GOTM

... now with ice ...

Karsten Bolding

February 10, 2020


Updated from 2019-08-07. Ice module is ready for production runs.

The use of submodules has made it much easier to integrate external projects without major risk of side effects.

CMake configuration

This blog contains information that goes along with this.

The inclusion of ice follows the method used to include FABM. A CMake variable GOTM_USE_STIM can be on or off - default will be off. As STIM can only be configured as a submodule no further configuration is necessary.

STIM provides a frame-work for including a number of different simple ice models. Presently two different models are fully working - and a third one is on progess. The STIM page will contain more information and hopefully be expanded in the future.

Run-time configuration - YAML only

The configuration is very sipmple and takes only 3 variables. Se below:

  ice:
    ice_model: 0                     # [0=None, 1=Lebedev (1938), 2=MyLake, 3=Winton; default=0]
    Hice: 0.0                        # total ice thickness [m; default=0.0]
    ocean_ice_flux: 0.0              # heat flux from ocean to ice [W/m2; default=0.0]

valid values for ice_model is 1, 2, (3). Hice is the initial ice thickness. The ocean_ice_flux is a non-resolved flux of heat from ocean water to the ice.

And additional option might be added to use the old GOTM implementation - even in the case GOTM is compiled with support for STIM.

ice:
   time_unit: hour
   time_step: 24
   sync_interval: 0
   time_method: 1
   variables:
      - source: airt
      - source: ice/*

A simulation example

Below is shown 7 year simulation with all 3 different ice models compared to observations from the Northern Baltic Sea. Ice thickness data provided by Adolf Stips, JRC.