1. Some of the Many Applications of Archaeoclimatology Katherine McEnaney and Reid Bryson (The powerpoint will run itself automatically on the ‘slideshow’ setting)

2. Intro  Local  Large Scale  Storms  Dunes  Composite Archaeoclimatology l Sometimes called Macrophysical modeling l Tested hundreds of times against field data l Based on –orbital forcing of incoming radiation –modulation by aerosols and variable snow-ice albedo –standard dynamics –synoptic climatology

3. Intro  Local  Large Scale  Storms  Dunes  Composite Archaeoclimatology l Site specific l Yields monthly 200 year mean values l This makes the method unique l It [is now] possible to produce 100 year resolution for the past 20,000+ years

4. Intro  Local  Large Scale  Storms  Dunes  Composite Example: La Crosse, WI La Crosse appears to have had twice as much precipitation in Late Pleistocene and Early Holocene times Summer rains were less important in Mid Holocene Heaviest rains have shifted to summer

5. Intro  Local  Large Scale  Storms  Dunes  Composite Example: La Crosse, WI The difference between precipitation and evaporation is known as water stress Boreal Forests have an abundance of precipitation More recent times have a great deal of variability Grasslands have a deficit of precipitation

6. Intro  Local  Large Scale  Storms  Dunes  Composite Large Scale Features l Large scale features may be modeled –Sea Ice –Large River Discharge

7. Intro  Local  Large Scale  Storms  Dunes  Composite Large Scale Features l In the far north, human usage of an area seems to be related to sea ice

8. Intro  Local  Large Scale  Storms  Dunes  Composite Discharge of the Mississippi Intro  Local  Large Scale  Storms  Dunes  Composite

9. The Effect of the onset of the Holocene is obvious Northern Example: Dinwoody Creek, Wyoming Intro  Local  Large Scale  Storms  Dunes  Composite

10. Stream Discharge In Late Pleistocene time the river appears to have been frozen to the bottom with no winter discharge, even in May. The snowmelt of June produced an enormous freshet. In the warmer, less snowy, Holocene the freshet was greatly reduced and there was winter discharge. In the Holocene, there were times of greater discharge. These are associated with an increase in westerly storms, not local events.

11. Storms and Snow These storms also brought more snow Intro  Local  Large Scale  Storms  Dunes  Composite

12. l Hurricane or Typhoon frequency l Thunderstorm frequency l High Tropical Humidities l Changing Prevailing Winds, Dunes Farther south, there are different problems Intro  Local  Large Scale  Storms  Dunes  Composite

13. Hurricanes l Hurricanes are important –Winds and storm surges –Heavy rains from their residuals l Heavy Rains, “Gully-washers” are often associated with deep masses of moist air originating in Tropical Storms and intruding into the Westerlies

14. Intro  Local  Large Scale  Storms  Dunes  Composite Hurricanes Farther North Cape Cod

15. Intro  Local  Large Scale  Storms  Dunes  Composite Hurricanes Farther North l Tropical storm number can be modeled

16. Intro  Local  Large Scale  Storms  Dunes  Composite Modeled Fire Hazard l Thunderstorm frequency is important in areas prone to fires Intro  Local  Large Scale  Storms  Dunes  Composite

17. Modeled Fire Hazard Stormy with Dry Air Intro  Local  Large Scale  Storms  Dunes  Composite

18. Dune Movement Departure of ice from the Cochrane Moraine may have increased dune movement in Southern Manitoba

19. Intro  Local  Large Scale  Storms  Dunes  Composite Dune Movement Note the dramatic increase in drift potential after 8000

20. Intro  Local  Large Scale  Storms  Dunes  Composite Composite Studies l Models may be combined for a given state/region l The results may be used to map precipitation values or anomalies through the past

21. Intro  Local  Large Scale  Storms  Dunes  Composite In Summary l Almost any important climatic variable may be modeled l Models are site-specific and high resolution l Models are economical l There seem to be no competitive models

22. Intro  Local  Large Scale  Storms  Dunes  Composite Please cite as McEnaney, K. A. and R. A. Bryson 2005Some of the Many Applications of Archaeoclimatology. Paper presented at the Wisconsin Archaeological Survey Research Reports Meeting, April 23, 2005, Madison, WI. For more information, please contact rabryson@wisc.edu or kamcenaney@wisc.edu. rabryson@wisc.edu kamcenaney@wisc.edu rabryson@wisc.edu kamcenaney@wisc.edu