1 / 35

Air-Sea Interactions

Air-Sea Interactions. Martin Visbeck Department of Earth and Environmental Sciences, LDEO, Columbia University http://www.ldeo.columbia.edu/~visbeck Why Is Europe Warmer than Canada? The Gulf Stream vs. Atmospheric Winds. IS EUROPE WARMER THAN CANADA?. Evidence from Global Data

turi
Télécharger la présentation

Air-Sea Interactions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Air-Sea Interactions Martin Visbeck Department of Earth and Environmental Sciences,LDEO, Columbia Universityhttp://www.ldeo.columbia.edu/~visbeck Why Is Europe Warmer than Canada? The Gulf Stream vs. Atmospheric Winds

  2. IS EUROPE WARMER THAN CANADA? • Evidence from Global Data • For example you can use http://ingrid.ldeo.columbia.edu • compute zonal mean anomaly

  3. Climatological January Temp. Convinced ?

  4. Winter Temp. Atlantic

  5. Winter Temp. Atlantic (2) Temp.differencebetweenpointsis: 18 Cor32 F Here the zonal mean Temp. is removed

  6. WHY? • Where does the energy come from? • What sets the energy balance? • How is it distributed? • Why is the temperature different at the same latitude?

  7. Climate Forcing

  8. WHY? • Where does the energy come from? • What sets the energy balance? • How is it distributed? • Why is the temperature different at the same latitude?

  9. Radiative Energy Balance Short waveradiationcomes in… Long waveradiationgoes out… water vaporis green house gas

  10. Radiative Energy Balance (2) Short waveradiationcomes in… Long waveradiationgoes out…

  11. Radiative Energy Balance (2) The imbalance of the top of the atmosphere radiation implies that there must be an internal heat transport by the combined action of ocean and atmosphere of ~6 1015 W 30°N/S.

  12. WHY? • Where does the energy come from? • What sets the energy balance? • How is it distributed? • Why is the temperature different at the same latitude?

  13. Atmospheric Heat Transport

  14. Atmospheric Heat Transportsimulation in tank light Cool water

  15. Atmospheric Heat Transportsimulation in tank light Cool water Warm Cold

  16. Atmospheric Heat Transportsimulation in tank What do we miss? The rotation of the planetintroduces a new force: The Coriolis Force Warm Cold

  17. Global Wind System

  18. Global Wind System

  19. Global Wind and Cloud System

  20. WHY? • Where does the energy come from? • What sets the energy balance? • How is it distributed? How much is due to the atmospheric circulation? How much is due to the ocean’s circulation? • Why is the temperature different at the same latitude?

  21. Ocean Surface Temperature (SST)

  22. Ocean Surface Currents

  23. The Gulf Stream / North Atlantic Current

  24. Oceanic Temperature Structure

  25. Ocean Heat Transportsimulation in tank light Cool water

  26. light Cool water Warm Cold Ocean Heat Transportsimulation in tank (2)

  27. Oceanic Heat Transport

  28. Oceanic Heat Transport Ocean warms Atmosphere Ocean is warmed by Sun Black numbers are ocean heat transport in PW

  29. WHY? • Where does the energy come from? • What sets the energy balance? • How is it distributed? • Why is the temperature different at the same latitude?

  30. Winter Atmospheric Circulation

  31. Winter Atmospheric Circulation Cold Warm

  32. Winter Heat Transport The Atmosphere has whatwe call standing waves whichare able to preferentially heat parts of the planet. The current scientific debateis on what causes theirexistence. Either mountainsor air-sea temperature difference or a combinationof both.

  33. Winter Heat Transport The Atmosphere transportsabout 5/6 of the heat polewardin the global mean. However, in the Atlantic sectorthe ocean is believed to carryabout 1/2. There is debate about who is most responsible for changesin the poleward heat transport.Weather this is in an ice-ageor global warming context.

  34. Some Final Remarks • The atmosphere carries: • 78 percent of the heat transport in the Northern Hemisphere and • 92 percent in the Southern Hemisphere at 35 degrees latitude, where the heat transport peaks. • It would take a million 1,000-megawatt electric power stations - the largest power plants now used - to produce a quantity of energy equivalent to the heat the atmosphere carries on average from the tropics to polar regions.

  35. Atmosphere-Ocean Heat Transportsimulation in tank light Cool water Warm Atmosphere Cold Warm Ocean Cold

More Related