1. Ice Cores • Very important paleoclimatic archives. • Records of past atmospheric conditions. • Temperature • Humidity • Snow accumulation • Atmospheric composition • Volcanic activity • Tropospheric turbidity • Wind speed, wind direction • Atmospheric circulation

3. Ice Core drilling

8. Stable Isotopes-Concepts • Name Symbol Definition • Atomic number Z # protons (p+) • Neutron number N # neutrons (n) • Mass number A # p+ + n

9. Abundance of stable isotopes of water

11. Physical properties of water

12. Isotope effect and fractionation • Isotopes undergo the same chemical and physical reactions. • The rate of these reactions, however, could be different (isotope effect), resulting in the partitioning of isotopes (fractionation).

13. Terminology d=1000(Rsample/Rstandard – 1) where R=heavy isotope/lighter isotope d18O= 1000(18Rsample/18Rstandard – 1) where 18R=18O/16O dD= 1000(2Rsample/2Rstandard – 1) where 2R=D/H Standard is V-SMOW (Vienna-Standard Meteoric Ocean Water). d18OV-SMOW = dDV-SMOW = 0‰

16. Temperature Altitude Distance from the source Latitude IAEA (2001).  GNIP Maps and Animations.

17. IAEA (2001).  GNIP Maps and Animations

18. IAEA (2001).  GNIP Maps and Animations

20. Fricke and O’Neil, 1999

23. Edwards et al., 2004

24. d-excess • Meteoric Water Line: dD=8*d18O+10 d-excess under “normal” conditions d= dD-8*d18O Increased relative humidity or lower sea-surface temperature (reduced evaporation rates) produces lower d-excess values.

26. Dating Ice Cores • Radio-isotopes • Ice layers • Ice flow models • Reference horizons

27. Volcanic markers provide additional time control

28. Seasonal variations can be detected with microparticles and glacio-chemical data

29. Antarctic Ice Cores

30. Vostok Ice Core

33. Epica Group, 2004

34. Epica Group, 2004

35. Epica Group, 2004

39. Greenland

42. MIS-4 MIS-1 MIS-3 MIS-5 Blunier and Brook, 2001, Science

50. Colder/Drier? Warmer/Wetter?