Added IGCM4 L20 gp_nudging functionality (see Dow et al., 2023)

Added the code and instructions to implement the IGCM4 L20 gp_nudging functionality as used in Dow et al., 2023.

Minor Updates

v2.0.1: Minor Updates, including the addition of a Documentation folder and minor bug fixes for the IGCM4 compilation script.

FORTE 2.0: a fast, parallel and flexible coupled climate model

FORTE 2.0 is an intermediate resolution coupled Atmosphere Ocean General Circulation Model (AOGCM). As released, it consists of IGCM4, a T42 spectral atmosphere with 35 sigma layers, coupled to MOMA, a 2° x 2° ocean with 15 z layer depth levels. It is capable of producing a stable climate for long integrations without the need for flux adjustments.