def distribute_thickness_interp(gdir, add_slope=True, smooth_radius=None, varname_suffix=''): """Compute a thickness map by interpolating between centerlines and border. This is a rather cosmetic task, not relevant for OGGM but for ITMIX. Parameters ---------- gdir : oggm.GlacierDirectory the glacier directory to process add_slope : bool whether a corrective slope factor should be used or not smooth_radius : int pixel size of the gaussian smoothing. Default is to use cfg.PARAMS['smooth_window'] (i.e. a size in meters). Set to zero to suppress smoothing. varname_suffix : str add a suffix to the variable written in the file (for experiments) """ # Variables grids_file = gdir.get_filepath('gridded_data') # See if we have the masks, else compute them with utils.ncDataset(grids_file) as nc: has_masks = 'glacier_ext_erosion' in nc.variables if not has_masks: from oggm.core.gis import interpolation_masks interpolation_masks(gdir) with utils.ncDataset(grids_file) as nc: glacier_mask = nc.variables['glacier_mask'][:] glacier_ext = nc.variables['glacier_ext_erosion'][:] ice_divides = nc.variables['ice_divides'][:] if add_slope: slope_factor = nc.variables['slope_factor'][:] else: slope_factor = 1. # Thickness to interpolate thick = glacier_ext * np.NaN thick[(glacier_ext - ice_divides) == 1] = 0. # TODO: domain border too, for convenience for a start thick[0, :] = 0. thick[-1, :] = 0. thick[:, 0] = 0. thick[:, -1] = 0. # Along the lines cls = gdir.read_pickle('inversion_output') fls = gdir.read_pickle('inversion_flowlines') vs = [] for cl, fl in zip(cls, fls): vs.extend(cl['volume']) x, y = utils.tuple2int(fl.line.xy) thick[y, x] = cl['thick'] init_vol = np.sum(vs) # Interpolate xx, yy = gdir.grid.ij_coordinates pnan = np.nonzero(~np.isfinite(thick)) pok = np.nonzero(np.isfinite(thick)) points = np.array((np.ravel(yy[pok]), np.ravel(xx[pok]))).T inter = np.array((np.ravel(yy[pnan]), np.ravel(xx[pnan]))).T thick[pnan] = griddata(points, np.ravel(thick[pok]), inter, method='cubic') thick = thick.clip(0) # Slope thick *= slope_factor # Smooth dx = gdir.grid.dx if smooth_radius != 0: if smooth_radius is None: smooth_radius = np.rint(cfg.PARAMS['smooth_window'] / dx) thick = gaussian_blur(thick, np.int(smooth_radius)) thick = np.where(glacier_mask, thick, 0.) # Re-mask thick[glacier_mask == 0] = np.NaN assert np.all(np.isfinite(thick[glacier_mask == 1])) # Conserve volume tmp_vol = np.nansum(thick * dx**2) thick *= init_vol / tmp_vol # write grids_file = gdir.get_filepath('gridded_data') with utils.ncDataset(grids_file, 'a') as nc: vn = 'distributed_thickness' + varname_suffix if vn in nc.variables: v = nc.variables[vn] else: v = nc.createVariable(vn, 'f4', ( 'y', 'x', ), zlib=True) v.units = '-' v.long_name = 'Distributed ice thickness' v[:] = thick return thick
def distribute_thickness_interp(gdir, add_slope=True, smooth_radius=None, varname_suffix=''): """Compute a thickness map by interpolating between centerlines and border. This is a rather cosmetic task, not relevant for OGGM but for ITMIX. Parameters ---------- gdir : :py:class:`oggm.GlacierDirectory` the glacier directory to process add_slope : bool whether a corrective slope factor should be used or not smooth_radius : int pixel size of the gaussian smoothing. Default is to use cfg.PARAMS['smooth_window'] (i.e. a size in meters). Set to zero to suppress smoothing. varname_suffix : str add a suffix to the variable written in the file (for experiments) """ # Variables grids_file = gdir.get_filepath('gridded_data') # See if we have the masks, else compute them with utils.ncDataset(grids_file) as nc: has_masks = 'glacier_ext_erosion' in nc.variables if not has_masks: from oggm.core.gis import interpolation_masks interpolation_masks(gdir) with utils.ncDataset(grids_file) as nc: glacier_mask = nc.variables['glacier_mask'][:] glacier_ext = nc.variables['glacier_ext_erosion'][:] ice_divides = nc.variables['ice_divides'][:] if add_slope: slope_factor = nc.variables['slope_factor'][:] else: slope_factor = 1. # Thickness to interpolate thick = glacier_ext * np.NaN thick[(glacier_ext-ice_divides) == 1] = 0. # TODO: domain border too, for convenience for a start thick[0, :] = 0. thick[-1, :] = 0. thick[:, 0] = 0. thick[:, -1] = 0. # Along the lines cls = gdir.read_pickle('inversion_output') fls = gdir.read_pickle('inversion_flowlines') vs = [] for cl, fl in zip(cls, fls): vs.extend(cl['volume']) x, y = utils.tuple2int(fl.line.xy) thick[y, x] = cl['thick'] init_vol = np.sum(vs) # Interpolate xx, yy = gdir.grid.ij_coordinates pnan = np.nonzero(~ np.isfinite(thick)) pok = np.nonzero(np.isfinite(thick)) points = np.array((np.ravel(yy[pok]), np.ravel(xx[pok]))).T inter = np.array((np.ravel(yy[pnan]), np.ravel(xx[pnan]))).T thick[pnan] = griddata(points, np.ravel(thick[pok]), inter, method='cubic') thick = thick.clip(0) # Slope thick *= slope_factor # Smooth dx = gdir.grid.dx if smooth_radius != 0: if smooth_radius is None: smooth_radius = np.rint(cfg.PARAMS['smooth_window'] / dx) thick = gaussian_blur(thick, np.int(smooth_radius)) thick = np.where(glacier_mask, thick, 0.) # Re-mask thick[glacier_mask == 0] = np.NaN assert np.all(np.isfinite(thick[glacier_mask == 1])) # Conserve volume tmp_vol = np.nansum(thick * dx**2) thick *= init_vol / tmp_vol # write grids_file = gdir.get_filepath('gridded_data') with utils.ncDataset(grids_file, 'a') as nc: vn = 'distributed_thickness' + varname_suffix if vn in nc.variables: v = nc.variables[vn] else: v = nc.createVariable(vn, 'f4', ('y', 'x', ), zlib=True) v.units = '-' v.long_name = 'Distributed ice thickness' v[:] = thick return thick
def distribute_thickness_per_altitude(gdir, add_slope=True, smooth_radius=None, dis_from_border_exp=0.25, varname_suffix=''): """Compute a thickness map by redistributing mass along altitudinal bands. This is a rather cosmetic task, not relevant for OGGM but for ITMIX. Parameters ---------- gdir : oggm.GlacierDirectory the glacier directory to process add_slope : bool whether a corrective slope factor should be used or not smooth_radius : int pixel size of the gaussian smoothing. Default is to use cfg.PARAMS['smooth_window'] (i.e. a size in meters). Set to zero to suppress smoothing. dis_from_border_exp : float the exponent of the distance from border mask varname_suffix : str add a suffix to the variable written in the file (for experiments) """ # Variables grids_file = gdir.get_filepath('gridded_data') # See if we have the masks, else compute them with utils.ncDataset(grids_file) as nc: has_masks = 'glacier_ext_erosion' in nc.variables if not has_masks: from oggm.core.gis import interpolation_masks interpolation_masks(gdir) with utils.ncDataset(grids_file) as nc: topo_smoothed = nc.variables['topo_smoothed'][:] glacier_mask = nc.variables['glacier_mask'][:] dis_from_border = nc.variables['dis_from_border'][:] if add_slope: slope_factor = nc.variables['slope_factor'][:] else: slope_factor = 1. # Along the lines cls = gdir.read_pickle('inversion_output') fls = gdir.read_pickle('inversion_flowlines') hs, ts, vs, xs, ys = [], [], [], [], [] for cl, fl in zip(cls, fls): hs = np.append(hs, fl.surface_h) ts = np.append(ts, cl['thick']) vs = np.append(vs, cl['volume']) x, y = fl.line.xy xs = np.append(xs, x) ys = np.append(ys, y) init_vol = np.sum(vs) # Assign a first order thickness to the points # very inefficient inverse distance stuff thick = glacier_mask * np.NaN for y in range(thick.shape[0]): for x in range(thick.shape[1]): phgt = topo_smoothed[y, x] # take the ones in a 100m range starth = 100. while True: starth += 10 pok = np.nonzero(np.abs(phgt - hs) <= starth)[0] if len(pok) != 0: break sqr = np.sqrt((xs[pok] - x)**2 + (ys[pok] - y)**2) pzero = np.where(sqr == 0) if len(pzero[0]) == 0: thick[y, x] = np.average(ts[pok], weights=1 / sqr) elif len(pzero[0]) == 1: thick[y, x] = ts[pzero] else: raise RuntimeError('We should not be there') # Distance from border (normalized) dis_from_border = dis_from_border**dis_from_border_exp dis_from_border /= np.mean(dis_from_border[glacier_mask == 1]) thick *= dis_from_border # Slope thick *= slope_factor # Smooth dx = gdir.grid.dx if smooth_radius != 0: if smooth_radius is None: smooth_radius = np.rint(cfg.PARAMS['smooth_window'] / dx) thick = gaussian_blur(thick, np.int(smooth_radius)) thick = np.where(glacier_mask, thick, 0.) # Re-mask thick = thick.clip(0) thick[glacier_mask == 0] = np.NaN assert np.all(np.isfinite(thick[glacier_mask == 1])) # Conserve volume tmp_vol = np.nansum(thick * dx**2) thick *= init_vol / tmp_vol # write with utils.ncDataset(grids_file, 'a') as nc: vn = 'distributed_thickness' + varname_suffix if vn in nc.variables: v = nc.variables[vn] else: v = nc.createVariable(vn, 'f4', ( 'y', 'x', ), zlib=True) v.units = '-' v.long_name = 'Distributed ice thickness' v[:] = thick return thick
def distribute_thickness_per_altitude(gdir, add_slope=True, smooth_radius=None, dis_from_border_exp=0.25, varname_suffix=''): """Compute a thickness map by redistributing mass along altitudinal bands. This is a rather cosmetic task, not relevant for OGGM but for ITMIX. Parameters ---------- gdir : :py:class:`oggm.GlacierDirectory` the glacier directory to process add_slope : bool whether a corrective slope factor should be used or not smooth_radius : int pixel size of the gaussian smoothing. Default is to use cfg.PARAMS['smooth_window'] (i.e. a size in meters). Set to zero to suppress smoothing. dis_from_border_exp : float the exponent of the distance from border mask varname_suffix : str add a suffix to the variable written in the file (for experiments) """ # Variables grids_file = gdir.get_filepath('gridded_data') # See if we have the masks, else compute them with utils.ncDataset(grids_file) as nc: has_masks = 'glacier_ext_erosion' in nc.variables if not has_masks: from oggm.core.gis import interpolation_masks interpolation_masks(gdir) with utils.ncDataset(grids_file) as nc: topo_smoothed = nc.variables['topo_smoothed'][:] glacier_mask = nc.variables['glacier_mask'][:] dis_from_border = nc.variables['dis_from_border'][:] if add_slope: slope_factor = nc.variables['slope_factor'][:] else: slope_factor = 1. # Along the lines cls = gdir.read_pickle('inversion_output') fls = gdir.read_pickle('inversion_flowlines') hs, ts, vs, xs, ys = [], [], [], [], [] for cl, fl in zip(cls, fls): hs = np.append(hs, fl.surface_h) ts = np.append(ts, cl['thick']) vs = np.append(vs, cl['volume']) x, y = fl.line.xy xs = np.append(xs, x) ys = np.append(ys, y) init_vol = np.sum(vs) # Assign a first order thickness to the points # very inefficient inverse distance stuff thick = glacier_mask * np.NaN for y in range(thick.shape[0]): for x in range(thick.shape[1]): phgt = topo_smoothed[y, x] # take the ones in a 100m range starth = 100. while True: starth += 10 pok = np.nonzero(np.abs(phgt - hs) <= starth)[0] if len(pok) != 0: break sqr = np.sqrt((xs[pok]-x)**2 + (ys[pok]-y)**2) pzero = np.where(sqr == 0) if len(pzero[0]) == 0: thick[y, x] = np.average(ts[pok], weights=1 / sqr) elif len(pzero[0]) == 1: thick[y, x] = ts[pzero] else: raise RuntimeError('We should not be there') # Distance from border (normalized) dis_from_border = dis_from_border**dis_from_border_exp dis_from_border /= np.mean(dis_from_border[glacier_mask == 1]) thick *= dis_from_border # Slope thick *= slope_factor # Smooth dx = gdir.grid.dx if smooth_radius != 0: if smooth_radius is None: smooth_radius = np.rint(cfg.PARAMS['smooth_window'] / dx) thick = gaussian_blur(thick, np.int(smooth_radius)) thick = np.where(glacier_mask, thick, 0.) # Re-mask thick = thick.clip(0) thick[glacier_mask == 0] = np.NaN assert np.all(np.isfinite(thick[glacier_mask == 1])) # Conserve volume tmp_vol = np.nansum(thick * dx**2) thick *= init_vol / tmp_vol # write with utils.ncDataset(grids_file, 'a') as nc: vn = 'distributed_thickness' + varname_suffix if vn in nc.variables: v = nc.variables[vn] else: v = nc.createVariable(vn, 'f4', ('y', 'x', ), zlib=True) v.units = '-' v.long_name = 'Distributed ice thickness' v[:] = thick return thick