1. Introduction into the Absorption Channels
Description of characteristics and content of the CO2 channel: Ch11: 
Contact person:
Veronika Zwatz-Meise
Version July 2004

2. All MSG channels Channel 01: VIS 0.6  Channel 02: VIS 0.8 
Channel 03: NIR 1.6 
Channel 04: MIR 3.9 
Channel 05 WV 
Channel 06: WV 
Channel 07: IR 
Channel 08: IR  („Ozon“)
Channel 09: IR 
Channel 10: IR 
Channel 11: IR  („CO2“)
Chanell 12: HRV (High Resolution Visible)

3. „CO2 channel“ Ch11: 13.4 m

4. Ch11: 13.4  Sun radiation Earth radiation Watt/ m2 and micron Ozone
Carbon
dioxid
Water
vapour
Wavelength (micron)

5. Comparison of radiation sources sun - earth
For wave length < 5 m solar radiation is dominant
For wave length > 5 m radiation of earth is dominant
Ch01, 02, 03, 12: only sun radiation
Ch04: both: radiation from sun and earth
Ch 05, 06, 07, 08, 09, 10, 11: only thermal earth radiation
Sun radiation Earth radiation
Watt/ m2
and
micron
only
VIS
VIS + IR
only IR

6. Ch11 is in the wing of the CO2 absorption band around 15 m
Energy
spectrum
Source: EUMETSAT
Ch11
Ch11 is in the wing of the CO2 absorption band around 15 m

7. Maximal signal from around 870 hPa
Weighting
functions
Source: EUMETSAT

8. Maximal signal from around 820 hPa
Weighting
functions
Source: EUMETSAT
Figure 3d

9. Application areas for the CO2 channel
Qualitative application of images:
No additional features compared to the IR window channels
No special application for qualitative image interpretation (at the time being)
Quantitative applications:
temperature profiles
instability
winds

10. Ch11:13.4

11. Ch09:10.8

12. Ch10:12.0