Posted Sun, 15 May 2016 13:35:26 GMT by Frederick Mashingia
I am new to Mike family models. I have converted my ArcGIS DEM grid to dfs2 using the Grid2Mike tool but when I am loading it under topology menu, it is complaining that NO VALID ITEMS. Any idea?

Thanks,

Fredrick
Posted Thu, 19 May 2016 01:50:13 GMT by Frederick Mashingia
RESOLVED by changing the properties after conversion.
Posted Thu, 09 Mar 2017 20:33:17 GMT by sweetguo1989
Hi Fredrick,

I has the same issue when upload DEM grid under topography menu. Could you please tell me what kind of specific properties you change after conversion?

Thank you,
Tian
Posted Fri, 10 Mar 2017 10:52:02 GMT by Douglas Graham
Hi Tian,
Each of the data items in MIKE SHE require a specific Item Type. This is part of the overall error checking the user interface. The Item type for topography is "Elevation". This can be changed by opening the dfs2 file in the Grid Editor, and selecting Edit/Items... from the top menu.

Hope this helps.
Douglas

Posted Sat, 11 Mar 2017 02:49:56 GMT by sweetguo1989
Hi Dr. Graham,

Thank you very much for your suggestions. Problem has been solved for df2 DEM data. I am a newbie to MIKE SHE and have some more questions about my MIKE SHE model.
1. I have three rainfall gauge stations near my watersheds. I generated a Thiesson polygon for my watershed and converted it into a raster and then to a ASC file. I got error when I used Grd2MIke to convert ASC to dsf2 file. It said "Error reading Input File: ". I have checked ASC file and did not figure out what is wrong with it. And I also tried Time Series Batch Conversion but it has difficulty in reading column for date and time. So what is the best approach to prepare precipitation input from several stations for watershed? Could you please share some examples or template for it (before converted to dfs2)?

2.  I would like to simulate streamflow, and TN and TP at the watershed outlet. And I opened MIKE SHE flow model. BUT i did not found interface to upload land use, temperature and soil inputs to a MIKE SHE flow model. So should I create a MIKE SHE .uzs and .etv model and upload land use, temperature and soil inputs in these models, and then link it with .she model? What is the appropriate way to handle it?

Thank you again and your responses will be greatly appreciated.
Tian
Posted Tue, 14 Mar 2017 08:36:13 GMT by Douglas Graham
Hi Tian,

1. If you have a Theissen polygon and a dfs0 time series of precip for each polygon, then you don't need to convert this to a grid. You can simply input the Theissen polygons (as a polygon shp) and then add the dfs0 time series file as the input for each polygon.
In the main precip dialog, chose the polygon option. Then, a subtree item should be added for each polygon, where you can specify the dfs0 file. The only requirement is that the polygon file needs to have the same GIS projection as the Model Domain and Grid.

2. To make the land use option available, you have to turn on UZ and ET in the main Simulation Specification dialog. Then, you should have a data tree item called Land Use. Here you can specify a polygon file or a dfs2 grid file with the vegetation distribution. For each vegetation type, you need to specify a leaf area index and a root depth. These can be specified as a time series directly, or via the vegetation database (.etv file).
Defining the soil distribution is the same. Then for each soil zone, you have to specify a soil column and a vertical discretization. For the soil types, you need to create a .uzs file. I have attached a .uzs for the standard UNSODA soils.

3. Temperature is more complicated. Air temperature is used for the snow melt calculation and is defined under Climate when you have turned on the snow melt. But, soil temperature is derived from the air temperature and is part of the water quality model.

I hope this helps.
Douglas
Posted Tue, 14 Mar 2017 17:24:19 GMT by sweetguo1989
Hi Douglas,

Thank you very much for your suggestions. I really appreciate it.
1. I have added precipitation data successfully through Theissen polygon and dfs0 time series.

BTW, when I tried to use Preprocessing Temporal Data to prepare precipitation input, I have to select a dfs2 file for "Model area defined by". Then I tried to added my topography dfs2, but it did not work because the item type is not "Bathymetry". So how can I deal with this problem if I would like to use this tool?

2. For land use, I convert NASS crop data layer into ASC and then converted to dfs2, but when I added it into land use interface, I do not know which item type I should choose. I did not find a type about land use or vegetation.

3. We only have max and min temperature for climate stations. So should we do not calculate snow melt, since we do not have an instantaneous air temperature?

Thank you again and your responses will be greatly appreciated.
Tian
Posted Thu, 06 Apr 2017 11:56:08 GMT by Douglas Graham
Hi Tian,
1. you can change the Item Type in the Grid Editor from Elevation to Bathymetry.
2. the land use has to be in the Item Type of Grid Codes. Then each unique Grid Code is assigned a Leaf Area Index and Root Depth as a constant value or a time series, or linked to an item in the vegetation database.
3. you could create an instantaneous temperature dfs0 file with your min temperature at 03:00 and your max temperature at 13:00.
Douglas

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