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Understanding Artic Climate Evolution
- 1. What was the Lake El’gygytgyn Drilling Project, NE Russia: What does it mean for understanding Arctic Climate Evolution? Julie Brigham-Grette, UMASS -Amherst Martin Melles, Univ of Cologne Pavel Minyuk, NEISRI-Magadan and El’gygytgyn Science Party
- 2. Career of Understanding Cenozoic Climate History of the Arctic
- 3. Created by Bill Manley, INSTAAR
- 4. ….3.6 Million Years ago (Middle Pliocene)
- 5. 5 Location- central Chukotka LakeLake ElEl‘‘gygytgyngygytgyn LakeLake ElEl‘‘gygytgyngygytgyn Meteorite Impact Lake created 3.58+/- 0.04 Ma (Layer 2000) Leg 323
- 6. 6 Drilling and Science Team (day and night shifts) Science, drilling, and Russian camp staff Group Success!
- 8. 8 1998 Expedition 2000 Expedition 2003 Expedition Three Site Survey expeditions 2 trips to Moscow Every year for 4-5 years = lots of Vodka Frank Rack
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- 15. 15 11stst transporttransport to Lake Eto Lake E CCampamp sset upet up M J J A S O N D J F M A M J J A S O N D J F M A 201020092008 - Drilling Operation -- Drilling Operation -
- 16. 16 lakelake drillingdrilling 22ndnd transporttransport to Lake Eto Lake E PermafrostPermafrost drilling (D3)drilling (D3) 11stst transporttransport to Lake Eto Lake E CCampamp sset upet up iice roadce road & thickening& thickening M J J A S O N D J F M A M J J A S O N D J F M A 201020092008 - Drilling Operation -- Drilling Operation -
- 17. 17 How do I study Arctic climate – lake sediments Ab an MI (20 nu int da co slic 05/21/15 17
- 18. 18Picture courtesy of the Arctic Climate Impact Assessment 3.6 Ma = Peak of Pliocene Warming Greenland courtesy of Svend Funder
- 19. 19 Drilling Targets – continuous to 3.6 Ma Most continuous record in terrestrial Arctic!
- 20. - Results-- Results- (2) Long-term History > -4°C Nolan (2012) -- δ13TOC Summer Winter + TOC + TN + TOC/TN + TS + clasts. + laminae H2S H2S H2S H2S H2S H2S H2S H2S H2S +/- opal cold and dry permanent ice cover rel. low primary production anoxic bottom water some terrestr. org. supply 13.5 13.6 Field depth (mblf) Line scan picture X-radiograph 13.7 -- δ13TOC Summer Winter + laminae - clasts. + TOC + TN +/- TOC/TN + TS H2S H2S H2S H2S H2S H2S H2S H2S H2S - opal cold and moist perm. ice cover with snow low primary production anoxic bottom water some terrestr. org. supply Field depth (mblf) 9.29.1 9.3 Line scan picture X-radiograph after Melles et al. (2007)
- 21. - Results-- Results- (2) Long-term History after Melles et al. (2007) +/- δ13TOC Summer Winter +/- TOC +/- TN + TOC/TN - TS - clasts. + bioturb. + opal peak warm semipermanent ice cover high primary production oxygenated bottom water high terrestr. org. supply Field depth (mblf) 58.658.5 58.7 Line scan picture X-radiograph Line scan picture X-radiograph 9.6 9.7 Field depth (mblf) 9.5 + δ13TOC Summer Winter - TOC - TN - TOC/TN - TS - clasts. + bioturb. +/- opal warm semipermanent ice cover rel. high primary production oxygenated bottom water low terrestr. org. supply
- 22. 100 kyrs 41 kyrs 21 & 23 kyrs
- 23. MIS 31 orbital parameters Lisiecki and Raymo, 2005; Laskar, 2004
- 25. Conclusions: Key points and Scientific Firsts 1. First continuous record of Middle Pliocene with sustained summer temperatures in range of 15- 16o C and precipitation 3 times higher than today. Warmth occurred throughout both warm and cold orbital cycles 2. New evidence of 17 super interglacials in Arctic that might be tied to times of Antarctic ice retreat. 3. Stepped pacing of the transition from a warm, forested Arctic to glacial onset, esp. 2.4 to 2.8 ma 4. Finally, paleoclimate reconstructions consistent with estimates of atmospheric pCO2
Editor's Notes
- Arctic Vulnerability to Climate Variability over the past 3.6 Myr: Lessons from sediments drilled at El’gygytgyn Crater Lake, Western Beringia
- Also mention: warming T, melting permafrost, surging glaciers, earlier spring, longer growing season…this is all because of the…change slide
- Photos from Catalina Gebhardt, AWI
- So, The warmth that dominated the Pliocene and early Pleistocene suggest s
- 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.