1 Conceptual Models (CMs): Stau (Alps) Lee waves Snow How to use MSG satellite images similarities to and improvements over MTP Contact person: Veronika Zwatz-Meise Version July 2004

2 CMs: Stau (Alps) Lee waves Snow MTP channels in comparison with the corresponding MSG channels CM Stau: IR image + relevant NWP parameters MSG additional channels + Channel combinations

3 MTP: VIS Stau Lee waves Snow As the image time between MTP and MSG differs, a shift between the cloud systems can be noticed in the two images

4 MSG: CH01 Stau Lee waves Snow Looks relatively similar; but: somewhat coarser space resolution best seen at lee waves

5 MSG: CH02 Stau Lee waves Snow Looks relatively similar; but: somewhat coarse space resolution best seen at lee waves ; much better recognition of vegetation as in Ch01

6 MTP: IR Stau Lee waves Snow

7 MSG: CH09 Stau Lee waves Snow Sharper contours through improved space resolution; especially well seen at lee waves; lee waves are better discernable in IR; relative high, cold cloud tops ?

8 MTP: IR+VIS Stau Lee waves Snow

9 MSG: 129 Stau Lee waves Snow Sharper contours and more detailed grey-shades through improved space resolution in IR and additional information from 2 different VIS channels; less resolution for lee waves from the VIS channels

10 MTP: WV Drying by sinking air at lee side

11 MSG: CH05 Drying by sinking air at lee side; no (nearly no) lee cloud visible; no radiation from farther below

12 MSG: CH06 Lee waves In CH06 are lee waves visible: radiation from lower levels reach the satellite

13 CMs: Stau Lee waves Snow MTP channels in comparison with the corresponding MSG channels CM Stau: IR image + relevant NWP parameters MSG additional channels + Channel combinations

14 Stau Lee waves Snow Surface high pressure approaches the Alps from SW; Stau as well as lee waves appear in N stream

15 Stau Lee waves Snow Upper level trough; Stau as well as lee waves appear in NW stream

16 Stau Lee waves Snow Wind vectors at 850 hpa Stau within W stream at 850; lee within NW stream at 850

17 Stau Lee waves Snow Wind vectors at 700 hpa Stau within NW stream at 700; lee within NW stream at 700; wind turns to more NW directions

18 Stau Lee waves Snow Wind vectors at 500 hpa Stau within NW stream at 500; lee within NW stream at 500; wind speed is strong in all three levels

19 Stau Lee waves Snow Thickness + TFP Stau and lee waves within thickness trough

20 CM: Stau Lee waves Snow MTP channels in comparison with the corresponding MSG channels CM Stau: IR image + relevant NWP parameters MSG additional channels + Channel combinations

21 CH01 Stau Lee waves Snow Stau cloud, lee waves and snow are white; lee waves are partly only grey (thin)

22 CH02 Stau Lee waves Snow Stau cloud, lee waves and snow are white; lee waves are partly only grey (thin); vegetation structure and lakes clearly visible

23 CH03 Stau Lee waves Snow Stau cloud and lee waves are white to light grey; snow is darkgrey to black; lakes are black

24 CH04 Stau Lee waves Snow Interesting is black snow structure; sharp edge for Stau cloud at Alps; black area to the S cold cloud and/or (?) snow

25 RGB134 Stau Lee waves Snow Interesting is snow structure; brown at W-Alps where there is snow and small stripe S of Alps in Austria; are both snow ? sharp edge for Stau cloud at Alps much better visible as from single channels;

26 RGB139 Stau Lee waves Snow Interesting is snow structure; pink at W-Alps where there is snow; small stripe S of Alps in Austria has other colour seems to be high cloud; sharp edge for Stau cloud at Alps much better visible as from single channels;

27 RGB149 Stau Lee waves Snow Interesting is snow structure; pink at W-Alps where there is snow; small stripe S of Alps in Austria has other colour seems to be high cloud; sharp edge for Stau cloud at Alps much better visible as from single channels;

28 RGB321 Stau Lee waves Snow Cyan appears at the snow and typically superimposed in the small stripe S of the Alps in Austria; Represents Ice cloud and snow