Seasonal analysis

[dlawrenncar]

Putting an issue in here to record the need, I think, for us to talk (again, I know we have talked before) about implementing seasonal mean analyses into ILAMB, perhaps like what they do in PMP. When using the CLM diagnostics package, we more often look at seasonal average results rather than annual mean.

[nocollier]

We can do this, certainly in ilamb3, but presuming that takes me too long to complete, I could add it here.

My main hesitation is related to the fact that we precompute all the images. There are currently 2.9Gb of images in our CMIP5v6 comparison. So if we add 4 seasons to the analysis, this would lead to > 10Gb output directories. This is of course not the end of the world if it is what the community wants, but it starts to become cumbersome to deal with.

I am hoping that we can have more dynamic visualization in the future and this would relax this.