Example of Fog over Northern Europe

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Example of Fog over Northern Europe

• 24 Feb 2004 a winter case, fog over cold snow
  surface
• 29 May 2004 fog over sea drifting ashore
• Pirkko Pylkkö
• Finnish Meteorological Institute
• (See alsowww.knmi.nl/satrep Satrep Manual)

1/30.6.2004
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Winter case 24 Feb 2004

• Fog over snow surface
• Fog top warmer than surrounding snow surface gt
  in IR channels fog darker than surface
• In the winter mostly nighttime or twilight
  conditions
• 10.8 and 12µm channels better than 3.9µm for fog
  above cold snow at night
• Next pages First AVHRR 10.8 and 3.8µm images and
  then same channels from SEVIRI (date 24 Feb 2004
  0130UTC)

2/30.6.2004
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AVHRR 10.8µm
Fog
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(No Transcript)
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SEVIRI 10.8 µm
Fog
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SEVIRI 3.9µm
Fog
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Fog over sea 29 May 2004

• Daytime fog can be seen also in visible channels
  very well
• SEVIRI HRV can be of assistance also in the north
• Animating SEVIRI images makes fog more easy to
  recognize
• Following pages SEVIRI 1.6, 0.8 and 0.6 µm

AVHRR channels 0.6, 0.8, 10.8µm
7/30.6.2004
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1345UTC
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1400UTC
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1430UTC
11
SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1500UTC
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1515UTC
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1530UTC
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1545UTC
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SEVIRI 1.6, 0.8, 0.6 µm combination 29 May 2004
1600UTC