1 / 72

Methane Paleoclimate & Milankovich

Methane Paleoclimate & Milankovich. Gerrit Lohmann Carbon Course 26. January 2006 @PEP, University of Bremen, Germany. 13-C Fractionation.

blaine
Télécharger la présentation

Methane Paleoclimate & Milankovich

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. MethanePaleoclimate & Milankovich Gerrit Lohmann Carbon Course 26. January 2006 @PEP, University of Bremen, Germany

  2. 13-C Fractionation • The photosynthetic activity in the oceans (photic zone) results in a very strong depletion of the surface waters in 12C (captured in organic matter), strong enrichment in 13C. • Planktonic organisms living in the photic zone, and forming calcareous shells from dissolved inorganic carbon (largely HCO3- ), thus use carbon that is enriched in 13C

  3. Organic Carbon cycle

  4. Organic Carbon cycle oxidation

  5. Photosynthesis -> low PO4, organic matter with 12-C, residual water high 13-C

  6. ``13-C conveyor belt´´

  7. Atlantic Ocean

  8. Pacific Ocean

  9. Pacific Ocean

  10. 13-C: Aging waters out of contact with the surface ocean for a long time: accumulated much carbon derived from oxidation of organic material thus their total dissolved inorganic carbon is isotopically light.

  11. Circulation and productivity

  12. 13-C: climate changes

  13. Interglacials=warm Lower photosynthesis 13-C surface-deep neg.

  14. Paleoclimate

  15. Paleoclimate

  16. Anomalien und Spektren

  17. Annual Cycle Northern Hemisphere Summer Boreal Summer

  18. Annual Cycle They have summer We have summer Northern Hemisphere Summer Boreal Summer

  19. Annual Cycle Fixed axis of Earth rotation

  20. Eccentricity

  21. Obliquity

  22. Precession & Eccentricity Present Orbital Configuration: Winter Solstice close to the position of Perihelion

  23. Precession

  24. One basic concept of ice ages: Recfification: Non-symetric response Ice albedo effect, Growth and decay of ice sheets

  25. Half Wave Rectification The incorporation of a single diode is the simplest way of rectifying AC.  Only the forward half-cycle is passed.  The reverse is blocked.  The rectified current is a series of pulses.  Task: calculate the Fourier transformation of the rectified signal in insolation, 20. June at 65 deg N

  26. Planets FORTRAN code based upon the Laskar solutionisat   http://xml.gsfc.nasa.gov/archive/catalogs/6/6063/index_long.html

  27. Threshold theory

  28. Questions: 1)Explain why periods of glacial advance in the higher latitudes tend to occur with warmer winters and cooler summers. 2) Are ice ages in the Northern Hemipshere more likely when: • a. the tilt of the earth is at a maximum or a minimum? • b. the sun is closest to the earth during summer in the Northern Hemisphere, or during winter?

  29. Effect on climate Rough locations of the Intertropical Convergence Zone (ITCZ) Southen margin of the Sahara Desert Congo Air Boundary (CAB)

More Related