page_title: Prince Edward Islands
section_title: Amateur radio
hierarchical_section_title: Prince Edward Islands / Amateur radio
caption_attribution_description: English: Early November 2015 brought cloudy skies and intriguing patterns over the Prince Edward Islands in the South Indian Ocean. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this scene on November 5. The Prince Edward Islands have been outlined in black so they can be viewed under the heavy cloud cover. The wind is blowing from the southwest to the northeast. On the windward side of the island the clouds are undisturbed. On the leeward side, however, the turbulent air has formed a pattern known as ship-wave-shaped clouds. The pattern gets its name because the cloud pattern resembles the waves created by moving objects, like a ship or even a duck. In this case, the object (Prince Edwards Islands) were stationary, and it was the wind moving past. While the mechanisms are different, the waves generated in each fashion have similar forms. In this case, the moving air swept around the tall peaks of the mountains on the Prince Edward Islands and created turbulent air on the leeward side. The flow of the turbulence is in a spreading V shape behind the point. At the same time, the forward motion occurs in waves, with peaks and trough as the turbulent air flows further away from the point source which caused it. When atmospheric conditions are right, cloud form on the cool peaks of a wave of air but cannot form on the low trough. The result, as seen in this image, are areas of clear and cloud-filled stripes perpendicular to the forward motion of the turbulence.
context_page_description: The Prince Edward Islands are two small islands in the subantarctic Indian Ocean that are part of South Africa. The islands are named Marion Island and Prince Edward Island.
  The islands in the group have been declared Special Nature Reserves under the South African Environmental Management: Protected Areas Act, No. 57 of 2003, and activities on the islands are therefore restricted to research and conservation management. Further protection was granted when the area was declared a marine protected area in 2013. The only human inhabitants of the islands are the staff of a meteorological and biological research station run by the South African National Antarctic Programme on Marion Island.
context_section_description: As of 2014, Marion Island, prefix ZS8, was the third most wanted DXCC "entity" by the amateur radio community. By the end of 2014, it had dropped to 27th, after simultaneous activity by three licencees in the 2013/2014 team. However, their activity was mainly on voice. On Morse telegraphy, the Islands remain the second most wanted entity after North Korea, while on data they are sixth out of 340.
caption: Cloud patterns over the Prince Edward Islands
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