers). Negotiations would be likely to engage both the winners and losers, to facilitate agreement. The concept of damages potentially implies that losses are fully traceable after the event, and that harms are not accompanied by simultaneous benefits. In reality, it may be better to to sort out any compensation based on predictions, not post hoc observations. A prepay settlement would be more predictable for all parties, and would eliminate credit risk. 9 Deployment has to be indefinite. Reducing rate of change of temperature provides a significant benefit, without requiring deployment for centuries. Further, if CDR is used, any reduction in temperatures started by SRM can be continued without. 10 Social science research is necessary before research to reduce societal risks. Delaying scientific and technical research means we're less well prepared, and risk deployment with less knowledge. This may outweigh any societal risks caused by rapid development. 11 SRM can reverse climate change Normally just a layman's error. SRM can't undo sea level rise (unless there's a huge undershoot on temperatures, not anticipated). It also doesn't restore perfectly the preexisting climate, with changes to polar amplification, diurnal temperature variation, etc., persisting. 12 SRM doesn't address ocean acidification. Forthcoming research by two groups show significant CDR benefits from SRM. 13 BECCS and other biomass CDR can make a big difference to CO2. None of the terrestrial CDR I've seen convinces me that there's a robust case for biomass CDR at the necessary scale. Costs and land use changes are simply impractical for the required scale of benefits required, and issues such as water and nutrient limits are problematic. 14 unleveraged CDR is viable Any CDR technique which doesn't rely on leveraging a natural process has costs which likely won't be tolerated by the global economy. 15 large scale rock crushing / spreading at reactivate dimensions is viable. Whilst some enhanced weathering approaches have important Co-benefits that make it viable, many of the problems of unleveraged CDR exist here. There's just too much expenditure required on crushing, and too much impact on the land, to do enhanced weathering at scale on land. 16 we need decarbonization of 100% of energy supply Because of intermittency, we need far more than 100pc renewables, ultimately. The residual energy flows can be stored, or possibly used to power CDR equipment in a few decades time 17 There's a slippery slope once CE technology development starts. The slope is slippery, but you have to get up it, not down. Most technology fails in development or commercialisation. It requires constant and expensive work to keep the technology current, and to promote it to potential buyers. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
