Add postprocessing for 4D variables (lat, lon, time, pressure level)

[ph-kev]

Purpose

closes #1093 - This PR adds postprocessing for 4D variables (lat, lon, time, pressure level). See plots below.

To-do

• Make new release of ClimaAnalysis and update here in ClimaCoupler

Content

• Add bias plots after taking time average and slicing at specific pressure levels (850, 500, 250 hPA)

• Add bias plots over latitude and pressure level after taking average over time and longitude

• I have read and checked the items on the review checklist.
  
  

[Sbozzolo]

Looks good to me, thank you!

[juliasloan25]

This looks great! Thank you Kevin

[juliasloan25]

It would be good to also add a description of the new feature in NEWS.md

[juliasloan25]

Suggested change

	function `sim_var_dict`. Any preprocessing is done in the function which
	function `get_sim_var_dict`. Any preprocessing is done in the function which

[juliasloan25]

Which function does the preprocessing + unit conversion + date shifting? It's not totally clear to me here

[ph-kev]

I am going to rewrite this, but the function that does the post processing is the anonymous function defined in the dictionaries. For example, get_sim_var_dict returns a dictionary that map short names to functions and those functions are the one that do the preprocessing (unit conversion and data shifting).

[ph-kev]

The plots now look like this

[juliasloan25]

Thank you!

[ph-kev]

Going to merge this in, but it will be slow. This part of the postprocessing pipeline will be faster once this PR in ClimaAnalysis is merged in.