1. 1 Conceptual Models (CMs): Cold Air Cloudiness (CAC), Enhanced Cumulus (EC ) and Comma How to use MSG satellite images similarities to and improvements over MTP Contact person: Veronika Zwatz-Meise zwatz-meise@zamg.ac.at Version 1.0. 13 July 2004

2. 2 CMs: CAC, EC and Comma (Cold Air Cloudiness and Enhanced Cumulus) MTP channels in comparison with the corresponding MSG channels CMs: CAC+EC: IR image + relevant NWP parameters MSG additional channels + Channel combinations

3. 3 MTP: ir CAC EC Co As the image time between MTP and MSG differs, a shift between the cloud systems can be noticed in the two images

4. 4 MSG: Ch09 Sharper contours through improved space resolution CAC EC Co

5. 5 MSG: Ch10 Visual inspection shows only very slight changes between Ch09 and Ch10; quantitative evaluation necessary CAC EC Co

6. 6 MTP: vis CAC EC Co

7. 7 Looks relatively similar; but: somewhat coarser space resolution MSG: Ch01 Grey clouds represent transperent clouds CAC EC Co

8. 8 MSG: Ch02 Compared to Ch01: no strong differences in the cloud features over the ocean; but: much better land recognition Visibility of transperent clouds worse thanin Ch01 CAC EC Co

9. 9 MTP:VIS(2x)+IR Blue: high cloud is very dominant CAC EC Co

10. 10 MSG:129 Sharper contours and more detailed grey-shades through improved space resolution in IR and additional information from 2 different VIS channels Dark blue: High cloud light blue: thick cells yellow: less thick cloud cells CAC EC Co

11. 11 CMs: CAC, EC and Comma (Cold Air Cloudiness and Enhanced Cumulus) MTP channels in comparison with the corresponding MSG channels CM CAC+EC: IR image + relevant NWP parameters MSG additional channels + Channel combinations

12. 12 H500 CAC, EC and Comma within huge upper level trough

13. 13 Thickness CAC, EC and Comma within huge thickness trough

14. 14 Thickness (green) + TA (red) CAC, EC and Comma within huge thickness trough and mainly under CA

15. 15 Showalter index EC: unstable (Show < 3) Comma: Show > 5; much less unstable

16. 16 PVA at 500 hPa EC and Comma: both are accompanied by distinct PVA max

17. 17 Height and PVA at 500 EC and Comma: both PVA max are connected to upper level troughs

18. 18 Isotachs 300 EC and Comma: both are on cyclonic side of jet streaks but: Comma is in left exit region

19. 19 Isotachs and PVA 300 EC: no PVA max at 300 Comma: distinct PVA max in left exit region of the jet streak

20. 20 CMs: CAC, EC and Comma (Cold Air Cloudiness and Enhanced Cumulus) MTP channels in comparison with the corresponding MSG channels CM CAC+EC: IR image + relevant NWP parameters MSG additional channels + Channel combinations

21. 21 EC Co CAC MSG:129 For reasons of comparison with analoge RGBs fron NOAA the IR ch09 is inverted CAC: yellow: low cloud tops EC: yellow + blue: vertically extended cells Co: blue: mainly cold cloud tops

22. 22 EC Co CAC MSG: Ch03 CAC: white: water cloud EC: white + dark grey: water cloud + ice cloud superimposed Co: dark grey: mainly cold cloud tops

23. 23 EC Co CAC MSG:321 Grey shades: from Vis channels Cyan: represents the ice clouds from Ch03

24. 24 EC Co CAC MSG:139: The IR ch09 is inverted CAC: yellow: low/warm cloud tops EC: magenta + blue: vertically extended cells Co: blue: mainly cold cloud tops some magenta spots visible

25. 25 EC Co CAC MSG:139: The IR ch09 is not inverted but used as original radiation Brown: thin cold ice cloud Brown-red:thick, multilayered cloud Yellow: thick water cloud

26. 26 EC Co CAC MSG:134 CAC: yellow: low/warm cloud tops EC: yellow + brown: vertically extended cells Co: brown: mainly cold cloud tops some yellow spots visible