oggm.tasks.run_constant_climate(gdir, nyears=1000, y0=None, halfsize=15, ys=None, ye=None, bias=0, temperature_bias=None, precipitation_factor=None, store_monthly_step=False, store_model_geometry=None, store_fl_diagnostics=None, init_model_filesuffix=None, init_model_yr=None, output_filesuffix='', climate_filename='climate_historical', mb_model_class=<class 'oggm.core.massbalance.MonthlyTIModel'>, climate_input_filesuffix='', init_model_fls=None, zero_initial_glacier=False, **kwargs)[source]#

Runs the constant mass balance model for a given number of years.

This will initialize a oggm.core.massbalance.MultipleFlowlineMassBalance, and run a oggm.core.flowline.flowline_model_run().


the glacier directory to process


length of the simulation (default: as long as needed for reaching equilibrium)

ysint, default: 0 or init_model_yr

first year of the fake output timeseries. Since these simulations are idealized, the concept of “time” is only relative to the start of the simulation.

yeint, default: nyears

can be used instead of “nyears”


central year of the random climate period. Has to be set!

halfsizeint, optional

the half-size of the time window (window size = 2 * halfsize + 1)


bias of the mb model (offset to add to the MB). Default is zero.


add a bias to the temperature timeseries (note that this is added to any bias that the calibration decided is needed)

precipitation_factor: float

multiply a factor to the precipitation time series (note that this factor is multiplied to any factor that was decided during calibration or by global parameters)


whether to store the diagnostic data at a monthly time step or not (default is yearly)


whether to store the full model geometry run file to disk or not. (new in OGGM v1.4.1: default is to follow cfg.PARAMS[‘store_model_geometry’])


whether to store the model flowline diagnostics to disk or not. (default is to follow cfg.PARAMS[‘store_fl_diagnostics’])


if you want to start from a previous model run state. Can be combined with init_model_yr


the year of the initial run you want to start from. The default is to take the last year of the simulation.


name of the climate file, e.g. ‘climate_historical’ (default) or ‘gcm_data’

mb_model_classMassBalanceModel class

The MassBalanceModel class to use inside the ConstantMassBalance (default MonthlyTIModel)

climate_input_filesuffix: str

filesuffix for the input climate file


this add a suffix to the output file (useful to avoid overwriting previous experiments)


if true, the ice thickness is set to zero before the simulation


list of flowlines to use to initialize the model (the default is the present_time_glacier file from the glacier directory)


kwargs to pass to the FluxBasedModel instance


Files written to the glacier directory: