by George Lammons
Ocean Forecasting Emerges as a New Discipline with the Emphasis on ASW New developments in ocean forecasting at the Naval Oceanographic Office (NAVOCEANO) are revolutionizing the way warfighters look at oceanography and how it enhances their ability to conduct Anti-Submarine Warfare (ASW). The newly-established Ocean Forecast Group now forecasts ocean conditions in much the same way meteorologists forecast atmospheric conditions – a discipline the team developed from scratch. “We have built a capability from ground zero — developing procedures, tools and methods based on our experience probing the ocean and collecting data from it,” said Capt. Jim Berdeguez, NAVOCEANO commanding officer. The culmination of this data yields an ocean forecast that ultimately provides commanders with enhanced means to make tactical decisions. As varying ocean conditions affect the way acoustic sensors perform, the forecasters predict those conditions and describe the impact on acoustics in a particular setting. “Ocean forecasters provide integral support to ASW by taking model output and turning it into tactically relevant information that helps warfighters decide where and how to best use their sensors,” said Cmdr. Tony Miller, commanding officer of the Naval Oceanography Anti-Submarine Warfare Center at NAVOCEANO.
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Probability of Detection averaged over 30 kyds vs. a threat at 150 ft
Probability of detecting a target somewhere between the sensor and a range of 30 kyds distant when the target is in the surface duct (maximum depth ~400 ft).
Probability of Detection averaged over 20 kyds vs. a threat at 510 ft
Probability of detecting a threat somewhere between the sensor and a range of 20 kyds distant when the target is at an operating depth below the surface duct.
NOTE: “Good” performance against a deep target occurs on the deep-duct side of the poor performance shallow-duct areas (Gridlines included for reference purposes only).
Graphic representations provided by the Naval Meteorology and Oceanography Command
Full-field plots of duct leakage leading to below-duct detection potential. Areas where the duct shallows are directly linked to areas where there is significant energy below duct due to duct leakage.
The Ocean Forecast Group was established to enhance the growing ASW activities of the Naval Meteorology and Oceanography Command (NMOC). The Navy uses a variety of tools to discern acoustic performance: ocean data from several sources, numerical ocean models, acoustic models — and now ocean forecasters, who provide additional analysis as weather forecasters provide analysis to weather models and atmospheric data. By analyzing how ocean variables affect sound speed and sonar performance, the
ocean forecasters verify where data and the resulting models work, and how to weigh the data in a particular operational area. “They are the ones who are analyzing and adding real value to the model output,” said Berdeguez. Jay Wallmark, Ocean Forecast Team Leader, added: “We are able to filter out all the irrelevant data, based on the oceanography of a particular area and the way sensors work.” NAVOCEANO has long used models and data graphics that show general ocean
