Dealing with errors after a run#

In this example, we run the model on a list of three glaciers: two of them will end with errors: one because it already failed at preprocessing (i.e. prior to this run), and one during the run. We show how to analyze theses erros and solve (some) of them, as described in the OGGM documentation under troubleshooting.

Run with cfg.PARAMS['continue_on_error'] = True#

# Locals
import oggm.cfg as cfg
from oggm import utils, workflow, tasks

# Libs
import os
import xarray as xr
import pandas as pd

# Initialize OGGM and set up the default run parameters

# Here we override some of the default parameters
# How many grid points around the glacier?
# We make it small because we want the model to error because
# of flowing out of the domain
cfg.PARAMS['border'] = 80

# This is useful since we have three glaciers
cfg.PARAMS['use_multiprocessing'] = True

# This is the important bit!
# We tell OGGM to continue despite of errors
cfg.PARAMS['continue_on_error'] = True

# Local working directory (where OGGM will write its output)
WORKING_DIR = utils.gettempdir('OGGM_Errors', reset=True)
cfg.PATHS['working_dir'] = WORKING_DIR

rgi_ids = ['RGI60-11.00897', 'RGI60-11.01450', 'RGI60-11.03295']

# Go - get the pre-processed glacier directories
gdirs = workflow.init_glacier_directories(rgi_ids, from_prepro_level=4)

# We can step directly to the experiment!
# Random climate representative for the recent climate (1985-2015)
# with a negative bias added to the random temperature series
workflow.execute_entity_task(tasks.run_random_climate, gdirs,
                             nyears=150, seed=0,
2023-03-07 12:24:43: oggm.cfg: Reading default parameters from the OGGM `params.cfg` configuration file.
2023-03-07 12:24:43: oggm.cfg: Multiprocessing switched OFF according to the parameter file.
2023-03-07 12:24:43: oggm.cfg: Multiprocessing: using all available processors (N=2)
2023-03-07 12:24:43: oggm.cfg: PARAMS['border'] changed from `40` to `80`.
2023-03-07 12:24:43: oggm.cfg: Multiprocessing switched ON after user settings.
2023-03-07 12:24:43: oggm.cfg: PARAMS['continue_on_error'] changed from `False` to `True`.
2023-03-07 12:24:43: oggm.workflow: init_glacier_directories from prepro level 4 on 3 glaciers.
2023-03-07 12:24:43: oggm.workflow: Execute entity tasks [gdir_from_prepro] on 3 glaciers
RemoteTraceback                           Traceback (most recent call last)
Traceback (most recent call last):
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/multiprocessing/", line 125, in worker
    result = (True, func(*args, **kwds))
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/multiprocessing/", line 48, in mapstar
    return list(map(*args))
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/", line 108, in __call__
    res = self._call_internal(func, arg, kwargs)
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/", line 102, in _call_internal
    return call_func(gdir, **kwargs)
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/", line 251, in gdir_from_prepro
    return oggm.GlacierDirectory(entity, from_tar=from_tar)
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/utils/", line 2529, in __init__ = filter_rgi_name(name)
  File "/usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/utils/", line 734, in filter_rgi_name
    if name is None or len(name) == 0:
TypeError: object of type 'numpy.float64' has no len()

The above exception was the direct cause of the following exception:

TypeError                                 Traceback (most recent call last)
Cell In[1], line 33
     30 rgi_ids = ['RGI60-11.00897', 'RGI60-11.01450', 'RGI60-11.03295']
     32 # Go - get the pre-processed glacier directories
---> 33 gdirs = workflow.init_glacier_directories(rgi_ids, from_prepro_level=4)
     35 # We can step directly to the experiment!
     36 # Random climate representative for the recent climate (1985-2015)
     37 # with a negative bias added to the random temperature series
     38 workflow.execute_entity_task(tasks.run_random_climate, gdirs,
     39                              nyears=150, seed=0,
     40                              temperature_bias=-1)

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/, in init_glacier_directories(rgidf, reset, force, from_prepro_level, prepro_border, prepro_rgi_version, prepro_base_url, from_tar, delete_tar)
    531     if cfg.PARAMS['dl_verify']:
    532         utils.get_dl_verify_data('')
--> 533     gdirs = execute_entity_task(gdir_from_prepro, entities,
    534                                 from_prepro_level=from_prepro_level,
    535                                 prepro_border=prepro_border,
    536                                 prepro_rgi_version=prepro_rgi_version,
    537                                 base_url=prepro_base_url)
    538 else:
    539     # We can set the intersects file automatically here
    540     if (cfg.PARAMS['use_intersects'] and
    541             len(cfg.PARAMS['intersects_gdf']) == 0 and
    542             not from_tar):

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/, in execute_entity_task(task, gdirs, **kwargs)
    183 if cfg.PARAMS['use_multiprocessing'] and ng > 1:
    184     mppool = init_mp_pool(cfg.CONFIG_MODIFIED)
--> 185     out =, gdirs, chunksize=1)
    186 else:
    187     if ng > 3:

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/multiprocessing/, in, func, iterable, chunksize)
    362 def map(self, func, iterable, chunksize=None):
    363     '''
    364     Apply `func` to each element in `iterable`, collecting the results
    365     in a list that is returned.
    366     '''
--> 367     return self._map_async(func, iterable, mapstar, chunksize).get()

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/multiprocessing/, in ApplyResult.get(self, timeout)
    772     return self._value
    773 else:
--> 774     raise self._value

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/multiprocessing/, in worker()
    123 job, i, func, args, kwds = task
    124 try:
--> 125     result = (True, func(*args, **kwds))
    126 except Exception as e:
    127     if wrap_exception and func is not _helper_reraises_exception:

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/multiprocessing/, in mapstar()
     47 def mapstar(args):
---> 48     return list(map(*args))

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/, in __call__()
    106 for func in self.call_func:
    107     func, kwargs = func
--> 108     res = self._call_internal(func, arg, kwargs)
    109 return res

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/, in _call_internal()
     99     gdir, gdir_kwargs = gdir
    100     kwargs.update(gdir_kwargs)
--> 102 return call_func(gdir, **kwargs)

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/, in gdir_from_prepro()
    248 tar_base = utils.get_prepro_gdir(prepro_rgi_version, rid, prepro_border,
    249                                  from_prepro_level, base_url=base_url)
    250 from_tar = os.path.join(tar_base.replace('.tar', ''), rid + '.tar.gz')
--> 251 return oggm.GlacierDirectory(entity, from_tar=from_tar)

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/utils/, in __init__()
   2525     raise RuntimeError('RGI Version not supported: '
   2526                        '{}'.format(self.rgi_version))
   2528 # remove spurious characters and trailing blanks
-> 2529 = filter_rgi_name(name)
   2531 # region
   2532 reg_names, subreg_names = parse_rgi_meta(version=self.rgi_version[0])

File /usr/local/pyenv/versions/3.10.10/lib/python3.10/site-packages/oggm/utils/, in filter_rgi_name()
    728 def filter_rgi_name(name):
    729     """Remove spurious characters and trailing blanks from RGI glacier name.
    731     This seems to be unnecessary with RGI V6
    732     """
--> 734     if name is None or len(name) == 0:
    735         return ''
    737     if name[-1] in ['À', 'È', 'è', '\x9c', '3', 'Ð', '°', '¾',
    738                     '\r', '\x93', '¤', '0', '`', '/', 'C', '@',
    739                     'Å', '\x06', '\x10', '^', 'å', ';']:

TypeError: object of type 'numpy.float64' has no len()

Error diagnostics#

# Write the compiled output
utils.compile_glacier_statistics(gdirs);  # saved as glacier_statistics.csv in the WORKING_DIR folder
utils.compile_run_output(gdirs);  # saved as in the WORKING_DIR folder
# Read it
with xr.open_dataset(os.path.join(WORKING_DIR, '')) as ds:
    ds = ds.load()
df_stats = pd.read_csv(os.path.join(WORKING_DIR, 'glacier_statistics.csv'), index_col=0)
# all possible statistics about the glaciers
  • in the column error_task, we can see whether an error occurred, and if yes during which task

  • error_msg describes the actual error message

df_stats[['error_task', 'error_msg']]

We can also check which glacier failed at which task by using compile_task_log.

# also saved as task_log.csv in the WORKING_DIR folder - "append=False" replaces the existing one
utils.compile_task_log(gdirs, task_names=['glacier_masks', 'compute_centerlines', 'flowline_model_run'], append=False)

Error solving#

RuntimeError: Glacier exceeds domain boundaries, at year: 98.08333333333333#

To remove this error just increase the domain boundary before running init_glacier_directories ! Attention, this means that more data has to be downloaded and the run takes more time. The available options for cfg.PARAMS['border'] are 10, 40, 80 or 160 at the moment; the unit is number of grid points outside the glacier boundaries. More about that in the OGGM documentation under preprocessed files.

# reset to recompute statistics
# Beware! If you use `reset=True` in `utils.mkdir`, ALL DATA in this folder will be deleted!
utils.mkdir(WORKING_DIR, reset=True)

# increase the amount of gridpoints outside the glacier
cfg.PARAMS['border'] = 160
gdirs = workflow.init_glacier_directories(rgi_ids, from_prepro_level=4)
workflow.execute_entity_task(tasks.run_random_climate, gdirs,
                             nyears=150, seed=0,

# recompute the output
# we can also get the run output directly from the methods
df_stats = utils.compile_glacier_statistics(gdirs)
ds = utils.compile_run_output(gdirs)
# check again
df_stats[['error_task', 'error_msg']]

Now RGI60-11.00897 runs without errors!

Error: Need a valid model_flowlines file.#

This error message in the log is misleading: it does not really describe the source of the error, which happened earlier in the processing chain. Therefore we can look instead into the glacier_statistics via compile_glacier_statistics or into the log output via compile_task_log:

print('error_task: {}, error_msg: {}'.format(df_stats.loc['RGI60-11.03295']['error_task'],

Now we have a better understanding of the error:

  • OGGM can not work with this geometry of this glacier and could therefore not make a gridded mask of the glacier outlines.

  • there is no way to prevent this except you find a better way to pre-process the geometry of this glacier

  • these glaciers have to be ignored! Less than 0.5% of glacier area globally have errors during the geometry processing or failures in computing certain topographical properties by e.g. invalid DEM, see Sect. 4.2 Invalid Glaciers of the OGGM paper (Maussion et al., 2019) and this tutorial for more up-to-date numbers

Ignoring those glaciers with errors that we can’t solve#

In the run_output, you can for example just use *.dropna to remove these. For other applications (e.g. quantitative mass change evaluation), more will be needed (not available yet in the OGGM codebase):

ds.dropna(dim='rgi_id')  # here we can e.g. find the volume evolution

What’s next?#