OAD products are delivered with all of the required data sets to facilitate sonar performance prediction on a Global basis. Some of these data sets can be augmented with the users’ own data for specific situations. The embedded data is obtained from established and reputable 3rd party organisations and then processed and enhanced by OAD for use by WADER and HARCAM.

Source: The US Navy Marine Climatic Atlas of the World (USMCAW)

Spatial resolution: 1 degree

Temporal resolution: 1 month

Notes: The source data was processed by OAD to produce a set of simple charts. These charts can be used to prepare briefing notes and also provide sea state data for the propagation loss models.

• Wave Height
• Gale Probability
• Surface Wind Speed
• Surface Air Pressure
• Surface Air Temperature
• Surface Dew Point
• Surface Air Temperature minus Surface Dew Point
• Surface Sea Temperature minus Surface Dew Point

Source: OAD (from WOA and GEBCO)

Spatial resolution: 0.25 degrees  

Temporal resolution: 1 month

Notes:  The charts are –

• Sea Surface Temperature
• Sea Surface Salinity
• Sonic Layer Depth
• Secondary Layer Base
• Shallowest Channel
• Depth Excess
• Range to First Convergence Zone

We are rather proud of the Range to First Convergence Zone (CZ) charts which show where CZ conditions can be found and what the expected ranges will be. The charts are constructed using water column and bathymetry data together with the HODGSON propagation loss model (chart example: January).

Source: World Ocean Atlas 2018 Beta / 2013 V2*

Spatial resolution: 0.25 degree

Temporal resolution: 1 month

Notes: OAD spatially enhances the data to ensure that all profiles extend to the seabed and all grid squares are supplied with a profile.

Both 1 and 0.25 degree datasets are provided for reference.

Both 1 and 0.25 degree data available for areas with space data coverage at high resolution.

This climatological data is supported by Expendable Bathythermograph (XBT) from the WOA. The WOA provides approximately 500,000 measured XBT taken at random times and with random distribution.

Source: GEBCO V3*

Spatial resolution: 0.5 arc minutes, subsampled to 1 and 2 arc mins

Temporal resolution: N/A

Notes: OAD endeavour to supply the highest quality data available. This was DBDB5 (5 min resolution) when the system was produced in 1991 (issued on 28 floppy discs). We have since progressed through ETOPO5, DBDBV and ETOPO2, all of which provided increased spatial resolution.

ESRI Raster Format Reader: WADER V8.2 also allows users to upload their own high-resolution bathymetry data in ESRI Raster Format (ASCII) where available and appropriate.  Data resolution can be as high as 0.5m.

Source: World Vector Shoreline Dataset, NGDC, Boulder, Colorado (WVS)

Spatial resolution: 1:100000

Temporal resolution: N/A

Notes: Standard WADER charts are drawn using bathymetry data. This is suitable for the open ocean but provides limited coastline definition when ‘zoomed in’ (especially around island areas). WVS data provides an effective way of drawing high definition coastlines.

Source: HFEVA Stennis Space Centre*

Spatial Resolution: 6 arc seconds (specific areas), 5 arc minutes (near Global)

Temporal Resolution: N/A

Notes: HFEVA is used in its original format for higher frequencies.  The same dataset has been transposed using recognised algorithms by OAD to provide data suitable for both mid and low frequencies.  The data is available to view graphically (as chart overlays and as seabed reflection loss curves) and is used by the program for calculations.

Source: OAD

Notes: The majority of military sonar parameters are classified. Therefore OAD has created a set of Sonar Parameters for Unclassified Training (SPUTs) which are designed to emulate the behaviour of real sonars for training and planning purposes. For operational use, WADER will require the actual parameters of any relevant sonars to be uploaded by the user.

Read more about WADER and HARCAM here.

* Dataset used for WADER.  HARCAM currently uses an older version as a result of benchmarking.  Contact OAD for further details.