Spain-Morocco-Strait of Gibraltar

Internal waves (wavelength about 2 km) which seem to move from the
Atlantic ocean to the Mediterranean Sea, at the east of Gibraltar and Ceuta

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Internal waves are usually created by the presence of two different layers of water combined with a certain configuration of relief and current. In the case of the Strait of Gibraltar, the two layers correspond to different salinities, whereas the current is caused by the tide passing through the Strait. As this current meets the ascending ocean bottom in the Strait, the internal waves are generated, reaching the surface some kilometres behind the Strait. They are not directly visible to the observer, but produce a perturbation at the surface that appears as strips of rough and calm water. ERS-1 therefore gives scientists the opportunity to observe and map such phenomena.

• Artificially coloured image
• Acquired at the Fucino ground station on 7 January 1992
• Area covered is 90 km x 100 km.

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry