Which parameter keywords have been changed/updated from previous versions of AEM3D?

Question

While updating an existing AEM3D model, I have noticed that a number of parameters in the water quality configuration files have different keywords in the newer version. For example, "DONL_sedflux_max_rate" has been changed to "DONL_sedflux_coefficient" in the nitrogen.dat file and "PO4_sedflux_T_multiplier" has been changed to "temperature_PO4_sedflux_multiplier" in the phosphorus.dat file. 

Is there documentation available detailing all the revisions to help with updating my model?

Thanks

 

Answer 1

Hi Bryan

I changed the sediment flux routines to use the same functional forms (section 8.3 of the user manual) used in the rest of the code so they are now completely configurable. (I need to remove Section 8.3.2 of the manual)

The specification of parameters is therefore now consistent with other processes.  With the  μ coefficient at the front  of the equation specified with the suffix _coefficient, then parameters for individual parts of the function have the form $VARIABLE_NAME$_$PROCESS_NAME$_$PARAMETER_NAME$ 

So for sediment flux of DONL the $PROCESS_NAME$ is DONL_sedflux

μ keyword is therefore DONL_sedflux_coefficient

 

By default, it uses a temperature power equation and a Michaelis Menten Oxygen equation so the required keywords are temperature_DONL_sedflux_multiplier and  O2_DONL_sedflux_half_saturation.

 

The timing of your question is quite opportune as I’ve been making some additional changes to parameter names.  There has been some confusion with the P_C_Ratio (and N_C_Ratio) name which should specify P:ChlA ratio when simulating in ChlA units and P:Carbon when simulating in Carbon units so I’ve modified the code to allow users to specify either P_Carbon_Ratio or P_Chla_ratio.  Ycc is now carbon_chla_ratio and Internal nutrient min and max parameters such as nitrogen_min_internal are now called N_Chla_ratio_min (the user can also specify N_Carbon_ratio_min).

These changes are in the dev version of the model download.

I think these should be the only parameter changes you would need to make though there have been quite a few bug fixes since 2018.

Chris