APL-SASEA-An Oceanographic Data Analysis System

Reference#: P01912

Real time oceanographic information from multiple sensors is critical for current maritime activities and future exploration activities. Researchers at the Johns Hopkins Applied Physics Laboratory (JHU/APL) have developed the System for At-Sea Environmental Analysis to accomplish this task and present the information to operators and scientists in meaningful graphical displays.

Current software covers selected oceanographic parameters and displays them in a post-test processing mode through plots and data tables. No available system integrates all the parameters into a near real time graphical display. SASEA processes data from the following sources:

* Conductivity-Temperature-Depth (CTD) sensors

* eXpendable BathyThermograph (XBT)

* Airborne eXpendable BathyThermograph (AXBT)

* eXpendable Conductivity-Temperature Depth (XCTD) sensors

* eXpendable Sound Velocimeters (XSV)

* Historical data archives (MOODS, GDEM)

The software for this invention has a modular design with core capabilities that include profile editing, analysis, database and visualization of oceanographic data.

The Profile Editing module allows a user to apply advanced processing techniques, such as data smoothing and elimination of data spiked or redundant data values. These tools are primarily graphically oriented, as the user operates on a plot of the profiles. A unique on-screen validation feature allows for the user to compare results with the original raw data.

The Analysis module includes algorithms that perform a variety of functions, such as calculating profile density, Brunt-Vaisala frequency, and creating surface-to-bottom speed profiles. A unique feature of this module is the profile merge which generates surface-to-bottom sound speed profiles from temperature measurements. Measured temperature profiles are merged with CTD or historic temperature-salinity data to create the surface-to-bottom temperature-salinity profiles. Bathymetric databases are accessed to provide proper cut-off depths.

The Database Tools module includes options for creating, updating, and sorting data from a profile database, and also provides methods to extract data from existing profile databases. Those tools include profile extraction, profile cut-off, profile information, profile data inventory, and update database.

The graphics module includes interactive profile plotting, contouring, and mapping tools with built-in extraction routines.

The modular approach to SASEA will allow continued development of new applications, such as extensions to optical and current data formats with enhanced calculation and data visualization capabilities. SASEA operates on any platform supported by MATLAB.

Mr. E. Chalfin
Phone: (443) 778-7473

Additional References:

APL-SASEA Specification Sheet