1. 1 Introduction into the Absorption Channels Description of characteristics and content of the CO2 channel: Ch11: 13.4  Contact person: Veronika Zwatz-Meise zwatz-meise@zamg.ac.at Version 1.0. 13 July 2004

2. 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 05WV 6.2  Channel 06:WV 7.3  Channel 07:IR 8.7  Channel 08:IR 9.7  („Ozon“) Channel 09:IR 10.8  Channel 10:IR 12.0  Channel 11:IR 13.4  („CO 2 “) Chanell 12:HRV (High Resolution Visible)

3. 3 „ CO2 channel“ Ch11: 13.4  m

4. 4 Sun radiation Earth radiation Ch11: 13.4  Wavelength (micron) Watt/ m 2 and micron Ozone Carbon dioxid Water vapour

5. 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 only VIS VIS + IR only IR 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/ m 2 and micron

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

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

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

9. 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. 10 Ch11:13.4

11. 11 Ch09:10.8

12. 12 Ch10:12.0