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The meaning of 'ltl_biomass_pred'

Dear Sir,
Recently I am working on the OSMOSE model for my project, however, I feel confused that the meaning of 'ltl_biomass_pred' which is in the file 'osm_ltlbiomass_integrated.nc'. Would you tell it in details and more information about LTL.
Thanks,
Lei Xing

Dear Lei Xing,

I agree that this is confusing to find this variable ltl_biomass_pred variable in the LTL forcing file, I should have removed it actually because it is of no use. Variable ltl_biomass is the only variable that is read by Osmose.

The Osmose OSM default configuration is based on the Benguela ecosystem. The original Benguela configuration was forced by ROMS-NPZD outputs, which are large NetCDF files. I did not want to include the original NetCDF files because that would be to heavy to download. Instead I provided a NetCDF file that is already spatially interpolated and vertically integrated, which is much lighter.

How did I generate this osm_ltlbiomass_integrated.nc NetCDF file ? I ran the Benguela configuration for one year, with the original ROMS-NPZD forcing, and I enabled the output file 'output.spatial.ltl.enabled'. This output provide a NetCDF file with two variables : ltl_biomass and ltl_biomass_pred. ltl_biomass_pred is the LTL biomass left in the system after the predation process. ltl_biomass is the LTL biomass before predation, which is the biomass provided by the ROMS-NPZD files, but interpolated on the Osmose grid and vertically integrated. And this is the file I used to force the OSM default configuration. I should have deleted the unecessary variable ltl_biomass_pred, but I forgot to do so.

Cheers, Philippe