1. Walter Dean, USGS, Denver, Colorado, USA
History of sedimentation in Bear Lake, Utah and Idaho, USA, over the last 240,000 years: links to Pacific climate
Walter Dean, USGS, Denver, Colorado, USA 1

2. Elev. =
1845 m
Elev.=
1800 m

3. GLACIAL THROUGH HOLOCENE CHANGES IN CARBONATE DEPOSITION
1996 Kullenberg Piston Cores

6. O, C, and Sr isotopes in BL96-2
aragonite
qtz.
Glacial-age red, calcareous clay
Average Bear River sediment
80% quartz, 6% dolomite

7. In the US aragonite usually occurs in saline prairie lakes
Aragonite does not form in large, cold, deep, oligotrophic, high altitude, north temperate lakes fed by snowmelt!

8. CARBONATE DEPOSITION DURING THE LAST TWO GLACIAL-INTERGLACIAL CYCES
The 2000 GLAD800 cores

9. GLAD800 (aka R/V Kerry Kelts)
Bear Lake, Utah

11. Warm/dry
evaporation
BL00-1

17. Santa Barbara Basin

20. D/O 14
(Dean et al., 2006)

21. Greenland Ice

22. Depth (m)

24. Low product.
High product.
high runoff

25. El Nino

26. ENSO

27. Hadley Circulation

29. CONCLUSIONS
From the sediment record in Bear Lake it appears that the high-carbonate, aragonitic interglacial intervals in BL00-1 coincide with warm, dry continental climates, warm Pacific SSTs, and increased coastal upwelling recorded in cores from the OMZ off California and Mexico. This implies that the Subtropical High that drives the California Current Upwelling system today during the summer was a more permanent feature of the North Pacific during interglacials. During the LGI and other glacials the Aleutian Low, presently dominant during the winter, was a more permanent feature of the North Pacific, producing storms and precipitation that increased the levels of Lakes Lahontan and Bonneville, and increased the flow of the Bear River.

30. IMPLICATIONS
It is likely that the Atlantic and Pacific were linked through the atmosphere. Warmer interstadials would have strengthened Hadley and Walker circulations, which, in turn would have strengthened the subtropical high-pressure systems in both the North Pacific and North Atlantic, producing increased upwelling along the western margin of North America and increased precipitation over the Cariaco Basin. Increased Hadley and Walker circulations would have increased the amount of water vapor in the atmosphere, which potentially could have had a large effect on the global climate system.