Slider for initialisation date

[tom-andersson]

Would great for research purposes to be able to control the initialisation date for the forecast. I would envisage this as a slider.

We could then, for example, go back in time and look at whether IceNet correctly predicted the record low Antarctic sea ice maximum extent this year.

One complication might be getting the target date slider to update as the initialisation date is changed, unless this is inferred dynamically?

[JimCircadian]

The target date isn't an issue, but the concept of the slider for this is. Basically, we can allow the user to select from a list of available initialisation dates, but a slider isn't really appropriate at this stage. Will implement this and it gives rise to some other potentially interesting plots that could be possible

[tom-andersson]

Right, if we can't expect all initialisation dates to be available then a list of available init dates makes more sense.