This includes the set of balloon, aircraft, ground-based and satellite observational infrastructure assumed to be used to monitor aerosol properties during the first years of a deployment. An example of a way we could be wrong in our estimate, is that there turns out to be so much variation in aerosol size distribution spatially, that we need 10x more balloon launches to adequately monitor the distribution than had been expected.
Metric
Observational assets envisioned prior to deployment are insufficient to adequately assess stratospheric aerosol size and spatial distributions during early deployment (<0.1°C) such that these are still important uncertainties for 0.5°C-scale deployment
Uncertainty
Such an outcome is unlikely given experience with in-situ and remote sensing observations of stratospheric aerosols.
Decision relevance
This has cost implications, which are likely a small component of overall cost but could be significant if many additional assets are needed. More importantly, given the long timeline for launching new satellites, failure to resolve this uncertainty early could delay valuable data under early deployment.