Aeolian Islands Italy
406 of 1114

Aeolian Islands, Italy

January 20, 2006
This image shows an area of 70 Km swath width centered over the Aeolian Islands.

On the lower part of the image the north coast of Sicily is visible with, in the center and upper part of the image, five of the seven Aeolian Islands (respectively from bottom to top, Vulcano, Lipari, Salina, Panarea and in the upper left part of the image Stromboli).

The particular interest of this image is to highlight the footprints of the wind on the sea surface. For example, between Stromboli and Panarea, a sudden variation in tone, related to specific vertical clouds, reveals a distinct change in surface wind speed. The same structure is visible on the left hand side of Stromboli with a particular effect called splash down (white patch). This effect consists of a very strong rain in a precise area that increases the sea surface roughness, producing stronger backscatter energy towards the antenna. The wind speed direction is determined by the dark area located on the right hand side of the islands (dark line on the right side of Stromboli reveals precisely the lower left to upper right wind direction). The relief creates wind protected areas with low sea surface roughness. As a result, these smooth sea surfaces reflect specularly the signal away to the antenna producing the dark areas.

Technical Information:
  • Satellite: Envisat
  • Instrument: ASAR
  • Acquisition: 23-Jan-2003
  • Orbit nr: 04699
  • Center coordinates: lat. 38.37, lon. 15.25

comments powered by Disqus