1. Paleoceanography Antarctica Circumpolar Current:

2. Paleoceanography Antarctica Circumpolar Current:

3. Paleoceanography Antarctica Circumpolar Current:

4. Paleoceanography Antarctica Circumpolar Current: Guembelitria samwelli

5. Paleoceanography Antarctica Circumpolar Current:

6. Paleoceanography Use Isotopes to measure paleoceanography:

7. Paleoceanography Unstable Isotopes:

8. Paleoceanography Use Isotopes to measure paleoceanography:

9. Paleoceanography Stable Isotopes: Given in parts per thousand ( o / oo ) values reported relative to a standard SMOW = standard mean ocean water  ( o / oo ) = ratio sample -1 x 1000 ratio standard

10. Paleoceanography Stable Isotopes: –Evaporation favors light isotope –Evaporation of seawater leaves oceans “isotopically heavier” –Precipitation favors heavy isotope –Production of organic matter favors light isotope

11. Paleoceanography Temperature variation in fractionation of 18 O:

12. Paleoceanography Temperature variation in fractionation of 18 O:

13. Paleoceanography Measuring SST

14. Paleoceanography Problem

15. Paleoceanography Fractionation:  18 O = 0

16. Paleoceanography Modern global surface seawater  18 Osmow :

17. Paleoceanography Infers changes in ice volume

18. Paleoceanography More global ice isotopically heavier ocean reservoir Less global ice isotopically lighter ocean reservoir

19. Ice Ages

20. What causes Interglacial/Glacial Cycles? 1.Fluctuations in the amount of insolation (incoming solar radiation) 2.Location of continents relative to polar regions 3.Location of precipitation belts relative to location of continents 4.Vigor of thermohaline circulation

21. Paleoceanography Coral rings :

22. Paleoceanography Coral rings :