Snow on Sea Ice (snow)

Warren99 & AMSR2 Monthly Climatology (clim_w99amsr2)

The monthly Warren99 and AMSR2 snow climatology provides monthly snow depth and density values for the Arctic winter months from October through April.

Note

This auxiliary dataset only provives snow information for sea ice in the Northern Hemisphere.

Configuration Parameters

The Auxiliary Dataset ID is snow:clim_w99amsr2 and the configuration in the auxiliary data definition of the Level-2 processor definition file is:

- snow:
    name: clim_w99amsr2
    options:
        daily_scaling: True
        fyi_correction_factor: 0.5
        exception_on_error: False

Options

  • daily_scaling: Flag, when set to True, will scale the monthly climatology to daily values by linear interpolation of the monthly values based on the current day. The monthly mean values are defined as the climatology on the 15th day of the respective month, with the exception of October (1st day) and April (last day).

  • fyi_correction_factor: Factor to correct the snow depth values for FYI (requires sea_ice_type as input. E.g. a factor of 0.5 halves the climatological snow depth values.

  • exception_on_error: Flag, when set to True, will raise an exception if the auxiliary dataset is not available for the requested time period. If set to False, the processor will continue without the auxiliary dataset and all output is set to NaN. An error will be logged in this case.

Data Variables

The following variables are returned from this dataset:

  • snow_depth: Snow depth on sea ice in meters

  • snow_depth_uncertainty: Uncertainty estimate for snow depth in meters

  • snow_density: Snow density on sea ice \(\,^{kg}\!/\!_{m^3}\)

  • snow_density_uncertainty: Uncertainty estimate for snow density in \(\,^{kg}\!/\!_{m^3}\)

Data Source and Storage

Data files are available on the ftp of the Alfred Wegener Institute and need to be downloaded into the directory defined in the local_machine_def.yaml file under the key auxdata_repository.snow.climatology_w99amsr2.

ftp://ftp.awi.de/sea_ice/auxiliary/snow_on_sea_ice/w99_amsr2_merged

(FTP settings: anonymous login, encryption disabled)