oggm.core.massbalance.RandomMassBalance

class oggm.core.massbalance.RandomMassBalance(gdir, mu_star=None, bias=None, prcp_fac=None, y0=None, halfsize=15, seed=None, filename='climate_monthly', input_filesuffix='')

Random shuffle of all MB years within a given time period.

This is useful for finding a possible past glacier state or for sensitivity experiments.

Note that this is going to be sensitive to extreme years in certain periods, but it is by far more physically reasonable than other approaches based on gaussian assumptions.

__init__(gdir, mu_star=None, bias=None, prcp_fac=None, y0=None, halfsize=15, seed=None, filename='climate_monthly', input_filesuffix='')

Initialize.

Parameters:

gdir : GlacierDirectory

the glacier directory

mu_star : float, optional

set to the alternative value of mustar you want to use (the default is to use the calibrated value)

bias : float, optional

set to the alternative value of the calibration bias [mm we yr-1] you want to use (the default is to use the calibrated value) Note that this bias is substracted from the computed MB. Indeed: BIAS = MODEL_MB - REFERENCE_MB.

prcp_fac : float, optional

set to the alternative value of the precipitation factor you want to use (the default is to use the calibrated value)

y0 : int, optional, default: tstar

the year at the center of the period of interest. The default is to use tstar as center.

halfsize : int, optional

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

seed : int, optional

Random seed used to initialize the pseudo-random number generator.

filename : str, optional

set to a different BASENAME if you want to use alternative climate data.

input_filesuffix : str

the file suffix of the input climate file

Methods

__init__(gdir[, mu_star, bias, prcp_fac, …])	Initialize.
get_annual_mb(heights[, year])	Like self.get_monthly_mb(), but for annual MB.
get_ela([year])	Compute the equilibrium line altitude for this year
get_monthly_mb(heights[, year])	Monthly mass-balance at given altitude(s) for a moment in time.
get_specific_mb(heights, widths[, year])	Specific mb for this year and a specific glacier geometry.
get_state_yr([year])	For a given year, get the random year associated to it.