1. Quaternary Environments Paleoclimate Models

2. Types of Models  Simplify a system to its basic components  Types of Models  Physical Models  Globe  Statistical Models  Regression Equations  Conceptual Models  Flow chart  Computer Models  GCMs  Test Hypotheses

3. Types of Models  Energy Balance Models (EBMs) – Surface temperature as a result of energy balance  Zero-Dimension – Whole Earth  One-Dimension – Earth in zonal bands with latitudinal heat transfer  Two-Dimensions – Lat/Long or Latitude/Altitude changes  Statistical –Dynamical Models (SDMs)  Use parameterized input equations to describe changes through time  Radiative Convective Models (RCMs)  Radiative processes in vertical columns  General Circulation Models (GCMs)  Use physical laws to drive all changes  Coupled Ocean-Atmosphere GCMs

4. Statistical-Dynamical Model of variations of Northern Hemisphere ice volume over the last 200,000 years forced by CO 2 and Insolation

5. Schematic Diagram of atmosphere and ocean computational boxes in a coupled GCM

6. Levels of Complexity and Coupling of Ocean-Atmosphere Models

7. Problems With Current Models  Expense and Time  Resolution  Unknown Quantities  Cloud cover and feedback  Difference in response times between various components of the model  Lacking land surface, cryosphere, biogeochemical cycles, and biome components  Climate System Models (CSMs) being developed

8. http://www.cru.uea.ac.uk/cru/info/scen/

9. Estimated Response and Equilibrium Times for Different Components of the Climate System

10. Model Experiments  Are changes in orbital parameters enough to cause a glacial event?  Insolation as an input  Also needed increased cloudiness, increased soil moister, a shallow mixed layer in the ocean, and lower CO 2  Feedbacks include increased sea ice, lower SSTs in summer, and presence of permanent snow cover on land

11. Difference in Solar Radiation at the Top of the Atmosphere 115 kya

12. Modeled Snow Depth in August for 115 kya

13. Input Parameters for COHMAP Simulation

14. Output from COHMAP, Split Jet Stream During LGM

15. Modeling Forward  Models can be tested against paleorecords then these models can be used to predict future change  Multiple model outputs to estimate future change

16. http://www.cccma.bc.ec.gc.ca/models/cgcm2.shtml

17. Two Environment Canada models showing change from 1971-1990 to 2041-2060. Differences are based on a change in the depth and vigor of vertical mixing in the Southern Ocean

18. Climatic Research Unit, University of East Anglia http://www.cru.uea.ac.uk/ Scaling down from a GCM through a Regional Climate Model to the landscape