Remote sensing is a rapidly evolving technology which uses aerial photography and satellite imagery to provide information on the distribution of a variety of physical and biological parameters in the ocean.
The ocean is a complex and dynamic system which displays variability over a range of time and space scales. Marine remote sensing, or satellite oceanography, provides data that are an invaluable complement to information collected from ships, such as information on current patterns and ocean surface characteristics, including surface temperature and amounts of phytoplankton. It can provide synoptic coverage which cannot be achieved using other methods.
Many oceanic parameters can be measured by remotely-based sensors. They include sea-surface temperature, sea-ice distribution, turbidity and ocean colour, which may be related to biological productivity. Active sensors such as the radar altimeter and microwave scatterometer on board the European Space Agency Satellite ERS-1 can provide information on ocean currents, ocean fronts, eddy structures and wave statistics.
A number of new satellite based sensors are planned over the next decade. They include US National Aeronautics and Space Administration (NASA) instruments such as the Sea-viewing Wide-Field-of-View Sensor (SeaWIFS) and the Moderate Resolution Imaging Spectrometer (MODIS). Both the European Space Agency and the Japanese National Space Development Space Agency also plan ocean colour missions during the 1990s. The continuing international commitment to the collection of remote sensed data should ensure growing opportunities for careers in this field.
Both physical and biological oceanographers utilise remotely sensed data, and it is these groups that provide most of the demand for marine remote-sensing specialists. Thus, most job opportunities in this field are with universities and commonwealth agencies, for example CSIRO, the Australian Institute of Marine Sciences, the Australian Antarctic Division, and the Australian Centre for Remote Sensing. Increasingly however, coastal engineers and other professionals, particularly those concerned with monitoring and managing coastal environments, are making use of remote sensing to detect changes in shoreline morphology, the extent of shallow reef systems, or the extent and distribution of coastal vegetation such as mangroves and seagrasses.
Photo: A plume from the Fitzroy River, Queensland, as captured by the LANDSAT Multispectral Scanner.