Energy in the Ocean-Atmosphere Climate System

1. Energy in the Ocean-Atmosphere Climate System SOEE3410 : Lecture 2 Dr Ian Brooks i.brooks@see.leeds.ac.uk Room 1.64a Environment Building http://homepages.see.leeds.ac.uk/~ibrooks

2. The atmosphere-ocean system acts as a heat engine • Energy OUT = Energy IN • Work done  moving atmosphere and ocean around Energy OUT(heat lost to space as infra-red radiation) Energy IN(solar radiation) Work done SOEE3410 : Atmosphere and Ocean Climate Change

3. Contributions to global ocean-atmosphere energy budget SOEE3410 : Atmosphere and Ocean Climate Change

4. reflected solar radiation 107 W m2 Incoming solar radiation 342 W m2 Outgoing longwave radiation 235 W m2 40 Reflected by clouds, aerosol & atmosphere 30 165 77 emitted by atmosphere Absorbed by atmosphere 67 78 350 24 back radiation 324 Reflected by surface 40 30 324 78 390 168 24 thermals Absorbed by surface Evapo-transpiration Absorbed by surface Surface radiation SOEE3410 : Atmosphere and Ocean Climate Change

5. IPCC : http://www.ipcc.ch/present/graphics.htm SOEE3410 : Atmosphere and Ocean Climate Change

6. 4 12 16 0 2 6 8 10 14 18 14.5 Heat absorbed by the oceans 0.9 Heat absorbed by the continents (Beltrami et al. 2002) 0.8 Heat required to melt continental glaciers at estimated maximum melting rate (Houghton et al. 2001) 0.7 Heat absorbed by the atmosphere during 1955-96 (Levitus et al. 2001) 0.3 Heat required to reduce Antarctic sea-ice extent (de la Mare, 1997) 0.1 Heat required to melt mountain glaciers at estimated maximum melting rate (Houghton et al. 2001) 0.005 Heat require to melt northern hemisphere sea-ice (Parkinson et al. 1999) 0.002 Heat require to melt Arctic perennial sea-ice volume (Rotherock et al. 1999) Estimate of Earth’s heat balance components (1022 J) for the period 1955-1988 (after Levitus et al, 2005, GRL, VOL. 32, L02604, doi:10.1029/2004GL021592) SOEE3410 : Atmosphere and Ocean Climate Change

7. No Atmosphere SWi = Solar (shortwave) radiation SWr = shortwave reflected LWe = Infra red (longwave) emitted radiation = Ts4 Ts = surface temperature  = Stefan-Boltzman constant (5.67 x 10-8 Watts m-2 K-4 ) At equilibrium… SWi = SWr + LWe SWi SWr LWe Ts In the absence of an atmosphere the surface temperature of earth would be approximately 255K (-18ºC). It’s actual mean temperature is 288K (+15ºC) SOEE3410 : Atmosphere and Ocean Climate Change

8. CO2 Some radiation passes through atmosphere Some radiation absorbed by gas molecules Radiation absorbed from ONE direction, heating gas, is re-emitted in ALL directions SOEE3410 : Atmosphere and Ocean Climate Change

9. 90 60 30 0 30 60 90 Ferrel Cell Polar Cell Net Radiation Heat Transport Idealized model of atmospheric circulation.N.B. actual circulations are not continuous in space or time. SOEE3410 : Atmosphere and Ocean Climate Change

10. 60° 30° 0° Mid-latitudeJet Stream Polar Front Tropicaljet Deep convection SOEE3410 : Atmosphere and Ocean Climate Change

11. SOEE3410 : Atmosphere and Ocean Climate Change

12. IPCC : http://www.ipcc.ch/present/graphics.htm SOEE3410 : Atmosphere and Ocean Climate Change

13. Animation of monthly net Short-Wave (solar) radiation (W/m2) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

14. Animation of monthly net Long-Wave (infra-red) radiation (W/m2) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

15. Animation of monthly net radiation (W/m2) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

16. Animation of monthly sensible heat flux (W/m2) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

17. Animation of monthly latent heat flux (W/m2) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

18. Animation of monthly change in heat storage (W/m2) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

19. From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

20. Animation of monthly surface temperature (ºC) From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

21. Animation of monthly sea-level pressure (mb) and surface winds From http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change

22. Suphate aerosols deposited in Greenland ice Concentrations of 3 well-mixed greenhouse gases SOEE3410 : Atmosphere and Ocean Climate Change

23. Increases in greenhouse gas concentrations change the radiative balance of the earth by reducing the outgoing longwave radiation. • The climate system must adjust to a new equilibrium. • The nature of the change in climate state is complicated by the large number of interacting processes. SOEE3410 : Atmosphere and Ocean Climate Change

24. Online Resources • The animations shown in this lecture have been made available at http://homepages.see.leeds.ac.uk/~ibrooks/envi3410 • The were produced by the Department of Geography at the University of Oregon. These and some additional animations can be found at : http://geography.uoregon.edu/envchange/clim_animations/index.html SOEE3410 : Atmosphere and Ocean Climate Change