- oggm.shop.its_live.velocity_to_gdir(gdir, add_error=False)¶
Reproject the its_live files to the given glacier directory.
The data source used is https://its-live.jpl.nasa.gov/#data Currently the only data downloaded is the 120m composite for both (u, v) and their uncertainty. The composite is computed from the 1985 to 2018 average.
Variables are added to the gridded_data nc file.
Reprojecting velocities from one map proj to another is done reprojecting the vector distances. In this process, absolute velocities might change as well because map projections do not always preserve distances -> we scale them back to the original velocities as per the ITS_LIVE documentation that states that velocities are given in ground units, i.e. absolute velocities.
We use bilinear interpolation to reproject the velocities to the local glacier map.
If you want more velocity products, feel free to open a new topic on OGGM’s issue tracker!
where to write the data
also reproject and scale the error data
- Files written to the glacier directory:
A netcdf file containing several gridded data variables such as topography, the glacier masks, the interpolated 2D glacier bed, and more.