Step-by-Step guide to rebuilding the preprocessed directories from scratch

Step-by-Step guide to rebuilding the preprocessed directories from scratch#

This guide is for anyone who wants to learn how to start from scratch with the preprocessed directories of OGGM. You might even use your own data. This tutorial assumes you are already familiar with OGGM basics. We won’t go into every little detail here, but you’ll find links for more information if you’re interested.

We’ve structured the guide into five main sections, each dedicated to a different level of preprocessing. At the beginning of each section, we’ll outline the tasks to be performed, the data we’ll use, and provide links to related tutorials. Additionally, at the end of each section, we’ll share a corresponding prepro_base_url. This URL allows you to start directly at that level with everything pre-setup, bypassing the need to complete the earlier steps. Plus, in the tutorial store_and_compress_glacierdirs, we show you how to save your work. This way, you don’t have to redo everything from the beginning every time (many steps only need to be done once).

Tip: There’s a lot to learn here. If you’re curious about a specific function and want to know more, just add a question mark (?) right after it, and you’ll see more details.

# Example: Getting help on the Python function 'print'
print?

Tags: advanced, glacier-directory, workflow

Set-up#

First, let’s get everything ready to go. Here’s how we’ll do it:

Import Functions: We’ll start by importing the functions we need. Depending on which preprocessed level you’re working with, you might not need all of them.
Initialize OGGM: Next, we’ll set up OGGM and choose where we want to save our work (defining the working directory).
Choose a Glacier: Lastly, we’ll pick one glacier to focus on as our example.

Remember, these steps are important no matter which level you’re starting from!

from oggm import cfg, utils, workflow, tasks, DEFAULT_BASE_URL

import geopandas as gpd
import numpy as np
import os

# we always need to initialzie and define a working directory
cfg.initialize(logging_level='WARNING')
cfg.PATHS['working_dir'] = utils.gettempdir(dirname='OGGM-full_prepro_elevation_bands', reset=True)

2024-04-25 13:51:36: oggm.cfg: Reading default parameters from the OGGM `params.cfg` configuration file.
2024-04-25 13:51:36: oggm.cfg: Multiprocessing switched OFF according to the parameter file.
2024-04-25 13:51:36: oggm.cfg: Multiprocessing: using all available processors (N=4)

# Our example glacier
rgi_ids = ['RGI60-11.00897']  # Hintereisferner
rgi_region = '11'  # this must fit to example glacier(s), if starting from level 0

# This section is only for future developments of the tutorial (e.g. updateing for new OGGM releases)
# Test if prepro_base_url valid for both flowline_type_to_use, see level 2.
# In total four complete executions of the notebook:
# (load_from_prepro_base_url=False/True and flowline_type_to_use = 'elevation_band'/'centerline')
load_from_prepro_base_url = False

Level 0#

Tasks:

Define the rgi_id for your glacier directory gdir.
Define the map projection of the glacier directory
Add an outline of the glacier.
Optionally add intersects to other outlines.

Data used:

Glacier outline
Optionally intersects

Related Tutorials:

working_with_rgi will show you how to read glacier outline files and prepare them for a run
use_your_own_inventory: Use custom glacier inventories with OGGM

CAUTION: When using your own glacier outlines, it's important to note that OGGM relies on the defined RGI_ID to fetch calibration data from global datasets, which are tailored to the RGI outlines. If your glacier's outline significantly deviates from its RGI counterpart, this could introduce errors, potentially large or small, into your model's results. Ideally, you should provide your own calibration data for custom outlines or, at the very least, be mindful of the discrepancies this might cause.

# load all RGI outlines for our region and extract the example glaciers
rgidf = gpd.read_file(utils.get_rgi_region_file(rgi_region, version='62'))
rgidf = rgidf[np.isin(rgidf.RGIId, rgi_ids)]

# set the used projection used for gdir, options 'tmerc' or 'utm'
cfg.PARAMS['map_proj'] = cfg.PARAMS['map_proj']  # default is 'tmerc'

gdirs = workflow.init_glacier_directories(rgidf, reset=True, force=True)

2024-04-25 13:51:39: oggm.workflow: Execute entity tasks [GlacierDirectory] on 1 glaciers

# Instruction for beginning with existing OGGM's preprocessed directories
if load_from_prepro_base_url:
    # to start from level 0 you can do
    prepro_base_url_L0 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L1-L2_files/elev_bands/'
    gdirs = workflow.init_glacier_directories(rgi_ids,
                                              from_prepro_level=0,
                                              prepro_base_url=prepro_base_url_L0,
                                              prepro_border=80,  # could be 10, 80, 160 or 240
                                              reset=True,
                                              force=True,
                                             )

Level 1#

Tasks:

Define the border around the outline.
Define the local grid resolution, which will also set the resolution for the flowlines.
Add the digital elevation model DEM.
Set up a local grid for each gdir.

Data used:

DEM file

Related Tutorials:

dem_sources: Create local topography maps from different DEM sources with OGGM
rgitopo_rgi6: RGI-TOPO for RGI v6.0

Please note that registration may be required to access some of the DEM sources. For more information, refer to the dem_sources tutorial.

# define the border, we keep the default here
cfg.PARAMS['border'] = cfg.PARAMS['border']

# set the method for determining the local grid resolution
cfg.PARAMS['grid_dx_method'] = cfg.PARAMS['grid_dx_method']  # The default method is 'square', which determines the grid spacing (dx) based on the glacier's outline area.
cfg.PARAMS['fixed_dx'] = cfg.PARAMS['fixed_dx']  # This allows setting a specific resolution in meters. It's applicable only when grid_dx_method is set to 'fixed'.

# set the DEM source to use
source = None  # we stick with the OGGM default

# this task adds the DEM and defines the local grid
workflow.execute_entity_task(tasks.define_glacier_region, gdirs,
                             source=source);

2024-04-25 13:51:39: oggm.workflow: Execute entity tasks [define_glacier_region] on 1 glaciers
2024-04-25 13:51:40: oggm.core.gis: HttpDownloadError occurred during task define_glacier_region on RGI60-11.00897: (401, 'https://e4ftl01.cr.usgs.gov/MEASURES/NASADEM_HGT.001/2000.02.11/NASADEM_HGT_n46e010.zip')

---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:538, in _progress_urlretrieve(url, cache_name, reset, auth, timeout)
    537 try:
--> 538     from progressbar import DataTransferBar, UnknownLength
    539     pbar = None

ModuleNotFoundError: No module named 'progressbar'

During handling of the above exception, another exception occurred:

HttpDownloadError                         Traceback (most recent call last)
Cell In[8], line 12
      9 source = None  # we stick with the OGGM default
     11 # this task adds the DEM and defines the local grid
---> 12 workflow.execute_entity_task(tasks.define_glacier_region, gdirs,
     13                              source=source);

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in execute_entity_task(task, gdirs, **kwargs)
    188     if ng > 3:
    189         log.workflow('WARNING: you are trying to run an entity task on '
    190                      '%d glaciers with multiprocessing turned off. OGGM '
    191                      'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
    194 return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in <listcomp>(.0)
    188     if ng > 3:
    189         log.workflow('WARNING: you are trying to run an entity task on '
    190                      '%d glaciers with multiprocessing turned off. OGGM '
    191                      'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
    194 return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:109, in _pickle_copier.__call__(self, arg)
    107 for func in self.call_func:
    108     func, kwargs = func
--> 109     res = self._call_internal(func, arg, kwargs)
    110 return res

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:103, in _pickle_copier._call_internal(self, call_func, gdir, kwargs)
    100     gdir, gdir_kwargs = gdir
    101     kwargs.update(gdir_kwargs)
--> 103 return call_func(gdir, **kwargs)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:492, in entity_task.__call__.<locals>._entity_task(gdir, reset, print_log, return_value, continue_on_error, add_to_log_file, **kwargs)
    490     signal.alarm(cfg.PARAMS['task_timeout'])
    491 ex_t = time.time()
--> 492 out = task_func(gdir, **kwargs)
    493 ex_t = time.time() - ex_t
    494 if cfg.PARAMS['task_timeout'] > 0:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/gis.py:550, in define_glacier_region(gdir, entity, source)
    546 # Back to lon, lat for DEM download/preparation
    547 tmp_grid = salem.Grid(proj=utm_proj, nxny=(nx, ny), x0y0=(ulx, uly),
    548                       dxdy=(dx, -dx), pixel_ref='corner')
--> 550 dem_list, dem_source = get_dem_for_grid(grid=tmp_grid,
    551                                         fpath=gdir.get_filepath('dem'),
    552                                         source=source, gdir=gdir)
    554 # Glacier grid
    555 x0y0 = (ulx+dx/2, uly-dx/2)  # To pixel center coordinates

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/gis.py:482, in get_dem_for_grid(grid, fpath, source, gdir)
    471 grid_prop = {
    472     'utm_proj': grid.proj,
    473     'dx': grid.dx,
   (...)
    477     'ny': grid.ny
    478 }
    480 source = check_dem_source(source, extent_ll, rgi_id=rgi_id)
--> 482 dem_list, dem_source = get_topo_file((minlon, maxlon), (minlat, maxlat),
    483                                      gdir=gdir,
    484                                      dx_meter=grid_prop['dx'],
    485                                      source=source)
    487 if rgi_id is not None:
    488     log.debug('(%s) DEM source: %s', rgi_id, dem_source)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:2487, in get_topo_file(lon_ex, lat_ex, gdir, dx_meter, zoom, source)
   2485     zones = nasadem_zone(lon_ex, lat_ex)
   2486     for z in zones:
-> 2487         files.append(_download_nasadem_file(z))
   2489 # filter for None (e.g. oceans)
   2490 files = [s for s in files if s]

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:895, in _download_nasadem_file(zone)
    893 def _download_nasadem_file(zone):
    894     with get_lock():
--> 895         return _download_nasadem_file_unlocked(zone)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:915, in _download_nasadem_file_unlocked(zone)
    912     return outpath
    914 # Did we download it yet?
--> 915 dest_file = file_downloader(wwwfile)
    917 # None means we tried hard but we couldn't find it
    918 if not dest_file:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:606, in file_downloader(www_path, retry_max, sleep_on_retry, cache_name, reset, auth, timeout)
    604 try:
    605     retry_counter += 1
--> 606     local_path = _progress_urlretrieve(www_path, cache_name=cache_name,
    607                                        reset=reset, auth=auth,
    608                                        timeout=timeout)
    609     # if no error, exit
    610     break

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:562, in _progress_urlretrieve(url, cache_name, reset, auth, timeout)
    560     return res
    561 except ImportError:
--> 562     return oggm_urlretrieve(url, cache_obj_name=cache_name,
    563                             reset=reset, auth=auth, timeout=timeout)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:530, in oggm_urlretrieve(url, cache_obj_name, reset, reporthook, auth, timeout)
    526             _classic_urlretrieve(url, cache_path, reporthook, auth,
    527                                  timeout)
    528     return cache_path
--> 530 return _verified_download_helper(cache_obj_name, _dlf, reset)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:336, in _verified_download_helper(cache_obj_name, dl_func, reset)
    329 def _verified_download_helper(cache_obj_name, dl_func, reset=False):
    330     """Helper function for downloads.
    331 
    332     Verifies the size and hash of the downloaded file against the included
    333     list of known static files.
    334     Uses _cached_download_helper to perform the actual download.
    335     """
--> 336     path = _cached_download_helper(cache_obj_name, dl_func, reset)
    338     dl_verify = cfg.PARAMS.get('dl_verify', False)
    340     if dl_verify and path and cache_obj_name not in cfg.DL_VERIFIED:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:320, in _cached_download_helper(cache_obj_name, dl_func, reset)
    317 mkdir(os.path.dirname(cache_path))
    319 try:
--> 320     cache_path = _call_dl_func(dl_func, cache_path)
    321 except BaseException:
    322     if os.path.exists(cache_path):

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:262, in _call_dl_func(dl_func, cache_path)
    259 def _call_dl_func(dl_func, cache_path):
    260     """Helper so the actual call to downloads can be overridden
    261     """
--> 262     return dl_func(cache_path)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:521, in oggm_urlretrieve.<locals>._dlf(cache_path)
    519 logger.info("Downloading %s to %s..." % (url, cache_path))
    520 try:
--> 521     _requests_urlretrieve(url, cache_path, reporthook, auth, timeout)
    522 except requests.exceptions.InvalidSchema:
    523     if 'ftps://' in url:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_downloads.py:376, in _requests_urlretrieve(url, path, reporthook, auth, timeout)
    374 with requests.get(url, stream=True, auth=auth, timeout=timeout) as r:
    375     if r.status_code != 200:
--> 376         raise HttpDownloadError(r.status_code, url)
    377     r.raise_for_status()
    379     size = r.headers.get('content-length') or -1

HttpDownloadError: (401, 'https://e4ftl01.cr.usgs.gov/MEASURES/NASADEM_HGT.001/2000.02.11/NASADEM_HGT_n46e010.zip')

# Instruction for beginning with existing OGGM's preprocessed directories
if load_from_prepro_base_url:
    # to start from level 1 you can do
    prepro_base_url_L1 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L1-L2_files/elev_bands/'
    gdirs = workflow.init_glacier_directories(rgi_ids,
                                              from_prepro_level=1,
                                              prepro_base_url=prepro_base_url_L1,
                                              prepro_border=80,  # could be 10, 80, 160 or 240
                                              reset=True,
                                              force=True,
                                             )

Level 2#

Tasks:

Choose the type of flowline to use.
Create the flowlines surface structure, including surface height and width.
Create the downstream flowline, which starts from the glacier’s terminus and extends downstream.
Optionally you can bring in extra data from the OGGM-shop and bin it to the elevation band flowline.

Data used:

Outline
DEM
Optional: additional datasets

Related Tutorials:

elevation_bands_vs_centerlines: Differences between “elevation band” and “centerline” flowlines
numeric_solvers: Understand the difference between the ice dynamic solvers in OGGM
oggm_shop: OGGM-Shop and Glacier Directories in OGGM
ingest_gridded_data_on_flowlines: ingest gridded products such as ice velocity into OGGM (and compare them with model output)

Starting from this point, it's important to choose the prepro_base_url based on the type of flowline you're working with (see end of this chapter).

flowline_type_to_use = 'elevation_band'  # you can also select 'centerline' here

if flowline_type_to_use == 'elevation_band':
    elevation_band_task_list = [
        tasks.simple_glacier_masks,
        tasks.elevation_band_flowline,
        tasks.fixed_dx_elevation_band_flowline,
        tasks.compute_downstream_line,
        tasks.compute_downstream_bedshape,
    ]

    for task in elevation_band_task_list:
        workflow.execute_entity_task(task, gdirs);

elif flowline_type_to_use == 'centerline':
    # for centerline we can use parabola downstream line
    cfg.PARAMS['downstream_line_shape'] = 'parabola'

    centerline_task_list = [
        tasks.glacier_masks,
        tasks.compute_centerlines,
        tasks.initialize_flowlines,
        tasks.catchment_area,
        tasks.catchment_intersections,
        tasks.catchment_width_geom,
        tasks.catchment_width_correction,
        tasks.compute_downstream_line,
        tasks.compute_downstream_bedshape,
    ]

    for task in centerline_task_list:
        workflow.execute_entity_task(task, gdirs);
    
else:
    raise ValueError(f"Unknown flowline type '{flowline_type_to_use}'! Select 'elevation_band' or 'centerline'!")

2024-04-25 13:51:41: oggm.workflow: Execute entity tasks [simple_glacier_masks] on 1 glaciers
2024-04-25 13:51:41: oggm.core.gis: RasterioIOError occurred during task process_dem on RGI60-11.00897: /tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/dem.tif: No such file or directory
2024-04-25 13:51:41: oggm.core.gis: RasterioIOError occurred during task simple_glacier_masks on RGI60-11.00897: /tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/dem.tif: No such file or directory

---------------------------------------------------------------------------
CPLE_OpenFailedError                      Traceback (most recent call last)
File rasterio/_base.pyx:310, in rasterio._base.DatasetBase.__init__()

File rasterio/_base.pyx:221, in rasterio._base.open_dataset()

File rasterio/_err.pyx:221, in rasterio._err.exc_wrap_pointer()

CPLE_OpenFailedError: /tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/dem.tif: No such file or directory

During handling of the above exception, another exception occurred:

RasterioIOError                           Traceback (most recent call last)
Cell In[10], line 13
      4     elevation_band_task_list = [
      5         tasks.simple_glacier_masks,
      6         tasks.elevation_band_flowline,
   (...)
      9         tasks.compute_downstream_bedshape,
     10     ]
     12     for task in elevation_band_task_list:
---> 13         workflow.execute_entity_task(task, gdirs);
     15 elif flowline_type_to_use == 'centerline':
     16     # for centerline we can use parabola downstream line
     17     cfg.PARAMS['downstream_line_shape'] = 'parabola'

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in execute_entity_task(task, gdirs, **kwargs)
    188     if ng > 3:
    189         log.workflow('WARNING: you are trying to run an entity task on '
    190                      '%d glaciers with multiprocessing turned off. OGGM '
    191                      'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
    194 return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in <listcomp>(.0)
    188     if ng > 3:
    189         log.workflow('WARNING: you are trying to run an entity task on '
    190                      '%d glaciers with multiprocessing turned off. OGGM '
    191                      'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
    194 return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:109, in _pickle_copier.__call__(self, arg)
    107 for func in self.call_func:
    108     func, kwargs = func
--> 109     res = self._call_internal(func, arg, kwargs)
    110 return res

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:103, in _pickle_copier._call_internal(self, call_func, gdir, kwargs)
    100     gdir, gdir_kwargs = gdir
    101     kwargs.update(gdir_kwargs)
--> 103 return call_func(gdir, **kwargs)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:492, in entity_task.__call__.<locals>._entity_task(gdir, reset, print_log, return_value, continue_on_error, add_to_log_file, **kwargs)
    490     signal.alarm(cfg.PARAMS['task_timeout'])
    491 ex_t = time.time()
--> 492 out = task_func(gdir, **kwargs)
    493 ex_t = time.time() - ex_t
    494 if cfg.PARAMS['task_timeout'] > 0:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/gis.py:1032, in simple_glacier_masks(gdir)
   1027     raise GeometryError('{} is a nominal glacier.'.format(gdir.rgi_id))
   1029 if not os.path.exists(gdir.get_filepath('gridded_data')):
   1030     # In a possible future, we might actually want to raise a
   1031     # deprecation warning here
-> 1032     process_dem(gdir)
   1034 # Geometries
   1035 geometry = gdir.read_shapefile('outlines').geometry[0]

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:492, in entity_task.__call__.<locals>._entity_task(gdir, reset, print_log, return_value, continue_on_error, add_to_log_file, **kwargs)
    490     signal.alarm(cfg.PARAMS['task_timeout'])
    491 ex_t = time.time()
--> 492 out = task_func(gdir, **kwargs)
    493 ex_t = time.time() - ex_t
    494 if cfg.PARAMS['task_timeout'] > 0:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/gis.py:764, in process_dem(gdir, grid, fpath, output_filename)
    747 """Reads the DEM from the tiff, attempts to fill voids and apply smooth.
    748 
    749 The data is then written to `gridded_data.nc`.
   (...)
    760     The filename of the nc file to add the DEM to. Defaults to gridded_data
    761 """
    762 if gdir is not None:
    763     # open srtm tif-file:
--> 764     dem = read_geotiff_dem(gdir)
    765     # Grid
    766     dem_grid = gdir.grid

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/gis.py:654, in read_geotiff_dem(gdir, fpath)
    650     else:
    651         raise InvalidParamsError('If you do not provide a gdir you must'
    652                                  f'define a fpath! Given fpath={fpath}.')
--> 654 with rasterio.open(dem_path, 'r', driver='GTiff') as ds:
    655     topo = ds.read(1).astype(rasterio.float32)
    656     topo[topo <= -999.] = np.NaN

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/rasterio/env.py:451, in ensure_env_with_credentials.<locals>.wrapper(*args, **kwds)
    448     session = DummySession()
    450 with env_ctor(session=session):
--> 451     return f(*args, **kwds)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/rasterio/__init__.py:304, in open(fp, mode, driver, width, height, count, crs, transform, dtype, nodata, sharing, **kwargs)
    301 path = _parse_path(raw_dataset_path)
    303 if mode == "r":
--> 304     dataset = DatasetReader(path, driver=driver, sharing=sharing, **kwargs)
    305 elif mode == "r+":
    306     dataset = get_writer_for_path(path, driver=driver)(
    307         path, mode, driver=driver, sharing=sharing, **kwargs
    308     )

File rasterio/_base.pyx:312, in rasterio._base.DatasetBase.__init__()

RasterioIOError: /tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/dem.tif: No such file or directory

# Instruction for beginning with existing OGGM's preprocessed directories
if load_from_prepro_base_url:
    # to start from level 2 we need to distinguish between the flowline types
    if flowline_type_to_use == 'elevation_band':
        prepro_base_url_L2 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L1-L2_files/2023.2/elev_bands_w_data/'
    elif flowline_type_to_use == 'centerline':
        prepro_base_url_L2 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L1-L2_files/centerlines/'
    else:
        raise ValueError(f"Unknown flowline type '{flowline_type_to_use}'! Select 'elevation_band' or 'centerline'!")

    gdirs = workflow.init_glacier_directories(rgi_ids,
                                              from_prepro_level=2,
                                              prepro_base_url=prepro_base_url_L2,
                                              prepro_border=80,  # could be 10, 80, 160 or 240
                                              reset=True,
                                              force=True,
                                             )

Level 3#

Tasks:

Add baseline climate data to gdir.
Calibrate the mass balance model statically (without considering glacier dynamics) using geodetic observations. This involves the calibration of melt_f, prcp_fac and temp_bias.
Conduct an inversion for the glacier’s bed topography. Including the calibration of glen_a and fs by matching to the total volume estimate.
Create the dynamic flowline for dynamic simulation runs.

Data used:

Climate data (default source: GSWP3_W5E5)
Geodetic mass balance observations (default source: Hugonnet al. 2021)
Volume estimate (default source: Farinotti et al. (2019))

Related Tutorials:

oggm_shop: OGGM-Shop and Glacier Directories in OGGM
massbalance_calibration: A look into the new mass balance calibration in OGGM v1.6
massbalance_perturbation: Mass balance parameter perturbation experiments
inversion: run the OGGM ice thickness inversion model with various ice parameters

For the inversion, we diverge from the standard preprocessed directories when focusing on individual glaciers instead of entire regions. This is because calibrate_inversion_from_consensus adjusts glacier volume based on total regional consensus estimates, not per glacier. Since volume estimates are model-based and not directly observed, they're less reliable for individual calibration. However, for our example, we'll calibrate using the consensus estimate for a single glacier, differing from the preprocessed approach.

# define the climate data to use, we keep the default
cfg.PARAMS['baseline_climate'] = cfg.PARAMS['baseline_climate']

# add climate data to gdir
workflow.execute_entity_task(tasks.process_climate_data, gdirs);

# the default mb calibration
workflow.execute_entity_task(tasks.mb_calibration_from_geodetic_mb,
                             gdirs,
                             informed_threestep=True,  # only available for 'GSWP3_W5E5'
                            );

# glacier bed inversion
workflow.execute_entity_task(tasks.apparent_mb_from_any_mb, gdirs);
workflow.calibrate_inversion_from_consensus(
    gdirs,
    apply_fs_on_mismatch=True,
    error_on_mismatch=True,  # if you running many glaciers some might not work
    filter_inversion_output=True,  # this partly filters the overdeepening due to
    # the equilibrium assumption for retreating glaciers (see. Figure 5 of Maussion et al. 2019)
    volume_m3_reference=None,  # here you could provide your own total volume estimate in m3
);

# finally create the dynamic flowlines
workflow.execute_entity_task(tasks.init_present_time_glacier, gdirs);

2024-04-25 13:51:41: oggm.workflow: Execute entity tasks [process_climate_data] on 1 glaciers
2024-04-25 13:51:42: oggm.workflow: Execute entity tasks [mb_calibration_from_geodetic_mb] on 1 glaciers
2024-04-25 13:51:42: oggm.core.massbalance: FileNotFoundError occurred during task mb_calibration_from_scalar_mb on RGI60-11.00897: [Errno 2] No such file or directory: '/tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/inversion_flowlines.pkl'
2024-04-25 13:51:42: oggm.core.massbalance: FileNotFoundError occurred during task mb_calibration_from_geodetic_mb on RGI60-11.00897: [Errno 2] No such file or directory: '/tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/inversion_flowlines.pkl'

---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
Cell In[12], line 8
workflow.execute_entity_task(tasks.process_climate_data, gdirs);
# the default mb calibration
----> 8 workflow.execute_entity_task(tasks.mb_calibration_from_geodetic_mb,
                            gdirs,
                            informed_threestep=True,  # only available for 'GSWP3_W5E5'
                           );
# glacier bed inversion
workflow.execute_entity_task(tasks.apparent_mb_from_any_mb, gdirs);

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in execute_entity_task(task, gdirs, **kwargs)
   if ng > 3:
       log.workflow('WARNING: you are trying to run an entity task on '
                    '%d glaciers with multiprocessing turned off. OGGM '
                    'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in <listcomp>(.0)
   if ng > 3:
       log.workflow('WARNING: you are trying to run an entity task on '
                    '%d glaciers with multiprocessing turned off. OGGM '
                    'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:109, in _pickle_copier.__call__(self, arg)
for func in self.call_func:
   func, kwargs = func
--> 109     res = self._call_internal(func, arg, kwargs)
return res

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:103, in _pickle_copier._call_internal(self, call_func, gdir, kwargs)
   gdir, gdir_kwargs = gdir
   kwargs.update(gdir_kwargs)
--> 103 return call_func(gdir, **kwargs)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:492, in entity_task.__call__.<locals>._entity_task(gdir, reset, print_log, return_value, continue_on_error, add_to_log_file, **kwargs)
   signal.alarm(cfg.PARAMS['task_timeout'])
ex_t = time.time()
--> 492 out = task_func(gdir, **kwargs)
ex_t = time.time() - ex_t
if cfg.PARAMS['task_timeout'] > 0:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/massbalance.py:1571, in mb_calibration_from_geodetic_mb(gdir, ref_period, write_to_gdir, overwrite_gdir, use_regional_avg, override_missing, informed_threestep, calibrate_param1, calibrate_param2, calibrate_param3, mb_model_class, filesuffix)
   prcp_fac_min = clip_scalar(prcp_fac * 0.8, mi, ma)
   prcp_fac_max = clip_scalar(prcp_fac * 1.2, mi, ma)
-> 1571     return mb_calibration_from_scalar_mb(gdir,
                                        ref_mb=ref_mb,
                                        ref_mb_err=ref_mb_err,
                                        ref_period=ref_period,
                                        write_to_gdir=write_to_gdir,
                                        overwrite_gdir=overwrite_gdir,
                                        calibrate_param1='prcp_fac',
                                        calibrate_param2='melt_f',
                                        calibrate_param3='temp_bias',
                                        prcp_fac=prcp_fac,
                                        prcp_fac_min=prcp_fac_min,
                                        prcp_fac_max=prcp_fac_max,
                                        temp_bias=temp_bias,
                                        mb_model_class=mb_model_class,
                                        filesuffix=filesuffix,
                                        )
else:
   return mb_calibration_from_scalar_mb(gdir,
                                        ref_mb=ref_mb,
                                        ref_mb_err=ref_mb_err,
   (...)
                                        filesuffix=filesuffix,
                                        )

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:492, in entity_task.__call__.<locals>._entity_task(gdir, reset, print_log, return_value, continue_on_error, add_to_log_file, **kwargs)
   signal.alarm(cfg.PARAMS['task_timeout'])
ex_t = time.time()
--> 492 out = task_func(gdir, **kwargs)
ex_t = time.time() - ex_t
if cfg.PARAMS['task_timeout'] > 0:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/massbalance.py:1744, in mb_calibration_from_scalar_mb(gdir, ref_mb, ref_mb_err, ref_period, ref_mb_years, write_to_gdir, overwrite_gdir, calibrate_param1, calibrate_param2, calibrate_param3, melt_f, melt_f_min, melt_f_max, prcp_fac, prcp_fac_min, prcp_fac_max, temp_bias, temp_bias_min, temp_bias_max, mb_model_class, filesuffix)
if ref_mb_years is not None and ref_period is not None:
   raise InvalidParamsError('Cannot set `ref_mb_years` and `ref_period` '
                            'at the same time.')
-> 1744 fls = gdir.read_pickle('inversion_flowlines')
# Let's go
# Climate period
if ref_mb_years is not None:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:3178, in GlacierDirectory.read_pickle(self, filename, use_compression, filesuffix)
_open = gzip.open if use_comp else open
fp = self.get_filepath(filename, filesuffix=filesuffix)
-> 3178 with _open(fp, 'rb') as f:
   try:
       out = pickle.load(f)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/gzip.py:58, in open(filename, mode, compresslevel, encoding, errors, newline)
gz_mode = mode.replace("t", "")
if isinstance(filename, (str, bytes, os.PathLike)):
---> 58     binary_file = GzipFile(filename, gz_mode, compresslevel)
elif hasattr(filename, "read") or hasattr(filename, "write"):
   binary_file = GzipFile(None, gz_mode, compresslevel, filename)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/gzip.py:174, in GzipFile.__init__(self, filename, mode, compresslevel, fileobj, mtime)
   mode += 'b'
if fileobj is None:
--> 174     fileobj = self.myfileobj = builtins.open(filename, mode or 'rb')
if filename is None:
   filename = getattr(fileobj, 'name', '')

FileNotFoundError: [Errno 2] No such file or directory: '/tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/inversion_flowlines.pkl'

Guidance on utilizing various baseline climates:

Currently, OGGM supports a variety of baseline climates, including ‘CRU’, ‘HISTALP’, ‘W5E5’, ‘GSWP3_W5E5’ (the default), ‘ERA5’, ‘ERA5L’, ‘CERA’, ‘ERA5dr’, and ‘ERA5L-HMA’. Although switching between these datasets is straightforward, calibrating the mass balance model according to each dataset is more complex. For instance, you’ll need to choose a default precipitation factor that suits both your selected climate dataset and your specific region. Additionally, you must determine the best method to calibrate the mass balance parameters. For a comprehensive guide on the available options, explanations, and how to incorporate your own geodetic observations, please refer to the tutorial massbalance_calibration.

Here’s an example of using the ERA5 dataset:

# define the baseline climate and add it
cfg.PARAMS['baseline_climate'] = 'ERA5'
workflow.execute_entity_task(tasks.process_climate_data, gdirs);

# define the default precipitation factor
cfg.PARAMS['prcp_fac'] = 1.6  # Note: This is not a universial value!
cfg.PARAMS['use_winter_prcp_fac'] = False  # This option is only available for 'GSWP3_W5E5'
cfg.PARAMS['use_temp_bias_from_file'] = False  # This option is only available for 'GSWP3_W5E5'

# an example of static calibration for mass balance, more options are available in the tutorial
workflow.execute_entity_task(tasks.mb_calibration_from_geodetic_mb,
                             gdirs,
                             calibrate_param1='melt_f',
                             calibrate_param2='prcp_fac',
                             calibrate_param3='temp_bias')

You can also utilize your own climate data. However, you will need to either convert your data into a specific format (for an example, see OGGM/oggm-sample-data ->test-files/histalp_merged_hef.nc) or create your own tasks.process_climate_data function. Here’s how you might do this:

cfg.PARAMS['baseline_climate'] = 'CUSTOM'
cfg.PATHS['climate_file'] = path_to_the_climate_file

workflow.execute_entity_task(tasks.process_climate_data, gdirs);

# proceed with defining the default precipitation factor and mass balance calibration as shown above

# Instruction for beginning with existing OGGM's preprocessed directories
if load_from_prepro_base_url:
    # to start from level 3 you can do
    if flowline_type_to_use == 'elevation_band':
        prepro_base_url_L3 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L3-L5_files/2023.3/elev_bands/W5E5/'
    elif flowline_type_to_use == 'centerline':
        prepro_base_url_L3 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L3-L5_files/2023.3/centerlines/W5E5/'
    else:
        raise ValueError(f"Unknown flowline type '{flowline_type_to_use}'! Select 'elevation_band' or 'centerline'!")

    gdirs = workflow.init_glacier_directories(rgi_ids,
                                              from_prepro_level=3,
                                              prepro_base_url=prepro_base_url_L3,
                                              prepro_border=80,  # could be 80 or 160
                                              reset=True,
                                              force=True,
                                             )

Level 4#

Tasks:

Initialize the current state of the glacier without a dynamic spinup. This method, default until version 1.6., is mainly for comparison purposes and can often be skipped.
Initialize the current glacier state with a dynamic spinup. This process includes a dynamic calibration of the mass balance. It’s important to note that this option isn’t available for centerlines in the current OGGM preprocessed directories, meaning it hasn’t been tested or analyzed.

Data used:

Geodetic mass balance observations (default source: Hugonnet al. 2021)

Related Tutorials:

10 minutes to… the new dynamical spinup in OGGM v1.6
dynamical_spinup: a deeper dive into the dynamical spinup for past simulations
numeric_solvers: Understand the difference between the ice dynamic solvers in OGGM

# set the ice dynamic solver depending on the flowline-type
if flowline_type_to_use == 'elevation_band':
    cfg.PARAMS['evolution_model'] = 'SemiImplicit'
elif flowline_type_to_use == 'centerline':
    cfg.PARAMS['evolution_model'] = 'FluxBased'
else:
    raise ValueError(f"Unknown flowline type '{flowline_type_to_use}'! Select 'elevation_band' or 'centerline'!")

# get the start and end year of the selected baseline
y0 = gdirs[0].get_climate_info()['baseline_yr_0']
ye = gdirs[0].get_climate_info()['baseline_yr_1'] + 1  # run really to the end until 1.1.

# 'static' initialisation
workflow.execute_entity_task(tasks.run_from_climate_data, gdirs,
                             min_ys=y0, ye=ye,
                             fixed_geometry_spinup_yr=None,  # here you could add a static spinup if you want
                             output_filesuffix='_historical')

# 'dynamic' initialisation, including dynamic mb calibration
dynamic_spinup_start_year = 1979
minimise_for = 'area'  # other option would be 'volume'
workflow.execute_entity_task(
    tasks.run_dynamic_melt_f_calibration, gdirs,
    err_dmdtda_scaling_factor=0.2,  # by default we reduce the mass balance error for accounting for
    # corrleated uncertainties on a regional scale
    ys=dynamic_spinup_start_year, ye=ye,
    kwargs_run_function={'minimise_for': minimise_for},
    ignore_errors=True,
    kwargs_fallback_function={'minimise_for': minimise_for},
    output_filesuffix='_spinup_historical',
);

2024-04-25 13:51:42: oggm.workflow: Execute entity tasks [run_from_climate_data] on 1 glaciers
2024-04-25 13:51:42: oggm.core.flowline: InvalidWorkflowError occurred during task run_from_climate_data_historical on RGI60-11.00897: Need a valid `model_flowlines` file. If you explicitly want to use `inversion_flowlines`, set use_inversion_flowlines=True.

---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/massbalance.py:1188, in MultipleFlowlineMassBalance.__init__(self, gdir, fls, mb_model_class, use_inversion_flowlines, input_filesuffix, **kwargs)
   1187 try:
-> 1188     fls = gdir.read_pickle('model_flowlines')
   1189 except FileNotFoundError:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:3178, in GlacierDirectory.read_pickle(self, filename, use_compression, filesuffix)
   3177 fp = self.get_filepath(filename, filesuffix=filesuffix)
-> 3178 with _open(fp, 'rb') as f:
   3179     try:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/gzip.py:58, in open(filename, mode, compresslevel, encoding, errors, newline)
     57 if isinstance(filename, (str, bytes, os.PathLike)):
---> 58     binary_file = GzipFile(filename, gz_mode, compresslevel)
     59 elif hasattr(filename, "read") or hasattr(filename, "write"):

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/gzip.py:174, in GzipFile.__init__(self, filename, mode, compresslevel, fileobj, mtime)
    173 if fileobj is None:
--> 174     fileobj = self.myfileobj = builtins.open(filename, mode or 'rb')
    175 if filename is None:

FileNotFoundError: [Errno 2] No such file or directory: '/tmp/OGGM/OGGM-full_prepro_elevation_bands/per_glacier/RGI60-11/RGI60-11.00/RGI60-11.00897/model_flowlines.pkl'

During handling of the above exception, another exception occurred:

InvalidWorkflowError                      Traceback (most recent call last)
Cell In[14], line 14
     11 ye = gdirs[0].get_climate_info()['baseline_yr_1'] + 1  # run really to the end until 1.1.
     13 # 'static' initialisation
---> 14 workflow.execute_entity_task(tasks.run_from_climate_data, gdirs,
     15                              min_ys=y0, ye=ye,
     16                              fixed_geometry_spinup_yr=None,  # here you could add a static spinup if you want
     17                              output_filesuffix='_historical')
     19 # 'dynamic' initialisation, including dynamic mb calibration
     20 dynamic_spinup_start_year = 1979

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in execute_entity_task(task, gdirs, **kwargs)
    188     if ng > 3:
    189         log.workflow('WARNING: you are trying to run an entity task on '
    190                      '%d glaciers with multiprocessing turned off. OGGM '
    191                      'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
    194 return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:192, in <listcomp>(.0)
    188     if ng > 3:
    189         log.workflow('WARNING: you are trying to run an entity task on '
    190                      '%d glaciers with multiprocessing turned off. OGGM '
    191                      'will run faster with multiprocessing turned on.', ng)
--> 192     out = [pc(gdir) for gdir in gdirs]
    194 return out

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:109, in _pickle_copier.__call__(self, arg)
    107 for func in self.call_func:
    108     func, kwargs = func
--> 109     res = self._call_internal(func, arg, kwargs)
    110 return res

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/workflow.py:103, in _pickle_copier._call_internal(self, call_func, gdir, kwargs)
    100     gdir, gdir_kwargs = gdir
    101     kwargs.update(gdir_kwargs)
--> 103 return call_func(gdir, **kwargs)

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/utils/_workflow.py:492, in entity_task.__call__.<locals>._entity_task(gdir, reset, print_log, return_value, continue_on_error, add_to_log_file, **kwargs)
    490     signal.alarm(cfg.PARAMS['task_timeout'])
    491 ex_t = time.time()
--> 492 out = task_func(gdir, **kwargs)
    493 ex_t = time.time() - ex_t
    494 if cfg.PARAMS['task_timeout'] > 0:

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/flowline.py:3730, in run_from_climate_data(gdir, ys, ye, min_ys, max_ys, fixed_geometry_spinup_yr, store_monthly_step, store_model_geometry, store_fl_diagnostics, climate_filename, mb_model, mb_model_class, climate_input_filesuffix, output_filesuffix, init_model_filesuffix, init_model_yr, init_model_fls, zero_initial_glacier, bias, temperature_bias, precipitation_factor, **kwargs)
   3727     ys = ys if ys < max_ys else max_ys
   3729 if mb_model is None:
-> 3730     mb_model = MultipleFlowlineMassBalance(gdir,
   3731                                            mb_model_class=mb_model_class,
   3732                                            filename=climate_filename,
   3733                                            bias=bias,
   3734                                            input_filesuffix=climate_input_filesuffix)
   3736 if temperature_bias is not None:
   3737     mb_model.temp_bias += temperature_bias

File /usr/local/pyenv/versions/3.11.9/lib/python3.11/site-packages/oggm/core/massbalance.py:1190, in MultipleFlowlineMassBalance.__init__(self, gdir, fls, mb_model_class, use_inversion_flowlines, input_filesuffix, **kwargs)
   1188         fls = gdir.read_pickle('model_flowlines')
   1189     except FileNotFoundError:
-> 1190         raise InvalidWorkflowError('Need a valid `model_flowlines` '
   1191                                    'file. If you explicitly want to '
   1192                                    'use `inversion_flowlines`, set '
   1193                                    'use_inversion_flowlines=True.')
   1195 self.fls = fls
   1197 # Initialise the mb models

InvalidWorkflowError: Need a valid `model_flowlines` file. If you explicitly want to use `inversion_flowlines`, set use_inversion_flowlines=True.

# Instruction for beginning with existing OGGM's preprocessed directories
if load_from_prepro_base_url:
    # to start from level 4 you can do
    if flowline_type_to_use == 'elevation_band':
        prepro_base_url_L4 = DEFAULT_BASE_URL
    elif flowline_type_to_use == 'centerline':
        prepro_base_url_L4 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L3-L5_files/2023.3/centerlines/W5E5/'
    else:
        raise ValueError(f"Unknown flowline type '{flowline_type_to_use}'! Select 'elevation_band' or 'centerline'!")
    gdirs = workflow.init_glacier_directories(rgi_ids,
                                              from_prepro_level=4,
                                              prepro_base_url=prepro_base_url_L4,
                                              prepro_border=80,  # could be 80 or 160
                                              reset=True,
                                              force=True,
                                             )

Level 5#

Tasks:

Retain only the data necessary for future projection runs to conserve disk space. At this stage, it’s not possible to revisit the preprocessing steps from earlier levels, but all required information for conducting future projection runs is preserved.

Data used:

No additional data is needed for this level.

Related Tutorials:

store_and_compress_glacierdirs: storing glacier directories for later use

mini_base_dir = os.path.join(cfg.PATHS['working_dir'],
                             'mini_per_glacier')
mini_gdirs = workflow.execute_entity_task(tasks.copy_to_basedir, gdirs,
                                          base_dir=mini_base_dir,
                                          setup='run/spinup')

2024-04-25 13:51:43: oggm.workflow: Execute entity tasks [copy_to_basedir] on 1 glaciers

When you're ready to access your work later, you should first remove the 'per_glacier' folder from your working directory. Then, rename the 'mini_per_glacier' folder to 'per_glacier'. Remember, proceed with these steps only if you've completed setting up your glacier directories (gdirs) and are sure you won't need to make further changes!

# Instruction for beginning with existing OGGM's preprocessed directories
if load_from_prepro_base_url:
    # to start from level 5 you can do
    if flowline_type_to_use == 'elevation_band':
        prepro_base_url_L5 = DEFAULT_BASE_URL
    elif flowline_type_to_use == 'centerline':
        prepro_base_url_L5 = 'https://cluster.klima.uni-bremen.de/~oggm/gdirs/oggm_v1.6/L3-L5_files/2023.3/centerlines/W5E5/'
    else:
        raise ValueError(f"Unknown flowline type '{flowline_type_to_use}'! Select 'elevation_band' or 'centerline'!")
    gdirs = workflow.init_glacier_directories(rgi_ids,
                                              from_prepro_level=5,
                                              prepro_base_url=prepro_base_url_L5,
                                              prepro_border=80,  # could be 80 or 160
                                              reset=True,
                                              force=True,
                                             )

And that’s it! We’ve successfully recreated all the preprocessed levels offered by OGGM. Remember, if you prefer, you can bypass all previous steps and jump straight into your future projections from Level 5. Happy modeling!

What’s next?#

return to the OGGM documentation
back to the table of contents

Step-by-Step guide to rebuilding the preprocessed directories from scratch

Contents

Step-by-Step guide to rebuilding the preprocessed directories from scratch#

Set-up#

Level 0#

Level 1#

Level 2#

Level 3#

Level 4#

Level 5#

What’s next?#