Model code and solution dataset for "Glacier surges and seasonal speedups integrated into a single, enthalpy-based model framework"

This repository holds the model code and output simulations produced for Terleth et al. Glacier surges and seasonal speedups integrated into a single, enthalpy-based model framework. Submitted to Geophysical Research Letters.

Model code: This is a matlab version of the enthalpy based numerical model simulating glaciers surges presented in Benn et al. (2019) (doi:10.1017/jog.2019.62). It includes an additional feature forcing seasonality in the evolution of surface air temperature, implementing seasonality within the model. The code also focusses on evaluating the impact of changing supply and drainage volumes to the subglacial drainage system, rather than the climatic conditions around the glacier.

• MAIN_envelope.m is the wrapper script that runs the model, iterating through parameter combinations.
• ode_MAIN.m contains 4 ordinary differential equation and is given to the solver.
• constants.m is simply a list with all the constants given in Table 1 in Benn et al. (2019). This version of the model recalculates most of these based on the input parameters.
• adjust_constants.m recalculates the constants based on the input parameters. Definitions of all the recalculated constants are from the appendix in Benn et al., 2019.
• plot_return_periods.m plots the surge interval for various versions of the model.
• plot_specific_run.m lets users choose a parameter combination for which to plot tha model output as normalised timeseries.
• the matlab_helpers zip files contains useful helper functions for plotting. should be unzipped and put in the working directory for the plotting scripts to work. The functions are generally from the matlab file exchange and should ahve credits to authors within.

Model solutions produced for the paper are contained in the .zip file model_solutions_a_0.6_Ta_-8.zip. a and Ta refer to the climatic parameters common to all solutions. The files can be plotted using plot_return_periods.m and plot_specific_run.m.

The structure of the filenames in the .zip file follows: params_gp_[beta_min]_kp_[K].mat where [beta_min] is the parameter value describing the minimum fraction of meltwater reaching the distributed drainage system and [K]*K_{0} is the value of basal hydraulic transmissivity. The file FINAL_workspace.mat contains the values of all the fixed parameters.