Closed danibodc closed 2 years ago
I have relayed this question to our experts on the modelling team - stay tuned for a response when they get back to me.
Modelling team need to have a think about this one: response still pending...
Hi Dani, this is the response I got back from the modelling team on this one:
Including the sinking velocity, particle size, the ability to be resuspended or even how we use them in model (e.g. released from catchments, initialised to zero etc.) is non-ideal as they could limit future use.
At the risk of being ambiguous, we could use:
Concentration of particles (size class/minerology) per unit volume of the water body by model prediction.
Dust - particles (non-carbonate, very fine) Gravel-carbonate - particles (carbonate, very coarse) Gravel-mineral - particles (non-carbonate, very coarse) Mud-carbonate - particles (carbonate, fine) Mud-mineral - particles (non-carbonate, fine) FineSed - particles (non-carbonate, fine) Sand-carbonate - particles (carbonate, coarse) Sand-mineral - particles (non-carbonate, very coarse)
Also, all particles have concentration in the sediments that is by volume of (sediment?) space. In our output files this is Dust_sed etc. We only do this in the output files because the sediment grid is different to the water column grid. Dust and Dust_sed are actually the same entity in different locations.
I imagine the binary carbonate vs non-carbonate aspect should be fine - is the 'very coarse', 'coarse', 'fine', 'very fine' gradient usable?
On reflection, I think that if "dust" "gravel" "mud" "sand" "fine sediment" "sand" are terms defined as part of well known scales like e.g. Wentworth then we should keep these terms instead of very fine, fine, coarse, very coarse, unless of course the latter can be referred to a standard definition. For examples of scales see e.g. https://en.wikipedia.org/wiki/Grain_size
I agree, we can get rid of the modifier "very". The international classification as presented in your link [https://en.wikipedia.org/wiki/Grain_size] is close to what we use in the model, though it does not map one to one. We have Dust and FineSed missing from the classification. Another point to mention is that sediment classes in the code are defined by the settling velocity (m/s) and the concentration (kg/m3). The size attribution is somewhat a secondary property associated with the sediments of a particular class (settling velocity) This secondary attribute is to describe further characteristics of these sediments (but it is not used directly during the simulation).
Please see the below for our proposed terms and the physical entity size class (S29, S19) definitions. If this could be reviewed and any feedback passed on that would be great.
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CSIRO parameter | BODC pref label | BODC S29, S19 definition -- | -- | -- Dust (model: 'Dust', sensor: '', standard: ''') | Concentration of particles (dust) per unit volume of the water body by model prediction | Very fine particles of powdery solid matter with very slow settling velocities in air and water. FineSed (model: 'FineSed', sensor: '', standard: ''') | Concentration of particles (fine-grained sediment) per unit volume of the water body by model prediction | Fine grained particles of unconsolidated solid matter that can be comprised of sand, silt and clay particles of generally less than 2mm diameter. They can be transported by the action of wind, water, ice or gravity. Mud-carbonate (model: 'Mud-carbonate', sensor: '', standard: ''') | Concentration of particles (mud carbonate) per unit volume of the water body by model prediction | The carbonate fraction of fine grained particles of cohesive or non-cohesive solid matter comprised of mainly silt and clay. Mud-mineral (model: 'Mud-mineral', sensor: '', standard: ''') | Concentration of particles (mud mineral) per unit volume of the water body by model prediction | The non-carbonate fraction of fine grained particles of cohesive or non-cohesive solid matter comprised of mainly silt and clay. Sand-carbonate (model: 'Sand-carbonate', sensor: '', standard: ''') | Concentration of particles (sand carbonate) per unit volume of the water body by model prediction | The carbonate fraction of medium-sized particles of granular solid matter. Sand-mineral (model: 'Sand-mineral', sensor: '', standard: ''') | Concentration of particles (sand mineral) per unit volume of the water body by model prediction | The non-carbonate fraction of medium-sized particles of granular solid matter. Gravel-carbonate (model: 'Gravel-carbonate', sensor: '', standard: ''') | Concentration of particles (gravel carbonate) per unit volume of the water body by model prediction | The carbonate fraction of large particles of granular solid matter. Gravel-mineral (model: 'Gravel-mineral', sensor: '', standard: ''') | Concentration of particles (gravel mineral) per unit volume of the water body by model prediction | The non-carbonate fraction of large particles of granular solid matter.
In relation to the following Parameter Names (CSIRO primary keys 18-25):
Dust (model: 'Dust', sensor: '', standard: ''') FineSed (model: 'FineSed', sensor: '', standard: ''') Gravel-carbonate (model: 'Gravel-carbonate', sensor: '', standard: ''') Gravel-mineral (model: 'Gravel-mineral', sensor: '', standard: ''') Mud-carbonate (model: 'Mud-carbonate', sensor: '', standard: ''') Mud-mineral (model: 'Mud-mineral', sensor: '', standard: ''') Sand-carbonate (model: 'Sand-carbonate', sensor: '', standard: ''') Sand-mineral (model: 'Sand-mineral', sensor: '', standard: ''')
We propose to model the terms in the following format: Concentration of particles (size class) per unit volume of the water body by model prediction.
The physical entity 'particles' is defined in S29, which is a concatenation of an S18, S19, and S20 term. Traditionally we have specified a size range of particles in micro-metres e.g. 'particles (16000-22000um)'.
However, here we could include info on the sinking velocities mentioned in the 'Description' tab of the spreadsheet, copied below:
Dust - Very small sized, re-suspending particles with a sinking velocity of 1 m d−1 and mass-specific optical properties based on observations in Gladstone Harbour. FineSed - Identical to Mud-mineral, except that it is initialised to zero in the model domain, and enters only from the catchments. Gravel-carbonate - Large, non-resuspending particles. Gravel-mineral - Large, non-resuspending particles. Mud-carbonate - Small sized, re-suspending particles with a sinking velocity of 17 m d−1, and mass-specific optical properties based on observations of suspended carbonates at Lucinda Jetty. Mud-mineral - Small sized, re-suspending particles with a sinking velocity of 17 m d−1, and mass-specific optical properties based on observations in Gladstone Harbour. Sand-carbonate - sized, re-suspending particles with a sinking velocity of 173 m d−1 and mass-specific optical properties based on observations of suspended carbonates at Lucinda Jetty. Sand-mineral - Medium sized, re-suspending particles with a sinking velocity of 173 m d−1 and mass-specific optical properties based on observations in Gladstone Harbour.
To differentiate between the mineral and carbonate versions, the below is an example of how we could possibly structure the S29s: Dust - particles (sinking velocity 1m d-1) Gravel-carbonate - particles (carbonate, non-resuspending) Gravel-mineral - particles (mineral, non-resuspending) Mud-carbonate - particles (carbonate, sinking velocity 17m d-1) Mud-mineral - particles (mineral, sinking velocity 17m d-1) FineSed - particles (mineral, initialised to zero, sinking velocity 17m d-1) Sand-carbonate - particles (carbonate, sinking velocity 173m d-1) Sand-mineral - particles (mineral, sinking velocity 173m d-1)
Is this ok? Is this too specific to ensure re-use? Should we include the 'Sand', 'Dust', 'FineSed', etc instead? How would we differentiate between 'FineSed' and 'Mud-Mineral'?