1. Cours #2 : Radiation • Overview Earth radiation Budget (Trenbergh et al., 1997 and 2008) • Climate forcings and feedback mechanisms • Earth Radiation Budget at regional scale (from CERES EBAF) • The GERB project (hsaf.ppt / Lille.ppt ) • Exercices : use of LibRadTran to simulate solar and thermal radiation.

2. Climate System Energy Balance

3. GPCP 76 W m-2 2000-2005 Trenberth et al 2009

4. Radiative Forcing from 1750 to 2000 Anthropogenic Forcings IPCC, 2001

5. How does the Earth Respond? Earth System Response Forces Acting On the Earth System IMPACTS Feedback Of the total forcing of the climate system, 40% is due to the direct effect of greenhouse gases and aerosols, and 60% is from feedback effects, such as increasing concentrations of water vapor as temperature rises.

6. Global Atmospheric Circulation

7. Reflected solar radiation

8. Emitted thermal radiation

9. Total outgoing radiation

10. Net incoming radiation

11. OLR

12. Change OLR: last 5 years – first 5 years

13. Yearly animation OLR

14. El Nino / La Nina years

15. Variation OLR: La Nina years – El Nino years