Precise Computation and Visualization

Rigorous practices for minimizing bias in field measurements must be matched by equal rigor in the management of the data once it enters the AQUARIUS System.   For time series datasets there are four critical pieces of meta-data: Parameter, Units, Interpolation Type, and Time Zone.

AQUARIUS has a large list of the most commonly measured environmental parameters and a comprehensive list of units. Both SI and English units are available and data can be converted from one to the other without loss of precision. The system is also extensible, meaning additional parameters and units can be added.   All parameters in AQUARIUS must have defined units to facilitate conversion into other parameters through integration, differentiation, or rating curve transformations. Many of the computed parameters from time series datasets such as total runoff and maximum rainfall intensity require special treatment of data interpolation between recorded values.

AQUARIUS supports the standard array of interpolation types (sometimes known as “data types”) such as instantaneous values, total in preceding interval, discrete value, directional values etc… This allows AQUARIUS to compute values such as total daily discharge even when data is sparse or needs to be extrapolated to a boundary.

Finally, AQUARIUS tracks the time zones of all time tags in datasets. This is an important facility for flood forecasting and also for managing time tags from telemetry feeds which may be decoded in UTC versus direct logger file downloads which are often in Local Standard Time. Of course, it is also very important for managing networks of stations that span time zones.

Visualization of Vertical Profile Datasets

One of the more challenging types of data to analyze is data from vertical profiles or soundings of a water body. These datasets are often collected manually by performing casts with a sensor sonde, or they can be collected by automated sounding buoy platforms such as the YSI Vertical Profiler.

Analysis of this type of data can answer important questions such as the depth and magnitude of thermoclines, or the precise time at which water column turnover occurred.  However extracting this information from the large 3D datasets can be extremely difficult without the proper tools.  The AQUARIUS Workstation Profiling Toolbox easily handles this type of data allowing users to focus on interpretation and analysis instead of data formatting and gridding.

Plotting Meteorological Data

Certain interpolation types require special treatment when it comes to data visualization.  Examples of these types of data are rainfall accumulations and intensities, as well as directional parameters such as wind.  An example of how AQUARIUS helps to visualize these types of data is the visualization of wind direction and speed data in a wind rose chart.

River and Reservoir Water Volume Accounting

Accounting for water volume as it moves through a hydrologic system is imperative for the optimal operation of hydropower, navigation, agriculture, water allocation and other water management systems.  Setting up water volume accounting calculations is an extremely difficult task.  Even if all the datasets are available they are seldom at the same sampling frequency or exact time stamp. Datasets may have gaps, and visualization of the calculation and the results can be difficult.  The AQUARIUS Workstation’s Whiteboard environment is the answer for performing these water volume accounting calculations.

The visual layout environment of the Whiteboard allows a user to wire together the accounting calculations as a schematic of the actual physical system.  The AQUARIUS Math toolboxes take care of the details of time series to time series mathematics such as interpolation to a common time step using the correct interpolation rules.  Results can be visualized at any step, and final numbers can either be saved back to the database or simply used as a temporary series for reporting purposes. AQUARIUS Whiteboard processes that calculate reservoir inflow minus outflow vs. difference in calculated contents can be saved as processes and re-run whenever needed (shown right).