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-Meisezwatz-meise@zamg.ac.atVersion 1.0. 13 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 throughimproved space resolution

CF

Grey: warmcloud tops

White: coldcloud 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: highalbedo

CFGrey:transparent

9

MSG: Ch02

Compared to Ch01:no strong differences in the cloudfeatures over the ocean;but: much better land recognition

CF

10

MTP:VIS(2x)+IR

CF

11

MSG:129

Sharper contours and more detailed grey-shadesthrough 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

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;in IR detectable only fromgeneral structure

14

MSG: Ch09

Sharper contours throughimproved space resolution

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;in IR detectable only fromgeneral structure

15

MTP: vis

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;in vis differentiation between thickand transparent cloud parts possible

16

MSG: Ch01Looks relatively similar;but: somewhat coarser space resolution

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;in vis differentiation between thickand transparent cloud parts possible

17

MSG: Ch02

Compared to Ch01:no strong differences in the cloudfeatures over the ocean;but: much better land recognition

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;in vis differentiation between thickand transparent cloud parts possible

18

MTP:VIS(2x)+IR

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;blue: high cloud on anticyclonic jet sidegrey: thick cloud parts

19

MSG:129

Sharper contours and more detailed grey-shadesthrough improved space resolution in IR and additional information from 2 different VIS channels

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;blue: high cloud on anticyclonic jet sidegrey: thick cloud partsline of lower cloud cellsdiscernable

20

MTP: wv

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;jet axis through dark stripewell recognisable

21

MSG: Ch05

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;jet axis through dark stripewell recognisable

22

MSG: Ch06

CF

CF

Typical intensificationof front cloud on cyclonic side of a crossing jet streak;

Ch06:Signals from much lower downin tropopshere;black stripe crossing frontal cloud band less good butstill 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 atrearward 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 partof frontal cloud

CA

27

Isotachs 300

Jetaxis and jet streak alongrearward side of frontal cloud band

28

MSG: Ch05zeroline 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: Ch06zeroline of shear vort 300 (yellow)

30

MSG:139zeroline of shear vort. 300 (black)

Zeroline of shear vorticity 300(jetaxis) fits to the margentafibre 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 TFPclose to rear side of frontalcloud band as well as in the intensification area;

33

TA (red)

Main part of the frontalcloud band is under WA at 700

34

Isotachs (yellow) + PVA (red) at 300

A jet streak crosses thefront at the N-S oriented part;the intensification area is under strong PVA in the leftexit region of the jet streak

PVA max

35

MSG: Ch09zeroline of shear vort 300 (black)

The jet axis (zeroline ofshear vort. At 300) crosses thecloud band at the N-S oriented part

36

MSG: Ch05zeroline of shear vort 300 (black)

The jet axis (zeroline ofshear vort. at 300) is close tothe dark stripe in WV

37

MSG: Ch06zeroline of shear vort 300 (black)

The jet axis (zeroline ofshear vort. at 300) is close tothe dark stripe in WV;but: it is drier than in the upper WV channel; sometilt 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 cloudline at the rearward edge

CF

41

MSG: Ch03

CF

Ice clouds are superimposedon water clouds;line of ice clouds along rearward edge of frontal cloud band

42

MSG:321

Grey shades: from Vis channelsCyan: 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 cloudMagenta: ice cloudline of ice cloud alongrearward 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 theintesification area

48

MSG: Ch03

Ice clouds are superimposedon water clouds;intensification area consistsof ice and water cloud

49

MSG:321Grey shades: from Vis channelsCyan: represents the ice clouds from Ch03:intensification area shows ice on topof water cloud

50

MSG: Ch04

Black: cold cloud tops

51

MSG:139Blue: cold transparent cloudMagenta: ice cloudintensification area is magenta

52

MSG:134

Brown/orange: cold cloud top;ice cloud;intensification area isbrown structured