Configuring Vertical Profiles
A vertical profile refers to the representation of a parameter or constituent at various depths within a water body, such as a river or lake. It is helpful for understanding the stratification of the water column, allowing an engineer to assess data variations throughout the water body. For example, vertical profiles of water temperature help identify thermal stratification, which is the layering of water with different temperatures. In many lakes during summer, distinct layers of warm surface water (epilimnion) may be observed, a thermocline where temperature decreases rapidly with depth, and colder deep water (hypolimnion). Other parameters of interest typically include salinity, dissolved oxygen, and various water quality constituents. This blog provides guidance on how to process data for comparison to the model results in EEMS.
An example of a water temperature vertical profile is shown in Figure 1.
It is necessary to preprocess data before importing them into EEMS. You can process data using Excel or a script to write the data in a format compatible with EEMS.
Format for Vertical Profile Data
When there is data from multiple stations, it is advised to make a data file for each station. The file extension must be *.dat and its format should be as shown in Figure 2.
The first line contains the title (e.g., station name and location coordinate). This field is ignored when EE reads the file.
The second line contains the number of data points on the vertical profile (i.e., 10); Date (Gregorian) (i.e., 30-Apr-2012) and time (i.e., 14:00)
The third line contains the water depths from the surface at the point where the data is collected along with the vertical profile. The unit of depth must be in meters to be used in EEMS.
The fourth line contains observed constituent values corresponding to each depth in the third line. The unit must correspond to the model units.
Lines 2 to 4 are repeated for other profiles.
Configuring Vertical Profile Data in EEMS
To compare model results with measured data, first select the Vertical Profiles under the Model Analysis as shown in Figure 3. RMC on the Vertical Profiles, then select Define Calibration Series. The Model Calibration: Vertical Profile Comparisons form will be displayed as shown in Figure 4.
The # of Comps is the number of data files we want to compare (number of calibration stations). This field will initially be “0” when starting the model-data linkage process. Enter the number of stations here, then press the Enter key. EE will create a line in the table for each station.
RMC on the cells in the table to open the Station Information form to define model parameters and data series file path. An example of the completed station information is shown in Figure 5. Fill in the station ID, coordinates, and parameter. Also, provide the path to the data file. Complete this form for each station before operating the model calibration feature (Figre 6 shows a completed list).
The Julian Date Offset is used when Julian dates have been used in the data files rather than Calendar dates. This offset allows the user to add the specified number of days to the Julian dates.
After completing the configuration, click the Plots button to show the vertical profile comparison. Figure 7 shows a comparison of observed and modeled water temperature vertical profiles.
EE allows the user to generate vertical profile plots automatically at the end of each model run. Refer to the Auto generate plots page in our Knowledge Base to learn how to do this.
Do you want to try these options for yourself? You can start by downloading EEMS, activating the free demo mode, and then running our demonstration models. To see these features in action, head over to our YouTube page.
Please get in touch with us if you have any comments or questions. For more information on EFDC+ capabilities, contact the DSI team today.
