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Generation of osm_ltlbiomass_integrated.nc forcing file for OSMOSE v3 (Update 2)

Dear Sir/Ma'am,
For the generation of biomass forcing file for OSMOSE model, most of the prior studies that I have come across utilize a physical model (like ROMS) coupled to a biogeochemical model (like NPZD). However, I would like to know if there is a possibility to incorporate satellite data (for example: satellite-derived chlorophyll) for the creation of the ltl_biomass_integrated.nc forcing file. If so could you provide some information (eg. title of the scientific paper/ names of authors) about the studies that have attempted to do so?If possible, to what extent can we utilize satellite-derived chlorophyll to generate the LTL biomass forcing file we require to run OSMOSE and what would be the expected merits/demerits for such an approach? Kindly do correct me if I'm wrong.
Kind regards,
Tarun Joseph

Hello Tarun,

We use low trophic level data from biogeochemical models because 1. it is convenient (they come as rastererized data, with no holes, etc.) 2. we are in end-to-end modelling dynamic. Nonetheless in some (most ?) cases you may not have such model outputs. And you may use any available information on the low trohic levels compartment of you ecosystem to provide to Osmose : surveys, data from litterature, or derived LTL biomass from chlorophyll data, there is no limitation as long as you are clear-headed about the pros and cons of your method and the limitations / marigins of erro, etc.

So my first reaction will be : go ahead it is a good idea ! It is all about what LTL compartment can you realistically derive from the sattelite data ? Phytoplancton undoubtedly but what about larger zooplancton ? That is when you may try to diversify your sources. Would you have any quantified information about large/small zooplancton ? Before digging the matter you must first ask yourself : given the fishes species I want to include in my Osmose model what LTL compartments are essentials ? As a last resort, Osmose allows you to specify an annual LTL biomass for a compartment you would hardly know anything about and this biomass will be distributed evenly in space and time over the year. I say last resort because such a choice is always harder to justify when it comes to publishing your configuration.

I do not have any publication in mind about Osmose and chlorophyll derived LTL biomass, though you may contact Arnaud Gruss or Morgane Travers (check first their publication for respectivelly Gulf of Mexico and Northen Channel Osmose configurations) as they were in the situation with no biogeochemical model available on their study regions.

Philippe