1. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Climate Change in the Geologic Record Miriam S. Andres, Angela Hessler, Tim McHargue Carbonate Research & Development Team ETC-Chevron, San Ramon December 2009

2. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 2 Taken from Ruddiman: Earth’s Climate: Past and Future

3. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Temperature in the Geologic Record 3 www.wikipedia.org

4. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Temperature in the Geologic Record – A Matter of Time Scales 4 www.wikipedia.org PETM Anthropocene Younger Dryas Cretaceous Supergreenhouse

5. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 5 The Cretaceous – Super Greenhouse Climate 2011 (389 pp) 2000-1000 ppm; 8x pre-industrial levels High sea level; abundant inundated shallow shelf areas. one-third of Earth's present land area was submerged Taken from Ruddiman: Earth’s Climate: Past and Future

6. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 6 The Cretaceous – Super Greenhouse Climate Why did it not get warmer and warmer? Taken from Ruddiman: Earth’s Climate: Past and Future

7. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Temperature in the Geologic Record – A Matter of Time Scales 7 www.wikipedia.org PETM Anthropocene Younger Dryas Cretaceous Supergreenhouse

8. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Paleocene-Eocene Thermal Maximum ~56Ma 8 Taken from National Geographic, October 2011

9. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 9 Taken from National Geographic, October 2011

10. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 10 Taken from National Geographic, October 2011

11. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 11 Taken from National Geographic, October 2011

12. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 PETM vs. current warming 12 Source: http://www.wunderground.com/climate/PETM

13. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Comparison 13 Source: http://www.wunderground.com/climate/PETM

14. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Temperature in the Geologic Record – A Matter of Time Scales 14 www.wikipedia.org PETM Anthropocene Younger Dryas Cretaceous Supergreenhouse

15. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 The End of the Last Glacial 15 Ice retreating but then… Taken from Ruddiman: Earth’s Climate: Past and Future

16. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 The Younger Dryas – return to glacial conditions 16 The 90 Minute Hollywood Version

17. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 17 The prevailing theory holds that the Younger Dryas was caused by a significant reduction or shutdown of the North Atlantic thermohaline circulation in response to a sudden influx of fresh water from Lake Agassiz (size of UK) and deglaciation in North America. But still a lot of uncertainty and contradicting data sets. -> Bolide impact? -> Other outflows? A Lake? Are you serious? Mark Bateman, Sheffield University

18. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 18 Rate of change: Temperature drop within a human life span (~30yrs) Global effects: not always cooling, but sometimes drought Summit of Greenland was ~15°C colder during the Younger Dryas than today. In the UK, (fossil beetle) evidence suggests mean annual temperature dropped to approximately 5°C, and periglacial conditions prevailed in lowland areas, while icefields and glaciers formed in upland areas. Whatever the cause – the result impressive: www.earthtimes.orgShakun & Carlson, 2010

19. Climate Change Workshop – BAESI – 5 th Nov. 2011 © Chevron 2011 Temperature in the Geologic Record – A Matter of Time Scales 19 www.wikipedia.org PETM Anthropocene Younger Dryas Cretaceous Supergreenhouse