This course is part of the GDRI CROCO-Sud Summer school that was held in Cape Town (South Africa) in November/December 2024. It is based on the ROMS-WRF course that I developped in 2018.

This advanced course in regional ocean-atmosphere coupling consists primarily of a series of tutorials (hands-on sessions), interspersed with lectures and seminars on air-sea interactions and modeling. It follows all steps to prepare a regional coupled CROCO-WRF configuration, ensuring that each component of the coupled system is explained in detail.

Specifically, the Air-Sea Week is organized around the execution of a set of 5 simulations. The first two simulations are CROCO forced simulations, in a stand-alone mode (day 1) and then coupled to a simple atmospheric TOY model (day 2) that receives CROCO surface fields. Similarly, the next two simulations are WRF forced simulations, and we use an ocean TOY model to send WRF fields (days 3 and 4). The final simulation is a fully coupled CROCO/WRF regional simulation (days 4 and 5).

Day 1 - 9h30-13h00 - 14h-17h00: CROCO DAY

• Welcome followed by a general introduction on the importance of air-sea coupling (Seminar)
• Overview of the CROCO OA-Coupling Advanced Week's activities and presentation of the models (CROCO, WRF, and two TOYs models) and coupler (OASIS-MCT) components
• Hands on sessions:
  • TUTORIAL0 :
    Installation of the coupling environment on the HPC. In this first tutorial, we will prepare the working environment for the CROCO OA-Coupling Advanced Week. We will connect to the HPC cluster, copy the source codes to run stand-alone and coupled CROCO and WRF simulations.
  
  
  • TUTORIAL1 :
    Run a forced inter-annual CROCO simulation (RUN1). We connect to the HPC cluster and run Matlab to create interannual CROCO input files using CROCO tools. We then compile CROCO and run the simulation on the HPC cluster.

Day 2 - 9h30-13h00 - 14h-17h00: Coupling CROCO with a simple TOY model

• Presentation of the coupling strategy/environment with OASIS-MCT
• TUTORIAL2 :
  Run the forced CROCO configuration in a coupled context (coupled with a TOY model) for a short period (RUN2), focusing on spatial interpolations. In this tutorial, we run a semi-coupled interannual CROCO simulation: CROCO is forced with bulk forcings while coupled to an atmospheric TOY model (atoy2d), which receives CROCO SST and surface currents. To run this simulation, we will need the OASIS-MCT coupler and the CROCO and ATOY models compiled in a (semi-)coupled context. CROCO forcings have already been created in TUTORIAL1, so we will focus on creating the files required by the coupler to communicate with ATOY and then run the simulation. We will work on the 2D regridding/remapping procedure, using various spatial interpolation techniques provided by OASIS-MCT.

Day 3 - 9h30-13h00 - 14h-17h00: WRF DAY

• Introduction to regional Atmospheric modeling using WRF model
• SEMINAR on atmopheric modelling
• TUTORIAL3 : Run a forced inter-annual WRF simulation (RUN3).

Day 4 - 9h30-13h00 - 14h-17h00: Coupling WRF to TOY and CROCO models

• TUTORIAL4 :
  Coupling WRF with an ocean TOY model, working on time transformation. In this tutorial, we run a semi-coupled interannual WRF simulation (RUN4): WRF is forced with SST and lateral fluxes from an atmospheroce Reanalysis, while it is coupled to an ocean TOY model (otoy2d) that receives WRF momentum, heat, and freshwater surface fluxes. We will need the WRF and OTOY models compiled in a coupled context. WRF forcings have already been created in TUTORIAL3, so we will focus on creating the files needed by the coupler to communicate with OTOY and then run the simulation. We will play with the possible time transformations (such as time-average or time-accumulation) of the exhanged fields.


• TUTORIAL5 :
  Perform your first fully coupled CROCO-WRF simulation (RUN5). Since all the input files have already been created, and the CROCO and WRF models have been compiled in a coupled context, we will focus on creating the single file required by the coupler (namcouple).