# Version history#

## v1.6.0 (unreleased)#

A new major release of the OGGM with several important changes. We recommend all users to switch to this version only if they are ready for a new study, or rerun their simulations.

### Breaking changes#

• we removed the init_glacier_regions task, which was deprecated since a few OGGM versions. Similarly, other old functions (e.g. process_cmip5_data) were also removed.

• several default parameters were updated to new values. See “migrating guide” below to navigate through these changes.

• the calibration of the mass balance models with the $$t^*$$ (“T star”) method is no longer supported. The code is here and can be used, but we don’t use it ourselves anymore.

### Enhancements#

• added support for new reference data (W5E5), a bias corrected dataset based on ERA5. This will become the new default in OGGM (PR1435). By Lilian Schuster

• added support for a precipitation factor varying per glacier (PR1435). By Lilian Schuster

• Added a new entity task run_dynamic_mu_star_calibration. This task dynamically calibrates the temperature sensitivity mu star to a geodetic mass-balance observation. There are different options available how this is done, the default incorporates an inversion and a dynamic spinup in each iteration (PR1425). By Patrick Schmitt

• Added two new output variables in FlowlineModel.run_until_and_store() (area_m2_min_h and volume_m3_min_h) which are needed for a dynamic mu star calibration which should include the minimum ice thickness argument of an dynamic spinup (needed as a filter for interannual changes of especially the area). Also included cfg.PARAMS['dynamic_spinup_min_ice_thick'] to be able to globally define the used minimum ice thickness for the dynamic spinup (PR1425). By Patrick Schmitt

• Rearanged the entity tasks run_dynamic_mu_star_calibration and run_dynamic_spinup with all help functions in new modul oggm.core.dynamic_spinup (PR1425). By Patrick Schmitt

• Rearanged the prepro levels. Level 4 now adds a historical run (previously done in level 5) and a spinup historical run (using dynamic mu star calibration). Level 5 now replaces level 4 and creates the minigdirs (where only the files for a model run are kept and no inversion is possible anymore) (PR1425). By Patrick Schmitt

• Added support for Millan et al 2022 velocity and thickness in the shop (PR1443). By Fabien Maussion

• Added trapezoidal downstream line (PR1491). Can be selected with cfg.PARAMS['downstream_line_shape'], with the options 'parabol' (default) or 'trapezoidal' before calling init_present_time_glacier(gdir). By Patrick Schmitt

• Added option to plot flowline velocities in graphics.plot_modeloutput_map() (PR1496). By Patrick Schmitt

• Added option to extend the plot limits when plotting multiple gdirs. Could be used with extend_plot_limits=True, e.g. graphics.plot_modeloutput_map(gdirs, extend_plot_limits=True) (PR1508). By Patrick Schmitt

• Added new argument add_fixed_geometry_spinup to extend the model run of run_dynamic_spinup with a fixed-geometry-spinup if the spinup period is shortened(PR1514) By Patrick Schmitt

• Added SemiImplicitModel for a single trapezoid or rectangular flowline developed by Dan Goldberg (PR1507) By Patrick Schmitt

• Added the possibility to use the UTM map proj instead of the local TM used by OGGM usually (PR1526). Leads to qualitative and quantitative differences when used. By Fabien Maussion

### Bug fixes#

• corrected a but in apparent_mb_from_any_mb, where only two years of MB would be used instead of a range of years (PR1426). By Bowen

• Corrected source argument in tasks.define_glacier_region to handle a list of DEM sources. (PR1506). By Daniel Otto

Some text here.

## v1.5.3 (02.04.2022)#

New release of the OGGM model, setting the ground for a major update to be released soon. Several major improvements available for testing, and will become the default in a future major release:

• new MassRedistributionCurveModel which uses the Huss curves to parameterize glacier retreat.

• new mu_star_calibration_from_geodetic_mb task which now calibrates each glacier individually

• new run_dynamic_spinup task which used the ice dynamics model to spinup the model (instead of the default equilibrium assumption)

• and much more! See below.

### Breaking changes#

• In the process of adding new output diagnostic files (PR1308), the signature and return output of FlowlineModel.run_until_and_store changed. We hope that this change won’t affect too many of our users but if it does, it should be relatively straightforward to update your code: users now control the number of outputs with the fl_diag_path and geom_path kwargs. Most users will probably have used the run_* tasks anyway, and won’t be affected by this change (except maybe for the point below). By Fabien Maussion

• Furthermore, cfg.PARAMS['store_model_geometry'] is now set to False per default. If you were relying on these files (e.g. for a run with spinup or similar), your code will fail with FileNotFoundError for the model_geometry files. Setting cfg.PARAMS['store_model_geometry'] back to True should solve the issue.

• Copernicus DEM 90m is now called 'COPDEM90' instead of 'COPDEM' and also uses the 2021 release with additional data corrections (PR1364).

### Enhancements & bug fixes#

• Added the ELA back as a variable. Unlike before it is now a diagnostic variable that can be computed independent of a model run with global_tasks.compile_ela (PR1333). By Anouk Vlug

• Added a prescribe_years kwarg to RandomMassBalance to control which years are picked instead of the random number generator (PR1310). By Fabien Maussion

• Added a stop_criterion kwarg to run_until_and_store, so that users can specify when a simulation has to stop based on their chosen criteria (PR1303). By Fabien Maussion

• Implemented a MassRedistributionCurveModel under the FlowlineModel interface, which uses the Huss curves to parameterize glacier retreat. There is some parameterisation for advance as well, but a very coarse one (PR1288). By Fabien Maussion

• Added a new mu_star_calibration_from_geodetic_mb task which now calibrates each glacier individually from the reference geodetic MB data. This is a rather quick solution for now, but it opens new avenues (PR1286). A bug in the new feature was later corrected (PR1351). By Fabien Maussion and Lilian Schuster

• Added a new utils.get_geodetic_mb_dataframe which returns the reference geodetic MB data, currently from Hugonnet et al 2021. Also changed the behavior of cfg.DATA to be shared across processes (PR1285). By Fabien Maussion

• Added a new output diagnostic files containing variables along the flowlines instead of aggregated at the glacier level (PR1308). These files are stored in the glacier directory (gdir.get_filepath('fl_diagnostics')) and are not saved per default. Set cfg.PARAMS['store_fl_diagnostics'] = True to activate it. By Fabien Maussion

• Added a new keyword argument to run_with_hydro, run_from_climate_data, and run_until_and_store: fixed_geometry_spinup_yr which allows to “start” a simulation at an earlier date than the RGI date (PR1327). In practice, it computes the glacier volume change from SMB only (fixed geometry), ignoring glacier area change in this period. Therefore, it is only valid for short periods of times (years, not decades). By Fabien Maussion

• Added new keyword arguments to run_with_hydro which allow to select which glacier area should be used as reference for the hydro computations (PR1331). Furthermore, it also allows to use a previous geometry file for the computations, i.e. allowing for continuous historical to projections outputs (if needed). By Fabien Maussion

• The package “descartes” is no longer a required dependency for oggm.

• Added a new entity task run_dynamic_spinup. This task dynamically spinup the glacier to match the area or volume at the RGI date. To do so the glacier is simulated from the recent past (default 1980) to the RGI date. The unknown glacier geometry at the start of the simulation is iteratively changed with a short constant climate run with a varying temperature bias (PR1342, PR1361). By Patrick Schmitt

• Added new options to write_centerlines_to_shape which allow to output smoother and more correct centerlines (PR1357). By Fabien Maussion

• Added the 30m version of the Copernicus DEM. This DEM can be set with source='COPDEM30' and can be useful for smaller sized glaciers. An account with Copernicus is required to access the DEM (free for academics). (PR1364). By Matthias Dusch

• Added a new merge_consecutive_run_outputs entity task which allows to merge two output files together (PR1379). This is useful to merge e.g. spinup + historical or historical + projection runs in post-processing. By Fabien Maussion

## v1.5.2 (29.08.2021)#

Very minor release to remove the dependency on the python-colorspace package.

### Breaking changes#

• Removed use and dependency on the python-colorspace package. Although not very dramatic, this change might change the way your plots look like (PR1284). Users can specify their own colormaps anyways to get back to the old plots. By Fabien Maussion

## v1.5.1 (28.08.2021)#

This is a minor release of OGGM, containing mostly bugfixes and a few new features.

### Breaking changes#

This version should be fully backwards compatible.

### Enhancements#

• Added cook_rgidf() function in oggm.utils to simplify the use of a non-RGI glacier inventory in OGGM (PR1251). By Li Fei

• Added support for last millennium reanalysis data to the shop (PR1257). By Fabien Maussion

• Added a new apply_func argument in utils.compile_glacier_statistics that allows user to compute any new statistics from a gdir themselves (PR1259) By Li Fei

• Added a new workflow.match_geodetic_mb_for_selection function to match the MB bias for any selection of glaciers (PR1248) By Patrick Schmitt

• Added functionality to control the area over which the hydrological output is computed (PR1264, PR1276). By Fabien Maussion

• Added a new (wrong) way to compute equilibrium runs based on the average climate (PR1275). By Fabien Maussion

### Bug fixes#

• Fixed a quite bad bug where monthly runoff data would have very large artifacts (PR1283). By Fabien Maussion

• Small bug fix to ensure backwards compatibility of gdir.get_filepath('model_run'). By Fabien Maussion

• Various backwards compatibility fixes (mostly xarray).

## v1.5.0#

This a new update of the OGGM model. It should be largely compatible with OGGM v1.4.0. The main addition in this release is the computation of hydrological diagnostics. Check-out the new tutorial at https://oggm.org/tutorials !

### Breaking changes#

• Mass balance models now do their computations with float64 arrays instead of float32 (PR1211). By Lilian Schuster

• prcp_bias renamed to prcp_fac in mass balance models (PR1211). By Lilian Schuster

• Various name changes (with deprecation cycle, i.e. old code should still work): gdir.get_filepath('model_run') renamed to gdir.get_filepath('model_geometry'); run_path kwarg in run_until_and_store renamed to geom_path.

### Enhancements#

• Mass balance models now properly refer to prcp_fac (was incorrectly named prcp_bias) (PR1211). Additionally, the run_* tasks in oggm.core.flowline can now also adjust the precipitation factor for sensitivity experiments. By Lilian Schuster

• Users can now choose the variables that are written in diagnostics files and can also choose not to write the glacier geometry files during the run (PR1219). The respective global parameters are store_diagnostic_variables and store_model_geometry. By Fabien Maussion

• Added experimental run_with_hydro task which computes hydrological diagnostics after a standard dynamical run (PR1224). This is highly experimental, will likely change in the future. By Fabien Maussion

• Added monthly output to run_with_hydro (PR1232). By Sarah Hanus and Fabien Maussion

• Added new diagnostic variables (terminus_thick_0 …) to better track the thickness at the terminus (PR1230). By Fabien Maussion

• Temperature and precipitation corrections can now also be applied on a monthly basis for the PastMassBalanceModel (PR1247). By Fabien Maussion

### Bug fixes#

• Fixed bug in hydro date / calendar date conversions with month=1 (i.e. no conversion) (PR1220). By Lilian Schuster

• Fixed bug in graphics.plot_distributed_thickness which led to an error with elevation bands flowlines (PR1241). By Li Fei

## v1.4.0 (17.02.2021)#

This a new major update of the OGGM model. It it the result of one year of development, with several non-backwards compatible changes.

We recommend all users to update to this version.

Major new release 1.4!

There have been a large number of additions too long to be summarized, and the list below is far from complete (we have waited way too long for this release). Here are the highlights:

• new option to compute centerlines: “elevation band flowlines”

• new option to calibrate OGGM mass balance regionally to geodetic estimates

• new option to calibrate the creep parameter Glen A to match the ice thickness to the Farinotti et al. (2019) consensus

• users can now choose from a variety of pre-processed directories, including with new climate data (e.g. ERA5)

• OGGM now has a calving parameterization (switched off per default)

• OGGM shop, to download several new input datasets

• Historical runs (“spin-up”) are now available per default and can be readily used for projections

• and much much more….

Note: not all changes since v1.3.1 are documented below. We’ll try to be better with documenting changes in the future.

### Breaking changes#

• The dynamical model now has a “real” parameterization for calving (WIP). A blog post explaining it can be found on the website (PR945). By Fabien Maussion

• The calving parameterization has been extended and made more useful by logging its output to compiled files. See PR996 for code changes and watch out for upcoming changes in the documentation and notebooks. By Fabien Maussion

• The new default when applying GCM data to a glacier is to correct for temperature standard deviation (PR978). The previous default was wrong and should not be the default. By Fabien Maussion

• Added a new “glacier directory initialization” global task: init_glacier_directories (PR983, GH965). It replaces init_glacier_regions and covers all its functionality, except that it does not process the DEM data (this was a confusing “feature” of init_glacier_regions). The old task init_glacier_regions is officially deprecated but without warnings for now. Since it is a very widely used task, we prefer to deprecate it in a slow cycle: first, change the documentation, deprecate later. By Fabien Maussion

• More climate datasets are now supported in OGGM (PR1036). A new task (historical_climate_qc) has been added to quality check the climate timeseries. This has not been tested intensively yet and is still a WIP. By Fabien Maussion

• The order of the tasks applied to the preprocessed levels has changed, climate data comes in later (PR1038). By Fabien Maussion

• The default DEMS used for each glacier have changed for more modern ones (PR1073). By Fabien Maussion

• The inversion tasks now can invert for trapezoid shapes (PR1045). This has non-trivial consequences for the model workflow. First and foremost, the decision about using a trapezoid bed (instead of parabolic when the parabola is too “flat”) is taken at the inversion step and not afterwards. The forward model and the inversion are therefore much more consistent. Furthermore, the task filter_inversion_output was simplified to take the estimated downstream bedshapes into account and now preserves glacier area, not volume. This also is a step towards more physical consistency between inverse and forward model. By Fabien Maussion

• The vascaling module has been removed from oggm core (PR1065). It is now available via a separate package (oggm-vas, maintained by Moritz Oberrauch).

• New options to compute the length of a glacier during a run: PARAMS[‘min_ice_thick_for_length’] and PARAMS[‘glacier_length_method’] (PR1069). By Matthias Dusch.

• Several further important changes to be documented later in (PR1099). By Fabien Maussion.

## v1.3.1 (16.02.2020)#

Minor release with small improvements but an important and necessary change in multiprocessing.

### Enhancements#

• After a recent change in multiprocessing, creating a pool of workers became very slow. This change was necessary because of race conditions in GDAL, but these conditions are rarely relevant to users. We now make this change in multiprocessing optional (PR937)

• various improvements and changes in the dynamical model - mass balance model API. These were necessary to allow compatibility with the PyGEM model (PR938, PR946, PR949, PR953, PR951). By Fabien Maussion and David Rounce.

• added a “flux gate” to allow for precise mass-conservation checks in numerical experiments (PR944). By Fabien Maussion.

## v1.3.0 (02.02.2020)#

The time stepping scheme of OGGM has been fixed for several flaws. This blog post explains it in detail. We expect some changes in OGGM results after this release, but they should not be noticeable in a vast majority of the cases.

We recommend all users to update to this version.

### Breaking changes#

• The adaptive time stepping scheme of OGGM has been fixed for several flaws which lead to unstable results in certain conditions. See the blog post for a full description. The API didn’t change in the process, but the OGGM results are likely to change slightly in some conditions. (GH731, GH860, PR931). By Fabien Maussion and Alex Jarosch.

### Enhancements#

• The test_models test module has been refactored to use pytest fixtures instead of unittest classes (PR934 and PR922). By Chris Merrill.

## v1.2.0 (04.01.2020)#

OGGM is released under a new license. We now use the BSD-3-Clause license.

## v1.1.3 (03.01.2020)#

Minor release of the OGGM model with several small improvements. We don’t expect major changes in the model results due to this release.

Important: this will be the last release under a GPL license. The next release (v1.2) will be done without modifications but under a BSD-3-Clause License.

### Enhancements#

• New function cfg.add_to_basenames now allows users to define their own entries in glacier directories (GH731). By Fabien Maussion.

• New function inversion.compute_velocities writes the section and surface veloicites in the inversion output (GH876). By Beatriz Recinos.

• Added ASTER v3 as optional DEM. Requires credentials to urs.earthdata.nasa.gov stored in a local .netrc file. Credentials can be added on the command line via \$ oggm_netrc_credentials (PR884). By Matthias Dusch.

• Added a global task (tasks.compile_task_time and the associated method at the GlacierDirectory level get_task_time) to time the execution of entity tasks (GH918). By Fabien Maussion.

• Improved performance of numerical core thanks to changes in our calls to np.clip (PR873 and PR903). By Fabien Maussion.

• Added a function cfg.initialize_minimal to run the flowline model without enforcing a full download of the demo files (PR921). By Fabien Maussion.

## v1.1.2 (12.09.2019)#

Minor release of the OGGM model, with several substantial improvements, most notably:

• update in the inversion procedure for calving glaciers (Recinos et al., 2019)

• new glacier evolution model based on Marzeion et al., 2012

We don’t expect major changes in the model results due to this release.

### Breaking changes#

• run_until now makes sure that the years (months) are not crossed by the adaptive time-stepping scheme (GH710). run_until and run_until_and_store should now be consistent. The change is unlikely to affect the majority of users (which used run_until_and_store), but the results or run_until can be affected (PR726). By Matthias Dusch.

• find_inversion_calving has been renamed to find_inversion_calving_loop and will probably be deprecated soon (PR794). By Fabien Maussion.

• use_rgi_area=False now also recomputes CenLon and CenLat on the fly. (GH838). By Fabien Maussion.

### Enhancements#

• Added new gridded_attributes and gridded_mb_attributes tasks to add raster glacier attributes such as slope, aspect, mass balance… to the glacier directory (PR725). This can be useful for statistical modelling of glacier thickness. By Matteo Castellani.

• Added support for a new DEM dataset: Mapzen, found on Amazon cloud (GH748, PR759). Also added some utility functions to handle DEMs, to be improved further in the near future. By Fabien Maussion.

• Added support for a new DEM dataset: REMA (PR759). By Fabien Maussion.

• Added an option to pre-process all DEMs at once (PR771). By Fabien Maussion.

• Added support for another evolution model: the volume-area-scaling based model of Marzeion et al., 2012 (PR662). This is a major enhancement to the code base as it increases the number of choices available to users and demonstrates the modularity of the model. By Moritz Oberrauch.

• Changed the way the calving flux is computed during the ice thickness inversion. This no longer relies on an iteration over mu*, but solves for h instead. The new function is likely to replace the “old” calving loop (PR794). By Fabien Maussion.

• compile_climate_input and compile_run_output are now faster for larger numbers of glaciers thanks to temporary files (PR814). By Anouk Vlug. Could be made faster with multiprocessing one day.

• OGGM can now run in “minimal mode”, i.e. without many of the hard dependencies (GH420). This is useful for teaching or idealized simulations, but won’t work in production. By Fabien Maussion.

• the flowline model gives access to new diagnostics such as ice velocity and flux along the flowline. The numerical core code changed in the process, and we will monitor performance after this change (PR853). By Fabien Maussion.

### Bug fixes#

• Preprocessed directories at the level 3 now also have the glacier flowlines ready for the run (GH736, PR771). By Fabien Maussion.

• Nominal glaciers now error early in the processing chain (GH832). By Fabien Maussion.

• Specific MB (not used operationaly) was wrongly computer for zero ice thickness rectangular or parabolic sections. This is now corrected (GH828). By Fabien Maussion.

• Fixed a bug in model output files where SH glaciers were wrongly attributed with NH calendar dates (GH824). By Fabien Maussion.

## v1.1.1 (24.04.2019)#

Minor release of the OGGM model, with several bugfixes and some improvements.

We don’t expect any change in the model results due to this release.

### Enhancements#

• Adapted graphics.plot_domain, graphics.plot_centerlines and graphics_plot_modeloutput_map to work with merged glaciers (PR726). By Matthias Dusch.

• Added (and updated) an official task to find the calving flux based on the mass-conservation inversion (inversion.find_inversion_calving). This is still in experimentation phase! (PR720). By Beatriz Recinos.

• Added a mechanism to add custom MB data to OGGM (GH724). By Fabien Maussion.

• The ALOS Global Digital Surface Model “ALOS World 3D - 30m” DEM from JAXA can now be used as alternative DEM within OGGM (PR734). By Matthias Dusch.

• Switch to setuptools-scm as a version control system (GH727). By Timo Rothenpieler.

## v1.1 (28.02.2019)#

This is a major new release of the OGGM model, with substantial improvements to version 1. We recommend to use this version from now on. It coincides with the publication of our publication in Geoscientific Model Development.

New contributors to the project:

• Matthias Dusch (PhD student, University of Innsbruck), added extensive cross-validation tools and an associated website.

• Philipp Gregor (Master student, University of Innsbruck), added options to switch on lateral bed stress in the flowline ice dynamics

• Nicolas Champollion (PostDoc, University of Bremen), added GCM data IO routines.

• Sadie Bartholomew (Software Engineer, UK Met Office), added ability to replace colormaps in graphics with HCL-based colors using python-colorspace.

### Breaking changes#

• The utils.copy_to_basedir() function is changed to being an entity task. In addition gcm_data files, when present, will from now on always be copied when using this task (GH467 & PR468). By Anouk Vlug.

• Accumulation Area Ratio (AAR) is now correctly computed (GH361). By Fabien Maussion.

• The method used to apply CRU and GCM anomalies to the climatology has changed for precipitation: we now use scaled anomalies instead of the standard anomalies (PR393). The previous method might have lead to negative values in some cases. The corresponding reference t* have also been updated (PR407). This change has some consequences on the the model results: cross-validation indicates very similar scores, but the influence on global model output has not been assessed yet. By Fabien Maussion.

• It is now possible to run a simulation with spinup in the standard workflow (PR411). For this to happen it was necessary to clean up the many *filesuffix options. The new names are more explicit but not backwards compatible. The previous filesuffix is now called output_filesuffix. The previous input_filesuffix is now called climate_input_filesuffix. The random_glacier_evolution task is now called run_random_climate for consistency with the other tasks See the PR linked above for more info. By Fabien Maussion.

• RGI version 4 isn’t supported anymore (GH142). By Fabien Maussion.

• Rework of the 2d interpolation tasks for ice thickness in the context of ITMIX2. The new interpolation are better, but not backwards compatible. Aside of me I don’t think anybody was using them (PR465). By Fabien Maussion.

• Diagnostic variables (length, area, volume, ELA) are now stored at annual steps instead of monthly steps (PR488). The old behavior can still be used with the store_monthly_step kwarg. Most users should not notice this change because the regionally compiled files were stored at yearly steps anyways. By Fabien Maussion.

• The list of reference t* dates is now generated differently: instead of the complex (and sort of useless) nearest neighbor algorithm we are now referring back to the original method of Marzeion et al. (2012). This comes together with other breaking changes, altogether likely to change the results of the mass balance model for some glaciers. For more details see the PR: PR509 By Fabien Maussion.

• The ice dynamics parameters (Glen A, N, ice density) are now “real” parameters accessible via cfg.PARAMS (PR520, GH511 and GH27). Previously, they were also accessible via a module attribute in cfg, which was more confusing than helping. Deprecated and removed a couple of other things on the go, such as the dangerous  optimize_inversion_params task (this cannot be optimized yet) and the useless volume_inversion wrapper (now called mass_conservation_inversion) By Fabien Maussion.

• The temperature sensitivity mu* is now flowline specific, instead of glacier wide. This change was necessary because it now allows low-lying tributaries to exist, despite of too high glacier wide mu*. This change had some wider reaching consequences in the code base and in the mass balance models in particular: PR539. This will also allow to merge neighboring glaciers in the future. By Fabien Maussion.

• The “human readable” mu* information is now stored in a JSON dict instead of a csv: PR568. By Fabien Maussion.

• The global task glacier_characteristics has been renamed to compile_glacier_statistics (PR571). By Fabien Maussion.

• The process_cesm_data task has been been moved to gcm_climate.py addressing: GH469 & PR582. By Anouk Vlug.

• The shapefiles are now stored in the glacier directories as compressed tar files, addressing GH367 & GH615. This option can be turned off with cfg.PARAMS[‘use_tar_shapefiles’] = False. By Fabien Maussion.

### Enhancements#

• Added a utility function to easily get intersects files (PR402). By Fabien Maussion.

• The old GlaThiDa file linking the total volume of glaciers (T database) to RGI has been updated to RGI Version 6 (PR403). Generally, we do not recommend to use these data for calibration or validation because of largely unknown uncertainties. By Fabien Maussion.

• The computing efficiency of the 2D shallow ice model has been increased by a factor 2 (PR415), by avoiding useless repetitions of indexing operations. The results shouldn’t change at all. By Fabien Maussion.

• Added optional shape factors for mass-conservation inversion and FluxBasedModel to account for lateral drag dependent on the bed shape (PR429). Accepted settings for shape factors are None, ‘Adhikari’ (Adhikari & Marshall 2012), ‘Nye’ (Nye, 1965; equivalent to Adhikari) and ‘Huss’ (Huss & Farinotti 2012). Thorough tests with applied shape factors are still missing. By Philipp Gregor.

• Some amelioration to the mass balance models (PR434). Added a repeat kwarg to the PastMassBalance in order to loop over a selected period. Added an UncertainMassBalance model which wraps an existing model and adds random uncertainty to it. By Fabien Maussion.

• The DEM sources are now clearly stated in each glacier directory, along with the original data citation (PR441). We encourage to always cite the original data providers. By Fabien Maussion.

• Added some diagnostic tools which make it easier to detect dubious glacier outlines or DEM errors (PR445). This will be used to report to the RGI authors. By Fabien Maussion.

• Added a new parameter (PARAMS['use_rgi_area']), which specifies whether OGGM should use the reference area provided by RGI or the one computed from the local map and reprojected outlines (PR458, default: True). By Matthias Dusch.

• A new simple_glacier_masks tasks allows to compute glacier rasters in a more robust way than the default OGGM method (PR476). This is useful for simpler workflows or to compute global statistics for external tools like rgitools. This task also computes hypsometry files much like RGI does. By Fabien Maussion.

• Reference glaciers now have mass balance profiles attached to them, if available. You can get the profiles with gdir.get_ref_mb_profile() (PR493). By Fabien Maussion.

• New process_histalp_data task to run OGGM with HISTALP data automatically. The task comes with a list of predefined t* like CRU and with different default parameters (see blog). The PR also adds some safety checks at the calibration and computation of the mass balance to make sure there is no misused parameters (PR493). By Fabien Maussion.

• The process_cesm_data function has been split into two functions, to make it easier to run oggm with the climate of other GCM’s: process_cesm_data reads the CESM files and handles the CESM specific file logic. process_gcm_data is the general task able to handle all kind of data. process_cesm_data can also be used as an example when you plan make a function for running OGGM with another GCM (GH469 & PR582). Anouk Vlug.

• New process_dummy_cru_file task to run OGGM with randomized CRU data (PR603). By Fabien Maussion.

• Colormaps in some graphics are replaced with Hue-Chroma-Luminance (HCL) based improvements when python-colorspace is (optionally) installed (PR587). By Sadie Bartholomew.

• Added a workflow merge_glacier_tasks which merges tributary/surrounding glaciers to a main glacier, allowing mass exchange between them. This is helpful/necessary/intended for growing glacier experiments (e.g. paleoglaciology) (PR624). By Matthias Dusch.

• New oggm_prepro command line tool to run the OGGM preprocessing tasks and compress the directories (PR648). By Fabien Maussion.

• init_glacier_regions task now accepts RGI Ids strings as input instead of only Geodataframes previously (PR656). By Fabien Maussion.

• The entity_task decorator now accepts a fallback-function which will be executed if a task fails and cfg.PARAMS[‘continue_on_error’] = True. So far only one fallback function is implemented for climate.local_t_star (PR663). By Matthias Dusch.

• New process_gcm_data task to handle CMIP5 files. By Nicolas Champollion.

### Bug fixes#

• Remove dependency to deprecated matplotlib._cntr module (GH418). By Fabien Maussion.

• Fixed a bug in tidewater glaciers terminus position finding, where in some rare cases the percentile threshold was too low (PR444). By Fabien Maussion.

• Fixed a caching bug in the test suite, where some tests used to fail when run for a second time on a modified gdir (PR448). By Fabien Maussion.

• Fixed a problem with netCDF4 versions > 1.3 which returns masked arrays per default. We now prevent netCDF4 to return masked arrays altogether (GH482). By Fabien Maussion.

### Internals#

• We now use a dedicated server for input data such as modified RGI files (PR408). By Fabien Maussion.

• Test fix for googlemaps. By Fabien Maussion.

• Added a utility function (idealized_gdir()`) useful to dow flowline experiments without have to create a local map (PR413). By Fabien Maussion.

## v1.0 (16 January 2018)#

This is the first official major release of OGGM. It is concomitant to the submission of a manuscript to Geoscientific Model Development (GMD).

This marks the stabilization of the codebase (hopefully) and implies that future changes will have to be documented carefully to ensure traceability.

New contributors to the project:

• Anouk Vlug (PhD student, University of Bremen), added the CESM climate data tools.

• Anton Butenko (PhD student, University of Bremen), developed the downstream bedshape algorithm

• Beatriz Recinos (PhD student, University of Bremen), participated to the development of the calving parametrization

• Julia Eis (PhD student, University of Bremen), developed the glacier partitioning algorithm

• Schmitty Smith (PhD student, Northand College, Wisconsin US), added optional parameters to the mass balance models

## v0.1.1 (16 February 2017)#

Minor release: changes in ITMIX to handle the synthetic glacier cases.

It was tagged only recently for long term documentation purposes and storage on Zenodo.

## v0.1 (29 March 2016)#

Initial release, used to prepare the data submitted to ITMIX (see here).

This release is the result of several months of development (outside of GitHub for a large part). Several people have contributed to this release:

• Michael Adamer (intern, UIBK), participated to the development of the centerline determination algorithm (2014)

• Kévin Fourteau (intern, UIBK, ENS Cachan), participated to the development of the inversion and the flowline modelling algorithms (2014-2015)

• Alexander H. Jarosch (Associate Professor, University of Iceland), developed the MUSCL-SuperBee model (PR23)

• Johannes Landmann (intern, UIBK), participated to the links between databases project (2015)

• Ben Marzeion (project leader, University of Bremen)

• Fabien Maussion (project leader, UIBK)

• Felix Oesterle (Post-Doc, UIBK) provided the AWS deployment script (PR25)

• Timo Rothenpieler (programmer, University of Bremen), participated to the OGGM deployment script (e.g. PR34, PR48), and developed OGGM installation tools

• Christian Wild (master student, UIBK), participated to the development of the centerline determination algorithm (2014)