1 Conceptual Models (CMs): Cold fronts (CF), Ana- and Katatype How to use MSG satellite images similarities to and improvements over MTP Contact person: Veronika Zwatz-Meise Version July 2004

2 CMs: Cold Fronts (Ana-and Katatype) MTP channels in comparison with the corresponding MSG channels CM Cold Fronts: IR image + relevant NWP parameters MSG additional channels + Channel combinations (WV and WV difference images)

3 CM: Cold Fronts Typical Anacoldfront

4 MTP: ir CF As the image time between MTP and MSG differs, a shift between the cloud systems can be noticed in the two images

5 MSG: Ch09 Sharper contours through improved space resolution CF Grey: warm cloud tops White: cold cloud tops

6 MSG: Ch10 Visual inspection shows only very slight changes between Ch09 and Ch10; quantitative evaluation necessary CF

7 MTP: vis CF

8 Looks relatively similar; but: somewhat coarser space resolution MSG: Ch01 White: high albedo CF Grey: transparent

9 MSG: Ch02 Compared to Ch01: no strong differences in the cloud features over the ocean; but: much better land recognition CF

10 MTP:VIS(2x)+IR CF

11 MSG:129 Sharper contours and more detailed grey-shades through improved space resolution in IR and additional information from 2 different VIS channels CF White/grey/blue: multilevel blue: high

12 CM: Cold Fronts Typical Katacoldfront

13 MTP: ir CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; in IR detectable only from general structure

14 MSG: Ch09 Sharper contours through improved space resolution CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; in IR detectable only from general structure

15 MTP: vis CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; in vis differentiation between thick and transparent cloud parts possible

16 MSG: Ch01 Looks relatively similar; but: somewhat coarser space resolution CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; in vis differentiation between thick and transparent cloud parts possible

17 MSG: Ch02 Compared to Ch01: no strong differences in the cloud features over the ocean; but: much better land recognition CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; in vis differentiation between thick and transparent cloud parts possible

18 MTP:VIS(2x)+IR CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; blue: high cloud on anticyclonic jet side grey: thick cloud parts

19 MSG:129 Sharper contours and more detailed grey-shades through improved space resolution in IR and additional information from 2 different VIS channels CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; blue: high cloud on anticyclonic jet side grey: thick cloud parts line of lower cloud cells discernable

20 MTP: wv CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; jet axis through dark stripe well recognisable

21 MSG: Ch05 CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; jet axis through dark stripe well recognisable

22 MSG: Ch06 CF Typical intensification of front cloud on cyclonic side of a crossing jet streak; Ch06: Signals from much lower down in tropopshere; black stripe crossing frontal cloud band less good but still recognisable

23 CMs: Coldfronts (Ana- and Katatype) MTP channels in comparison with the corresponding MSG channels CM Coldfronts: IR image + relevant NWP parameters MSG additional channels + Channel combinations (WV and WV difference images)

24 CM: Cold Fronts Typical Anacoldfront

25 Thickness (green)+ TFP (blue) High gradient of thickness at rearward edge of frontal cloud band; TFP close to the leading edge of the frontal cloud band

26 Thickness (green) + TA (red) Zeroline of TA close to rearward edge of frontal cloud band; CA at 700 within biggest part of frontal cloud CA

27 Isotachs 300 Jetaxis and jet streak along rearward side of frontal cloud band

28 MSG: Ch05 zeroline of shear vort 300 (yellow) Zeroline of shear vorticity 300 (jetaxis) fits to transition from wet to dry

29 Zeroline of shear vorticity 300 (jetaxis) fits to transition from wet to dry; no tilt between Ch05 and 06 recognisable MSG: Ch06 zeroline of shear vort 300 (yellow)

30 MSG:139 zeroline of shear vort. 300 (black) Zeroline of shear vorticity 300 (jetaxis) fits to the margenta fibre at the rear of the cloud band; high cold tops consisting of ice

31 CM: Cold Fronts Typical Katacoldfront

32 Thickness (green)+ TFP (blue) High thickness gradient and TFP close to rear side of frontal cloud band as well as in the intensification area;

33 TA (red) Main part of the frontal cloud band is under WA at 700

34 Isotachs (yellow) + PVA (red) at 300 A jet streak crosses the front at the N-S oriented part; the intensification area is under strong PVA in the left exit region of the jet streak PVA max

35 MSG: Ch09 zeroline of shear vort 300 (black) The jet axis (zeroline of shear vort. At 300) crosses the cloud band at the N-S oriented part

36 MSG: Ch05 zeroline of shear vort 300 (black) The jet axis (zeroline of shear vort. at 300) is close to the dark stripe in WV

37 MSG: Ch06 zeroline of shear vort 300 (black) The jet axis (zeroline of shear vort. at 300) is close to the dark stripe in WV; but: it is drier than in the upper WV channel; some tilt between Ch05 and Ch06

38 CMs: Coldfronts (Ana- and Katatype) MTP channels in comparison with the corresponding MSG channels CM Cold Fronts: IR image + relevant NWP parameters MSG additional channels + Channel combinations (WV and WV difference images)

39 CM: Cold Fronts Typical Anacoldfront

40 MSG:129 Yellow/grey/blue: multilayered; transparent cold cloud line at the rearward edge CF

41 MSG: Ch03 CF Ice clouds are superimposed on water clouds; line of ice clouds along rearward edge of frontal cloud band

42 MSG:321 Grey shades: from Vis channels Cyan: represents the ice clouds from Ch03: line of ice clouds along rearward edge of frontal cloud band CF

43 MSG: Ch04 Black: cold cloud tops CF

44 MSG:139 Blue: cold transparent cloud Magenta: ice cloud line of ice cloud along rearward edeg CF

45 MSG:134 Brown/orange: cold cloud top; ice cloud CF

46 CM: Cold Fronts Typical Katacoldfront

47 MSG:129 Yellow/grey/blue: multilayered; transparent cold cloud; thick cloud in the intesification area

48 MSG: Ch03 Ice clouds are superimposed on water clouds; intensification area consists of ice and water cloud

49 MSG:321 Grey shades: from Vis channels Cyan: represents the ice clouds from Ch03: intensification area shows ice on top of water cloud

50 MSG: Ch04 Black: cold cloud tops

51 MSG:139 Blue: cold transparent cloud Magenta: ice cloud intensification area is magenta

52 MSG:134 Brown/orange: cold cloud top; ice cloud; intensification area is brown structured