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Module oggm_shop

This IGM module utilizes OGGM utilities and the GlaThiDa dataset to prepare data for the IGM model for a specific glacier given its RGI ID (parameter RGI_ID). You can check the GLIMS Viewer to find the RGI ID of your glacier. By default, IGM references RGI 7.0C, which can be found here. Altering the RGI_product parameter ('C' for glacier complex or 'G' for individual glacier) allows you to switch between these options. By default, data is preprocessed (preprocess parameter is set to True) with a spatial resolution of 100 meters and a border size of 30 meters. To customize the spatial resolution and the size of the 'border' to maintain a safe distance from the glacier margin, you need to set the preprocess parameter to False, and then set the dx and border parameters as desired. However, unless one already has experience with the OGGM workflow and installation process, we advise that preprocess remains True, as turning it off requires one to subsequently recreate much of this process.

When this module is executed, it automatically downloads a suite of data (refer to the table below) associated with the specified glacier (individual or complex). These data are stored in a directory named after the RGI ID within the data folder. Subsequently, a file named input.nc is created, containing the relevant variables renamed according to IGM's naming conventions.

Important: The oggm_shop module must be followed by the local inputs module, which reads data/input.nc and loads the 2D gridded variables as TensorFlow objects in IGM.

If IGM is run a second time, it will not re-download the OGGM data or recreate data/input.nc as long as the data remain in the data folder. This is particularly useful for parameter analysis, as it avoids redundant data downloads during multiple runs. However, note that, if you subsequently download a second glacier and input.nc already exists in the folder, it will not be overwritten. Also note that the default operation is for the downloaded data to be deleted once input.nc is written; set the parameter remove_RGI_folder to False to disable this. The oggm_shop module provides all the necessary data variables required to run IGM for forward glacier evolution simulations, assuming the availability of basal topography (topg) and ice thickness (thk).

Additionally, it supports preliminary data assimilation and inverse modeling tasks within the iceflow module. These tasks typically involve variables such as icemaskobs, thkinit, uvelsurf, vvelsurf, thkobs, and usurfobs.

Data available via the shop are listed in the table below. Users can specify the source for ice thickness using the thk_source parameter (options: millan_ice_thickness or consensus_ice_thickness dataset) and for ice velocities using the vel_source parameter (options: millan_ice_velocity or its_live dataset).

Set include_glathida to True to retrieve the GlaThiDa ice thickness profiles for data assimilation purpose. For RGI 6.0 and 7.0, GlaThiDa data specific to the glacier, identified by its RGI ID, are retrieved from the OGGM server. These data are saved as a text file named glathida_data.csv in the module's download directory. In both cases, the data are read, rasterized with the label thkobs, and any pixels lacking observations are marked with NaN values.

Variable Reference
Surface DEM Copernicus DEM GLO-90
Ice thickness Millan et al. (2022)
Ice thickness Farinotti et al. (2019)
Ice thickness profile GlaThiDa
Surface ice speeds Millan et al. (2022)
Surface ice speeds its-live.jpl.nasa.gov
Glacier mask Randolph Glacier Inventory
Surface height change Hugonnet et al. (2021)
Climate data GSWP3_W5E5
Flowline OGGM

Table: Products available with the oggm_shop module.

The module depends (of course) on the oggm library. Unfortunately the module works on Linux and macOS, but not on Windows (unless using WSL).

Contributors: F. Maussion, G. Jouvet, E. Welty (GlaThiDa-related code), S. Cook (RGI 7.0 modifications).

Parameters

Default configuration file (oggm_shop.yaml): 

oggm_shop:
  RGI_ID: "RGI2000-v7.0-C-11-01323"
  RGI_IDs: ["RGI2000-v7.0-C-11-01323"]
  preprocess: True
  dx: 100.0
  border: 30
  thk_source: consensus_ice_thickness
  vel_source: millan_ice_velocity
  incl_glathida: False
  filename: input.nc
  remove_RGI_folder: False
  sub_entity_mask: False
  smooth_obs_vel: True
  highres: False
  OGGM_server_v7: "https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/exps/igm_v4"
  OGGM_server_v7_hr: "https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/exps/igm_v4_hr"
  OGGM_server_v6: "https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/exps/igm_v5_era5/"

Description of the parameters:

Name Description Default value Units
RGI_ID RGI ID of the selected glacier, G stands for individual Glacier, and C for glacier Complex for RGI7. RGI2000-v7.0-C-11-01323 —
RGI_IDs List of RGI IDs of the selected glaciers, G stands for individual Glacier, and C for glacier Complex for RGI7. ['RGI2000-v7.0-C-11-01323'] —
preprocess Use OGGM preprocessing if you are fine with given spatial resolution and border size. True —
dx Spatial resolution (need preprocess false to change it). 100.0 m
border Safe border margin, number of pixels, (need preprocess false to change it). 30 —
thk_source Millan ice thickness (millan_ice_thickness) or consensus ice thickness (consensus_ice_thickness). consensus_ice_thickness —
vel_source Source of the surface velocities (millan_ice_velocity or its_live). millan_ice_velocity —
incl_glathida Set this to True for retrieving the GlaThiDa ice thickness profiles for the inversion. False —
filename NetCDF input data file created by OGGM. input.nc —
remove_RGI_folder Remove the RGI folder once input.nc is built. Keep False if other modules read it (e.g. climate or smb with method oggm). False —
sub_entity_mask Ice mask shows individual RGI 7.0G entities within each larger RGI 7.0C complex. Also produces a mask of glaciers with tidewater termini (RGI7.0C or G only) False —
smooth_obs_vel Smooth the observed velocities. True —
highres Use high resolution data. False —
OGGM_server_v7 The address of the OGGM server for RGI7.0 directories (if highres = False) https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/exps/igm_v4 —
OGGM_server_v7_hr The address of the OGGM server for RGI7.0 high-resolution directories (if highres = True) https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/exps/igm_v4_hr —
OGGM_server_v6 The address of the OGGM server for RGI6.0 directories. https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/exps/igm_v5_era5/ —