Supplement 1.2: Remote Sensing Instruments Used in Marine Pollution Monitoring



Platform /
Sensor
Abbr. Wavelength range in which the sensor is operating Method What does it ‘see’? Limitations Application
   Satellite
Synthetic Aperture Radar SAR Microwaves:
1 mm - 1 m
active reflectance properties of the sea surface at microwave frequencies not applicable in heavy rain conditions and in wind <2 Bft and >6 Bft presence and extent of slicks at the sea surface
   Aircraft
Side-Looking Airborne Radar SLAR Microwaves:
1 mm - 1 m
active reflectance properties of the sea surface at microwave frequencies not applicable in heavy rain conditions and in wind <2 Bft and >6 Bft long-range detection of slicks at the sea surface
Laser Fluorosensor LFS / LIDAR UV-VIS:
300-700 nm
active fluorescence spectra specific to oil class, water Raman scatter dependent on film thickness not applicable with clouds between aircraft and sea surface advanced analysis of pollutants, e.g. identification of oil species and film thickness in the range 0.1 - 10 μm
Downward-looking Thermal Infrared IR Scanner Infrared (IR):
8 - 14 μm
passive brightness temperature in the thermal infrared not applicable with clouds between aircraft and sea surface temperature differences on the sea surface; e.g. relative film thickness of oil of approx. 10 - 100 μm
Downward-looking Ultraviolet UV Scanner Ultraviolet (UV):
280 - 400 nm
passive reflected UV solar radiation in daylight only, not applicable with clouds between aircraft and sea surface e.g. relative film thickness of oil of up to 10 μm
Forward-looking Infrared FLIR Infrared (IR):
8 - 14 μm
passive brightness temperature in the thermal infrared not applicable with clouds between aircraft and sea surface temperature differences on the sea surface
Microwave Radiometer MWR Microwaves:
1 mm - 1 m
passive brightness temperature at microwave wavelengths not applicable in heavy rain conditions analysis of oil film thickness >100 μm
Multispectral Imager VIS/NIR Scanner VIS-NIR:
400 - 1100 nm
passive reflectance of daylight at various visible and near-infrared wavelengths not applicable with clouds between aircraft and sea surface presence, extent and relative thickness of oil spills in the range 0.1 - 100 μm




Wavelengths and frequencies of electromagnetic waves on logarithmic scales, and spectral range of remote sensing instruments used for marine pollution detection and analysis. Passive instruments detect signals which are naturally available, e.g., sunlight reflected or thermal radiation emitted from a target. Active instruments provide their own source of radiation for target illumination and signal detection.

See module Understanding Spectra from the Earth for more details on electromagnetic waves.