Oluf Jessen

Hi Chris,

I believe this is a MIKE 11 issue, and you should probably try to post it on the MIKE 11 forum. I don't have the answer to your question, but if you don't get any reply to this very specific questions, you could also try to contact mikebydhi@dhigroup.com as they could forward you to one of the developers who would know the answer to your question.

If you get an answer then please copy the answer into this post. :-)

Best regards
Oluf (DHI)

Hi,

In the MIKE ZERO Toolbox there are tools for converting ESRI ASCII raster grids to dfs2 files, meaning convertion between ESRI raster format and DHI raster format. If you want to add the time dimension, by getting a time series from a time varying grid, then you would have to use the DHI SDK for reading and writing DHI files (dfs files). Look at http://www.yourepeat.com/watch/?v=q3pfVKRgI6g for more information.

Oluf

Hi,
Based on your description you should try and reduce the WB error. An error of 3% on average might be ok, but the error during the high intensity rain events is too high.

Some of the issues to look at:
- Look into the WM_Print.log file to evaluate if the maximum iteration is exceeded. If so try to adjust the SZ and UZ max time step so they are closer. The SZ max time step should not be more than 4 times the UZ time step.
- Evaluate the precipitation time step control, and try reducing the values as this will force additional time steps during rain fall events – this will increase the total computational time but might reduce the WB error
- Evaluate the spatial extent of the error, and if it’s mainly on a single soil type or if it’s distributed across all soil types. This might lead to an evaluation of the soil parameters if it’s mainly on a single soil type.

Oluf (DHI)

Hi Sofie

Could you post a screen dump of your problem?

Oluf (DHI)

Hi,

I'm not aware of any existing tools released by DHI that could do this.

In order to do this you could make a small tool using 1) a library for reading the netcdf files, and 2) the DHI SDK for writing the data into a time varying dfs2 file.

For reading the netcdf files you could use the Gdal open source library (http://www.gdal.org/) for converting each time step in the netcdf file to an ASCII grid file, and then converting the grid files to a time varying dfs2 file using the DHI SDK (see example at http://www.youtube.com/watch?v=q3pfVKRgI6g).

There might be other ways of doing this, but this is one way we have used before.

BR
Oluf (DHI)

Hi,

The error message basically tells you that AutoCal was not able to calculate the statistics from the model. There could be a number of reasons, and the first issue would be to verify that the model terminates correctly. I would recommend you to first try and execute the model in the “Model_Process1” folder without using AutoCal to make sure that it terminates correctly, and that it is not executed with an error. Next make sure that it generates the dfs0 files that you are using to calculate the statistic, and that the files contains actual values.
If this works then look inside the log files from AutoCal and evaluate if it calculates the objectives or if some of the values are Nan. If it still gives problems I would recommend you to contact the support at mikebydhi@dhigroup.com as they would be able to debug the error.

Oluf (DHI)

Hi Julia
This is an interesting issue and I have some suggestions but there might be better solutions from others.

1. As you don’t have a river in your setup you don’t have the option of selecting the total outflows from all the catchments. There are two solutions:
              a. Include a river in your setup (MIKE 11 model). The river should receive the outflow from all the catchments and the most downstream node would then contain the total flow (make a detailed timeseries output for this node). Use a routing method and a very low leakage coefficient if you don’t want to lose any water from leakage from the stream (adjust the parameter if that’s the case). Adjust the routing parameters to include any time lag between the outflows from the different catchments.
            b. Make a small script (C# code) that is executed by AutoCal just after the MIKE SHE simulation is done. The tool should read the flow from each of the sub-catchments (from the MIKE SHE result file) and sum the values into a new time series file. The new time series file (dfs0) should then be used in AutoCal for the simulated values. For help making the code please look into the software development kit (SDK) which comes with the 2014 version. It includes examples of how to make a tool for reading and writing dfs files.

2. You are correct that there is not an option for monthly results, and using the hours is not a good option especially if you have a long simulation. I would recommend keeping your results in daily time steps and making a tool for converting the simulation results to monthly before doing the stat.

I hope this helps you on the way, but there might be other users with better suggestions.
?
Best regards
Oluf (DHI)

Hi,

The error "Crop stages for rotation scheme no. 1 all all before start of simulation" indicates that the first crop under "Landuse/Vegetation" has a start and end date that are before the simulation start. Meaning that the whole crop development of the first crop (named as rotation scheme no. 1) are before the simulation period. The same is the case with crop 1,2,3 and 4.

Note that you your crop development could start before and end after your simulation period but you need to have crop development within your simulation period. Check start date for the crop and the number of days specified for the crop development as it ends up with a crop development before your simulation period.

Best regards
Oluf (DHI)

Hi,
In your model setup, under Computational layers definition, you specify a  ”Minimum layer thickness”. This parameter specifies the minimum thickness of the computational layers, and if you specify a computational layer with a thickness less than the specified, the model will adjust the layers downwards until the minimum thickness is applied.

Note: If you use the option “- Computational Layers defined by Geological Layers” the model adjust your geological layers (corrections are done on your geology). If you use the option for “Explicit definition of lower levels” the adjustment is done on your calculation layers and the geology is not altered.

I would recommend you to use the option of “explicit definition of lower levels” as any adjustment then will be done on the calculation levels and not the geological levels. Also look into which minimum thickness you need in order to resolve your flow pattern in the area. Using very thin calculation layers could make it more difficult for the solver to find a solution, but it could also in some cases be important to have this fine resolution of your flow patterns.

Best regards
Oluf - DHI

Hi Ben

As I understand you have a primary sand aquifer and three surface catchments within the aquifer. One of the main issues when setting up a model is to get well defined boundary conditions. In a case like yours where you most likely will have groundwater flow across the boundaries for the surface catchments I would recommend you to model all three catchments within your model domain, as this will enable you to have well defined groundwater boundaries at the catchments borders. I don’t know your area, but it might be that you could assume no-flow boundaries at the east, north and west, you then need to figure out how to handle the southern boundary – use observed data, river stages, or based on assumptions of the conceptual hydrological settings. If your focus area is smaller than the three catchments then you could use your regional model to generate boundary conditions for a smaller sub-model. This would be a typical approach when dealing with a large area. So with respect to your question, it’s possible to model multiple catchments within a single model, and unless you have knowledge of the groundwater flux between the catchments I would recommend you to model all the catchments in the same model and use this approach to get a better handle of the boundary conditions. 

Best regards

Oluf - DHI