CyberGIS TauDEM App

The CyberGIS TauDEM App is a software service hosted at the CyberGIS Center at the National Center for Supercomputing applications at the University of Illinois. TauDEM can produce many hydrologic terrain analysis products. Using this App, users can calculate and analyze topography represented by a grid digital elevation model and produce a wide range of topographically derived hydrologic information, such as the stream network, wetness index and watersheds draining to each segment of a stream network. This app takes input from a digital elevation model in a HydroShare resource you provide and writes the calculated information back to the same resource as new files.

What can I do with this App?

The CyberGIS TauDEM app is designed for you to specify an input DEM and the product that you want. CyberGIS TauDEM takes as input a grid digital elevation model (DEM) dataset from a HydroShare resource, then based on the user selecting the output product they want, determines the sequence of TauDEM functions to run to obtain the output. The programs are run on a high performance computer at NCSA and results saved back to HydroShare. By using this app you can perform terrain analysis without having to download or install TauDEM or GIS software on your computer, or have a computer with sufficient memory and processing capacity to handle the data you want to compute. You also avoid platform compatibility limitations if your computer does not have or support the GIS functionality needed to run locally.
TauDEM provides the following capability:
  • Development of hydrologically conditioned (pit removed) DEMs using the flooding approach
  • Calculates flow paths (directions) and slopes
  • Calculates contributing area using single and multiple flow direction methods
  • Multiple methods for the delineation of stream networks including topographic form-based methods sensitive to spatially variable drainage density
  • Objective methods for determination of the channel network delineation threshold based on stream drops
  • Delineation of watersheds and subwatersheds draining to each stream segment and association between watershed and segment attributes for setting up hydrologic models
  • Specialized functions for terrain analysis, including:
    • Calculates the slope/area ratio that is the basis for the topographic wetness index
    • Calculates both the distance up to ridges and down to streams in horizontal, vertical, along slope and direct variants
    • Maps locations upslope where activities have an effect on a downslope location
    • Evaluates upslope contribution subject to decay or attenuation
    • Calculates accumulation where the uptake is subject to concentration limitations
    • Calculates accumulation where the uptake is subject to transport limitations
    • Evaluates reverse accumulation
    • Evaluates potential avalanche runout areas

Example Uses of App

You need a digital elevation model to start.  You could use your own digital elevation model data, but this example uses the resource “Onion Terrain Analysis Start” in HydroShare https://www.hydroshare.org/resource/dfc883a5d201441ba69b87486a0fc1a6/
  1. Download the contents of this resource as a zipped bagit archive, then upload the 8 files in contents into a resource that you own.  (See elsewhere for how to download and upload files to HydroShare).  This step is necessary to have this data in a resource that you own, so that the app can write result files back into it.

  2. From the resource landing page click on Open with … TauDEM CyberGIS Hydrologic Terrain Analysis App.

    This will take you to http://gwdev8.cigi.illinois.edu:8080/home/. If you are doing this for the first time and do not already have an account at CyberGIS, register for an account at CyberGIS by clicking on the Register link and entering the information requested. You will also need to authorize the app to act on your HydroShare content. This is similar to authorizing an app on a cell phone to access your data.


    If you went through the account creation steps, after creating an account you may need to close the CyberGIS browser window, return to HydroShare and at your Onion Creek Resource again click Open with TauDEM CyberGIS Terrain Analysis App to open the App from your account.

    If you receive a security certificate warning click "Continue to this website".  The configuration of certificates for secure web data transfer is not properly up to date.

  3. Log in using the account you just created. You will also need to authorize the app to act on your HydroShare content.


  4. You should get to the TauDEM CyberGIS App page.  This is designed for you to indicate the result that you want, then it will figure out what sequence of commands to run.
  5. First you need to enter an Analysis name.  Here I suggest using "dem" as this will be used as a prefix for the rasters produced.  Then you can click on the check boxes for whatever TauDEM products you want.

  6. Here we select Contributing Area Stream Raster, Stream Network and Subwatersheds, and Topographic Wetness Index.
    These are three common uses of TauDEM for DEM analysis.

  7. To learn what each product is click on the text link next to it.  This takes you to the help wiki entry for that product.


    Note that the system shows the processing sequence that is built in to get to the products you requested.  You can hover over and click on each symbol to learn about it.  In some cases you can override the inputs to be from files you loaded, rather than precomputed values.


  8. Next click Parameters at the top.  Here you get to specify input parameters.  For Aread8 set the o.shp file to Outlet.shp.  For Streamnet set the src file to Contributing Area stream raster (that will be calculated)  and o.shp to outlet.shp. Adjust the channelization threshold to 10000.

    You do not need to adjust any other settings.

  9. At the top click on Review then submit.

    You should see an animated hammer indicating that the job is submitted.
     

    As your job progresses through the system, the symbol will change to indicate progress:
     

  10. Once your job is done, select it (click on it) in the My Analysis list and click Load to see your results on the map.


    Then right click on layers to show on the map.
    This shows the stream network delineated.

App Output

Once the App has completed return to HydroShare and refresh the browser for the HydroShare resource.  You will see that multiple TauDEM results files have been added back into your resource.  

These are named with the analysis provided to CyberGIS “dem” and follow the TauDEM suffix naming convention given in http://hydrology.usu.edu/taudem/taudem5/help53/GridDefinitionsAndNamingConventions.htm.  The specific outputs of interest are
  • demnet.shp (and its parts demnet.shx, demnet.prj, demnet.dbf) that are the delineated stream network
  • demw.tif  A raster file with the subwatersheds draining to each stream link
  • demtwi.tif  Raster file with topographic wetness index.
These files can be downloaded for further work in a GIS, or visualized in the HydroShare GIS app.

Suggestions to learn more

Links to sample outputs available as Resources in HydroShare

The resource “Onion Watershed Delineation Results”  https://www.hydroshare.org/resource/d6ae529dadf94f2eb8357ac5de9db941/ gives results from the example above.

Credits, Authors, Contributors and Contacts

  • David Tarboton, Utah State University
  • Shaowen Wang, University of Illinois
  • Yan Liu, University of Illinois
  • The CyberGIS TauDEM App is part of HydroShare + CyberGIS interoperabiity developed with support from a supplement to the CyberGIS award (ACI 1047916)
  • TauDEM has been developed over many years with support from sources given in the TauDEM website http://hydrology.usu.edu/taudem/taudem5/acknowledge.html