A new theoretical framework for parameterizing nonequilibrium fractionation during evaporation from the ocean

This archive includes the surface flux model described in "A new theoretical framework for parameterizing nonequilibrium fractionation during evaporation from the ocean", submitted to J. Adv. Model. Earth Sy. It also includes the subroutines for the new parameterization in iCAM6, output from the iCAM6 simulations, as well as Python scripts and notebooks for creating the figures. Surface flux model All code related to the surface flux model is in surface_flux_model.zip. The main script is called surface_flux_model.py. Parameters for the surface flux model can be adjusted in surface_flux_parameters.py. The plotting scripts are named plot_<something>.py. iCAM6 simulations The model output from the iCAM6 simulations is in icam6_output.zip: Monthly averages of H2OV, HDOV, and H218OV at the lowest model level from 2007-01-01 to 2020-12-31 are saved in nudged_clim_old_alphak.nc (default parameterization), nudged_clim_const_alphak (constant αk) and nudged_clim_new_alphak.nc (new parameterization). The file nudged_clim_new_alphak.nc additionally includes U10, PS, TREFHT, TS, LHFLX, SHFLX. Hourly averages of H2OV, HDOV, and H218OV at the lowest model level are saved separately for each field campaign on limited domains covering the extent of the campaigns. The files are named nudged_<campaign>_old_alphak.nc (default parameterization), nudged_<campaign>_const_alphak (constant αk), and nudged_<campaign>_new_alphak.nc (new parameterization). The files nudged_<campaign>_new_alphak.nc additionally include U10, PS, TREFHT, TS, LHFLX, SHFLX. The subroutines for the new parameterization in iCAM6 are in water_isotopes.F90. The scripts for the analysis are in icam6_scripts.zip. The notebook results.ipynb calls the necessary python modules (icam.py, util.py, functions.py) and creates the figures for the iCAM6 simulations. It assumes that the measurements from the field campaigns are located in a subdirectory called measurements/ (see the references cited in the manuscript for access to the data). The functions for reading the measurements may need to be adapted depending on the format of the downloaded files. Python environment The Python scripts and notebooks run with Python version 3.10. Required packages are listed in the file environment.yml, which can be used to create a conda environment: conda env create -f environment.yml