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Emma Stibbon ‘Sonar and 3D images of the seabed’ Blog 3 From HMS Protector
The ship has an array of monitoring devices onboard, primarily concerned with hydrography and navigation. ‘Sonar data collection on the Bridge’
I am learning about the different surveying devices that are used to map the seabed. The ship is fitted with multiple and single beam sonar geodetics that emit beams of sound energy off the seabed. The ship tracks the mapping area (a bit like mowing a lawn), producing lines of sonar data that is then sent to the Chart Room onboard. Here it is expertly ‘cleaned’ – the surveyors will use their skill to remove any excess noise – and digitally convert the data into positions and depth. The digital programme from the data produces astonishing 3D images of the seabed.
The Gunnel seabed, image courtesy of Chart Room HMS Protector
This data is sent to the Admiralty UK Hydrographic Office in Taunton where it will be used to make new navigational charts of the Peninsula area. Antarctica is poorly charted due to it’s inaccessibility. Much of the coastline of the Peninsula has not been surveyed for over two centuries. This would have been done by whaling ships, using a lead-line and a sextant, and the depth soundings are sporadic. It is impressive to consider that the ship is contributing to new chart data that will aid shipping in the area into the future.