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Model Formulation & Parameters / Re: Estuary migration
Last post by YUROK1 - July 14, 2015, 01:43:42 PM
After closer inspection the grey lines within the Riverine tidal polygon are actually strips of Estuarine polygons. The model is suggesting upriver/inland migration of the estuary but seems to be confused possibly by an adjacent side channel, thus causing a strange dynamic. I am not sure why upper boundary of the Riverine Tidal polygon has not migrated upriver/inland? Any suggestions to confirm or remedy this issue would be appreciated.
Model Formulation & Parameters / Re: Emergent Coast
Last post by YUROK1 - July 14, 2015, 01:08:33 PM
Perhaps you can reference a page number? The reason I asked is that the Tech doc states:

"Aggradation, the creation of land or drying of wetlands when sea levels fall or when accretion rates exceed sea levels, is not included in the current implementation of SLAMM 6. (page 20)

I wanted to make sure that in the case when sea level is falling due to an outpacing rate of uplift (using a negative historical trend value in place of a raster) , that the model will run. 

Model Formulation & Parameters / Estuary migration
Last post by YUROK1 - July 14, 2015, 12:40:09 PM

In our recent model run the SLAMM outputs for Estuarine and Riverine Tidal  polygons are showing no deviation from existing conditions under a A1B max at 2100 and 2175. Shouldn't  these boundaries be moving inland? What appears to be modeled are grey striations (multiple lines) within the Riverine Tidal polygon, more so at 2100. Is this a glitch in the model?
Model Formulation & Parameters / Re: Model calibration
Last post by Beneke - July 14, 2015, 11:21:09 AM
So looking at the output excel file would you be able to tell me if it appears to be calibrated?
Model Formulation & Parameters / Re: Model calibration
Last post by marco.propato - July 14, 2015, 11:16:24 AM
Tidal flat is coming from the conversion of low regularly-flooded marsh. So, this may be an issue of your marsh elevations that are too low with respect to the modeled tides. Or maybe from satellite images these areas are actually tidal flats ....
Model Formulation & Parameters / Re: Tidal Flat accretion rate ...
Last post by Ibe - July 14, 2015, 11:03:00 AM
Yes, predicting too much TF in the future.
Model Formulation & Parameters / Model calibration
Last post by Beneke - July 14, 2015, 10:56:09 AM
I've run several successful "test" scenarios and now I'm trying to make sure that SLAMM is calibrated properly before I continue. I understand that some SLAMM Categories may more uncertainty that others. For example, -Larger in tidal flat and beach due to uncertainty in land/water interface (from presentation by Amy Polaczyk, 10/22/13) this would explain one of the four unexplained major changes from initial condition and Time zero.
I have attached an excel file with these areas highlighted in yellow. Could you tell me if the other SLAMM Categories could also see a major change between initial condition and Time Zero?
I am still confused on what is the problem you are having. Are you predicting too much TF in the future? Or at time zero?

If it is at time zero, then the conversion to TF is not controlled by accretion but by the fact that your marsh elevations are initially too low with respect to the modeled tides and thus the areas are converted to TF.

If it is in the future, it all depends on the rate of SLR and time horizon. If SLR is not so high then TF will not convert to water fast enough. TF looses elevation at a rate of (BSR-SLR) mm/yr and normally converted to open water when it falls below -1 HTU (but you can change it if you think it is not corresponding to your study area).

Model Formulation & Parameters / Re: Tidal Flat accretion rate ...
Last post by Ibe - July 14, 2015, 08:46:06 AM
I am getting more TF which, as per documentation, is controlled through beach sedimentation. So I went on to change beach sedimentation rate to indirectly change TF accretion rate. But it seems that those two are not interlinked that way.
So if I have to reduce TF then what do you suggest I should change in parameter sheet I provided. Please suggest. Thanks.
I am not sure I understand the question.

BSR controls  sedimentation rate of TF and beaches, while marshes are controlled by separate accretion rates values. So there is no built-in connection between the rate marsh and TF/beaches accrete. 

Maybe you meant asking if you could assign different sedimentation rates for TF and beaches. This unfortunately can only be done through modifying the function TSLAMM_Simulation.TidalFlat_Sed in the source code. Hopefully in the future, a NEW SLAMM version will have this option.
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