On "Legislating science".
Are you sure that this is the real motivation?
It makes sense to me that an area that has a lot of coastline real estate activity would want to settle on a model.
I don't think that the motivation was to settle on a particular model, but just that there should be a single model that everybody can refer to.
Otherwise, every project would have to call in a climatologist (or choose a published report) and maybe pit "my climatologist" against "your climatologist". No matter would be settled and the projects would be impacted by an ongoing discussion way outside their field of expertise.
Steve asked "why linear"? I don't think anybody necessarily lobbied for "linearity" because it would "serve" any given party. I think a published timetable based on a complex mathematical model would serve the same purpose. The point is to reach a common reference for future prediction on large scale projects.
Especially when calculating project costs and project margins, you DON'T want people manipulating the data or see a project plan estimation turning into the same climate debate that another project just had.
I do hope that they used climatologists to produce their linear approximation model. Granted, it is probably not accurate, but there is a benefit in locking the model in place.
But isn't the state putting itself liable for financial loss based on this model?