The use of Florida Atlantic University's the Ocean Explorer, asmall autonomous underwater vehicle, as a mobile platform foroceanographic measurements is described. The OEX is a 2.4 m longversatile, Gertler body which can perform pre-programmed underwatermissions to a depth of 300 m. At a speed of 1-2 m/s, it can performmissions over a period of several hours, collecting in-situoceanographic data and storing it on an on-board data-logger. Threemissions are described, two in shallow waters off the coast of SouthFlorida during December, 1997, and one in the Gulf Stream during July1997 at depths of up to 130 m. During the missions, the AUV was equippedwith a 1200 kHz broad band ADCP, a CTD package and, on the Gulf Streammission, a small-scale turbulence measurement package. The vehicle mayalso carry a side-scan sonar or other instruments for subsidiarymeasurements. The versatility of the AUV allows measurement ofoceanographic data over a substantial region, the motion of the platformbeing largely decoupled from that of the sea surface. In the missions ofDec. 5 and 11, 1997, “lawn-mower pattern” AUV surveys wereconducted over 1 km2 regions on the east coast of Florida, north of FortLauderdale, at a depths of 7 m and 3 m respectively in a water columnwhere depth ranged from 10-32 m. During Dec. 5, the region was subjectedto a cold front from the northwest. Local wind measurements showpresence of up to 10 m/s winds at temperatures of up to 10-150 C belownormal for the, time of the year. Measurements are compared with thoseof a fixed ADCP. In the Gulf Stream missions, significant shear layerswere encountered. Bathymetry, current, CTD and small-scale turbulencemeasurements obtained during the missions are presented and the problemsassociated with making such measurements and choosing samplingstrategies is discussed
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