Which is the proper variable of Sea Ice freshwater flux into the Ocean

Hi Folks,

I am interested in the sea ice freshwater flux into the ocean of ACCESS-CM2 historical data. I grabbed some output variables from CMIP6. But I am not sure which is the proper one, they seem similar.

‘siflfwbot’:

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‘fsitherm’:

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‘sidmassth’:

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Even ‘fsitherm’ and ‘siflfwbot’ have the same standard name, the data are different.
I am not sure which one contains the salty part, or total freshwater, or freshwater compensated by salt. I prefer to use the freshwater flux compensated by salt. :slight_smile:

Many thanks

Hi Zijin, I am most familiar with the output from the CICE model so the sidmassth variable called dvidtt in access-om2 output files its the rate of change of the ice volume/mass when multiplied by density in this case due to the ice thermodynamic changes and is not what you are looking for.

Siflwbot is the the fresh water directly from the ice model output.

fsitherm is the melt term in MOM5 code “melt = -Ice_ocean_boundary%salt_flux(i,j)*ice_salt_concentration_r”

so hope that explains the differnce between these two terms. Its never in my checks been a perfect match due to accumulative round off error over monthly averages.

We left both measures in so user could decide which one they wanted to use based on their usual approach.

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Thank you, Siobhan

I want double check that siflwbot is a freshwater flux and fsitherm is a water flux with salt? Or fsitherm is also a freshwater flux. I didn’t see any salt flux variable in the output file, so I guess it may have calculated the salt in the output.