Derivation of under-ice, mixed layer PAR values from profile measurements during MOSAiC

Python code to process PAR data from autonomous, ice-tethered buoys OptiCALs and lightharp on MOSAiC. Derives average PAR in the under-ice mixed layer and at the ice bottom. Corrects for local and large-scale inhomogeneities in the snow and ice cover, impacting transmissivity. Uses the model approach suggested by Laney et al. 2017. Furthermore, an example plot of measured profiles with valid and invalid fits is prepared.