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What was the Lake El’gygytgyn Drilling Project, NE Russia:
What does it mean for understanding Arctic Climate Evolution? Arctic Vulnerability to Climate Variability over the past 3.6 Myr: Lessons from sediments drilled at El’gygytgyn Crater Lake, Western Beringia Julie Brigham-Grette, UMASS -Amherst Martin Melles, Univ of Cologne Pavel Minyuk, NEISRI-Magadan and El’gygytgyn Science Party
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Also mention: warming T, melting permafrost, surging glaciers, earlier spring, longer growing season…this is all because of the…change slide
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Leg 323
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- Drilling Operation - M J A S O N D F 2010 2009 2008 1st transport
to Lake E Camp set up
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- Drilling Operation - M J A S O N D F 2010 2009 2008 lake drilling
2nd transport to Lake E Permafrost drilling (D3) 1st transport Camp set up ice road & thickening
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How do I study Arctic climate – lake sediments
11/16/2018
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Picture courtesy of the Arctic Climate Impact ssessment
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100 kyrs 41 kyrs 21 & 23 kyrs
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MIS 31 orbital parameters
Lisiecki and Raymo, 2005; Laskar, 2004
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ANDRILL Lake El’gygytgyn Polar Programs with International partners
With New Zealand, UK, Italy, Germany, With Germany, Russia, Austria Photos from Catalina Gebhardt, AWI
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A record of past WAIS behavior
ANDRILL MIS Naish, Powell, Levy, DeConto, and Harwood et al ANDRILL( ) platform on McMurdo Ice Shelf Recovered ~1200 m of sediment, ~14 Ma to present Best proximal record of ice sheet variations through last few million years Diatomaceous ooze Tills/diamict
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ANDRILL MIS Core, upper 600 m (~0-5 Ma)
Main Results from Drilling WAIS has been dynamic, advancing and retreating on ~40 kyr obliquity cycles Long-term trends: - Modern glacials, 1 to 0 Ma - Cooling transition, 3 to 1.5 Ma - Warmest in early Pliocene, extended interglacials, 5 to 3.5 Ma 2 1 3 4 5 Lithologic log Approx. Age Depth (Ma) (mbsf) Stage 31 in Antarctica No WAIS M2 interval Yellow = open ocean (diatomite) Green = grounded ice (diamictite) Grey = proximal GL (mud/silt/sand) Orange = volcanic Naish et al., Nature., 2009
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Otto-Bleisner et al. (2006) simulation
MIS 5e Smaller GIS Otto-Bleisner et al. (2006) simulation MIS 11 and 31 no GIS ? S. Funder, in Miller et al, 2010
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Lake E super interglacials = No WAIS?
Melles, Brigham-Grette, Minyuk et al, 2012, Science
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Ron Blakey paleogeography Ron Blakey paleogeography
Sites Age 1. Nome Ma 2. Gubik Fm Ma 3. Lost Chicken ~ 2.9 Ma 4. Klondike Area Ma 5. Ballast Brook Ma 6. Meighen Island ~ 3.2 Ma 7. Hvitland Beds ~ Ma 8. Strathcona Fjord ~3.4 Ma 9. Kap Kobenhaven 2 – 2.5 Ma 10. Loden Elv Fm. ~2.4 Ma Ron Blakey paleogeography Ron Blakey paleogeography
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So, The warmth that dominated the Pliocene and early Pleistocene suggest s
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1. This is the first continuous record of the Middle Pliocene documenting sustained warmth with summer temperatures in the range of 15-16oC and precipitation 3 times higher than today. We show that this warmth occurred throughout both warm and cold orbital cycles and coincides in part with a long interval of 1.2 Myrs when the West Antarctic Ice Sheet did not exist. 2. The first major “cold snap” at the lake ~ 3.3 Ma, coincides precisely with the major marine isotopic shift known as “M2”. Yet during this interval, temperatures in the western Arctic were similar to the Holocene average. Most importantly, conditions in the terrestrial Arctic were not “glacial” in character, raising new questions as to the nature and timing of early glaciation on Greenland and the wider circum-Arctic. 3. We provide the first long terrestrial record for comparison with the well studied PRISM interval from about 3 to 3.2 Ma (Dowsett et al., 2010) and suggest that ensemble climate model runs of this interval come close, but do not fully capture the polar amplification recorded at Lake El’gygytgyn. 4. We show from a terrestrial perspective the stepped pacing of the transition from a warm, forested Arctic to glacial onset. What is impressive is that summer temperatures during warm intervals were always much warmer than the Holocene even as late as 2.2 Ma, and a major drop in Arctic precipitation occurs precisely when the North Pacific Ocean becomes highly stratified (Haug et al. 2005; Studer et al. 2012). This has major implications for understanding both the timing and character of early Northern Hemispheric glaciation, and model-based reconstructions of seasonal vs. perennial Arctic sea in a world warmer than today. 5. Finally, our paleoclimate reconstructions and modeling efforts are broadly consistent with estimates of atmospheric CO2 given by Pagani et al. (2009), who suggest that Pliocene CO2 was in the range of 360 to 400 ppm and did not drop below 320 ppm until after 2.2 Ma. However, the inability of coupled GCMs to match the peak Pliocene warmth at the lake, lends support to ideas suggesting that CO2 sensitivity may well be much higher than suggested by the IPCC AR4.
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