7.3 General Aids to Fishing OperationsSatellites can assist the fishing industry in many ways other than the locating of fish per se. Most of these aids are also of assistance to mariners other than fishermen. The types of assistance that satellites can offer include the following: i) search and rescue operations: The satellite NOAA-8 carries a special sensor, SARSAT (Search and Rescue Satellite Tracking), which detects the distress signals emitted by vessels in difficulty. The recorded signal is used to locate the position of the vessel. Sensors carried on board the Russian satellite series COSPAS-1, 2 and 3, launched respectively in 1982, 1983 and 1984, fulfill a similar function to SARSAT; ii) weather reports: Environmental satellites such as NOAA, GOES or METEOSAT can provide weather information over a wide area at a given time (refer to Figure 7.6). This may assist fishermen to plan their fishing operations. In higher latitudes, ice and icebergs are major hazards; environmental satellites can assist in identifying ice and spotting icebergs; iii) bathymetry: Remote sensing using passive or active visible sensors may be used for bathymetric measurements. With the exception of acoustic methods (sonar), airborne sensors provide the most accurate bathymetric measurements. In addition, active sensors such as bathymetric lidar are more reliable than the passive devices.
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