1. Quaternary Environments Climate and Climatic Variation

2. Geologic Time Scale

3. Glacial Time Scales in the Northern Hemisphere

4. Blytt-Sernander Scheme of European Peat Stratigraphy

5. Scale of Variation

6. The Climate System  End-product of  Atmosphere  Oceans  Biosphere  Land surface  Cryosphere

7. Major Components of the Climate System

8. Atmosphere  Clouds  Atmospheric circulation  Greenhouse gasses (Water, Carbon Dioxide, Methane, Nitrous Oxides)  Temperature  Incoming solar radiation (INSOLATION)

9. Insolation (W/m 2 )

10. Oceans  Thermohaline Circulation  Thermal Inertia  Source of Moisture  Sea Level Rise  Melting of ice sheets  Thermal expansion

11. Thermohaline Circulation (Schmitz 1995)

12. Cross Section of Thermohaline Circulation (Brown et al. 1989)

13. Biosphere  Vegetation Effects on Climate  Albedo  Roughness  Evapotranspiration  Atmospheric composition  Vegetation Response to Climate  Faunal Response to Climate

14. CO 2 Sequestration

15. Land Surface  Effects of Land Surface on the Climate System  Aspect  Elevation  Albedo  Response to the Climate System  River systems  Sea level change  Glacial evidence

16. Cryosphere  Ice Extent  Albedo  Feedback Effects  Temperature Control

17. Energy Balance in the Atmosphere  Sensitive heat flux (H)  Latent heat flux (LE)  Bowen Ratio (H/LE)

18. Energy Balance

19. Time Scales of Climatic Variation  Climate Varies on All Time Scales  Driving Processes

20. Climate Variation Over Multiple Scales

21. Variations of the Earth’s Orbital Parameters  James Croll; Scottish natural historian 1867  Milankovitch; Elaborated on Croll’s original hypothesis in 1941  Berger; Advances Milankovitch’s work in the late 1970s

22. Milankovitch Cycles  Eccentricity – 95,800 year period. Changes in the orbital path of the Earth around the Sun. Affects the relative intensities of the seasons.  Obliquity – 41,000 year period. Changes in axial tilt of the Earth.  Precession – 21,700 year period. Wobble of the axis causing a precession of the equinoxes. Perihelion during Northern Hemisphere summer occurred 11,000 years ago.

23. Orbital Factors

24. Wobble on the Earth’s Axis

25. Precession

26. Insolation and 18 O

27. Long Term Solar Radiation

28. http://www-istp.gsfc.nasa.gov/Education/Intro.htmlhttp://www-istp.gsfc.nasa.gov/Education/Intro.html; Illustration by Steele Hill