intro story Coast / Estuary

Coast / Estuary

Coastal systems are among the most dynamic physical systems on earth and are subject to a large variety of forces. The morphodynamic changes occurring to coastlines worldwide are of great interest and importance. These changes occur as a result of the erosion of sediments, its subsequent transport as bed load or suspended load, and eventual deposition. 
Estuaries are partly enclosed water bodies that have an open connection to the coast. Estuaries generally have one or more branching channels, intertidal mudflats and/or salt marshes. Intertidal areas are of high ecological importance and trap sediments (sands, silts, clays and organic matter).
Within the Delft3D modelling package a large variation of coastal and estuarine physical and chemical processes can be simulated. These include waves, tidal propagation, wind- or wave-induced water level setup, flow induced by salinity or temperature gradients, sand and mud transport, water quality and changing bathymetry (morphology). Delft3D can also be used operationally e.g. storm, surge and algal bloom forecasting. 
On this discussion page you can post questions, research discussions or just share your experience about modelling coastal and/or estuarine systems with Delft3D FM. 




Sub groups
D-Flow Flexible Mesh
Cohesive sediments & muddy systems



Message Boards

Light extinction due to DOC

Ingrid Holzwarth, modified 6 Years ago.

Light extinction due to DOC

Youngling Posts: 10 Join Date: 10/24/12 Recent Posts
Dear Delwaq-Forum,

I use the DYNAMO-module to simulate algae growth and activate the radiation-limitation function. Therefore, the total extinction coefficient has to be calculated.

If I use th GUI, I can choose different specific attenution coefficients which are multiplied by the concentration of the specific substance (e.g. Diatoms or POC1) to result in a contribution to the total extinction coefficient.
However, I don't find a possibilty to choose a specific coefficient for DOC and my results for ExtVlODS (which should contain the partial attenuation due to DOC) contain only zeros.
Do I have to activate this part separately from the other partial attenuations?

Best regards,
Anonymous Anonymous, modified 6 Years ago.

RE: Light extinction due to DOC

Jedi Master Posts: 333 Join Date: 7/30/20 Recent Posts
Dear Ingrid,
I was also, surprisingly, not able to activate the extinction coefficient for DOC using the GUI. I'll keep looking because it has to be there, somewhere, in the process library of DelWAQ.

In the meantime, it is possible to force it. You should add it by manually editing your input file (in block 7), with something like:
You can then check in the LST and LSP-files that it is read and activated correctly, and then in your output file that is indeed contributing to ExtVLODS.

Just as a reminder, be aware that every time you save your work with the GUI, the input file will be overwritten (and your manual changes will be erased).

Hope this helps,
Michel Jeuken, modified 6 Years ago.

RE: Light extinction due to DOC

Jedi Knight Posts: 154 Join Date: 1/21/13 Recent Posts
Hi Ingrid,

I see no reason why it should be an hidden option, so I changed some flags. This version of the proc_def should make it available in the PLCT. You can replace it in your Delft3D installation, usually somewhere in c:\Program Files (x86)\Deltares\Delft3D 4.01.00\win32\waq\bin\.


P.S.: Another work around (in case you need an other hidden parameter or output) would be to add the parameter to the sub-file, see an example below. This way you can still use the delwaq GUI. However, you can't load the substance file into the PLCT, so if you update your model with the PLCT, you need to add your manual changes to the sub-file again.

parameter 'RcMrtEColi'
description 'first-order mortality rate EColi'
unit '(1/d)'
value 0.8000E+00