EPOCA Kick-off Meeting June 2008: Nice

1. EPOCA Kick-off Meeting June 2008: Nice Theme 1 Ocean chemistry and biogeography What is the past and recent variability of ocean carbonate chemistry (including nutrients and trace metals) and geographical distribution of marine organisms? Among other methods, paleo-reconstructions will be used to investigate the response of (mainly) calcifying organisms to past changes in ocean acidification.

2. WP2 Past variability of ocean chemistry (paleo-reconstruction) Objectives Determine oceanic carbonate chemistry evolution over a range of time scales in systems of natural variability (Glacial to Interglacial, Holocene) and in human perturbed systems (industrial era) Integrate proxy records with present day observations (link to WP3) Improve understanding of proxy incorporation during calcification (link to WP4)

3. Objectives Evaluate the response of calcifying organisms to past changes in ocean acidification Assess the role of carbonate dissolution in the natural carbonate chemistry of the ocean Advance the parameterization of climate and biogeochemical processes affected by ocean acidification in model predictions (link to WP10, WP12)

4. Determination of the evolution of oceanic carbonate chemistry over a range of time scales in systems of natural variability and in human perturbed systems

5. Determination of the evolution of oceanic carbonate chemistry over a range of time scales in systems of natural variability and in human perturbed systems Rapid Events Glacial-interglacial changes in ocean carbonate system Records of the industrial age

6. Work and participants • Analyses of foraminifera and coccoliths (geochemistry, isotopes, morphometry) from marine sediment cores for paleo reconstruction Cambridge, Bergen, Amsterdam, CEREGE, AWI, Bern • Analyses of foraminifera and coccoliths from core-tops, sediment traps and water column samples for integration of proxy and present day records Cambridge, Bergen, Amsterdam, CEREGE, AWI, Bern • Analyses of cold water corals: field calibration and geochemistry LSCE

7. Work and participants • Determination of the dissolution kinetics of biogenic carbonates Brussels • Model simulation (including a sediment module) of Glacial to Interglacial rain ratio and carbonate compensation response Bergen, Bern,Bristol • Model simulation of Cretaceous/Paleogene acidification event LSCE,Southampton,Bristol

8. System where atmospheric CO2 defined by ocean-atmosphere interactions with internal and external carbon reservoirs System where atmospheric CO2 change shows response in oceans

9. “Paleo-analogs”

10. There are no good analogs for the perturbations we are making. The world has never before seen such a rapid rise in greenhouse gases with the present-day configuration of the continents and with large amounts of polar ice. The simplest use of the paleo record - just going back to a point that had similar conditions to what we expect for the future - doesn't work very well because because there are no good analogs for the perturbations we are making. So more sophisticated approaches must be developed. Exception is Records of the Industrial Age

11. Records of the industrial age Challenge: Obtain marine records that define seawater carbonate chemistry Investigate whether/to what extent records modified by increase in anthropogenic CO2

12. Archives Corals Rapidly-accumulating sediment cores Core tops Water column samples (trap, tow) Experimental systems (lab and field)

13. Tools Foraminifer shell weight Coccolith mass Shell chemistry (13C, 11B, Sr/Ca, B/Ca….) Calibrate/improve with links to other WPs Examples from EPOCA proposal…..

14. Planktonic foraminifer G. Bulloides normalised shell mass and glacial-interglacial [CO32-] Barker & Elderfield (2002)

15. B/Ca- [CO32-] in benthic foraminifera and [CO32-] reconstruction of N. Atlantic glacial water column Yu and Elderfield (2007)

16. Records of the industrial age from North Atlantic

17. Records of the industrial age from North Atlantic RAPID core-21-12B southern Gardar Drift 57o 27.09’N 27o 54.53’W 2630m water depth Boessenkool et al (2006) Iglesias Rodriguez et al (2008) Elderfield et al unpublished data

18. Records of the industrial age from North Atlantic Core HM01-128-04 Ormen Lange 63o 45.8’N 05o 15.3’E 845.4m water depth Carin Andersson Dahl (Berknes Centre, Bergen) unpublished data

19. Records of the industrial age from North Atlantic Core HM01-128-04 Ormen Lange 63o 45.8’N 05o 15.3’E 845.4m water depth Carin Andersson Dahl (Berknes Centre, Bergen) unpublished data

20. Ormen Lange cores HM01-128-04 and P1-003MC 210Pb dating method Sedimentation rate = 1.3 to 2.2 mm a-1 0.5 cm intervals ≈ 2.3 to 3.8 years 1865-2000 AD Andersson Dahl

21. Gardar Drift core RAPID-21-12B 210Pb dating method Linear sedimentation rate = 2.3 ± 0.2 mm a-1 Sampled at 0.5 cm intervals ≈ 2.2 ± 0.2 years 1770-2004 AD Boessenkool et al (2006)

22. No long term trend in coccolithophore species composition Iglesias Rodriguez et al (2008)

23. 40 % increase in average coccolith mass since ca 1950 Iglesias Rodriguez et al (2008)

24. Shell weight of G.bulloides in 250-350µm 12 % decrease in planktonic foraminifera mass since ca 1900

25. increase in average coccolith mass decrease in planktonic foraminifera mass

26. decrease in G bulloides Sr/Ca related to calcification rate - [CO32-] - inorganic calcite

27. Lessons from the past Shell weight and Sr/Ca can vary for other reasons

28. G. Bulloides shell weight and 18O in Southern Ocean Low shell weight at interglacial (high CO2) times Greaves et al (2008)

29. Benthic foraminiferal Sr/Ca and 18O in Southern Ocean

30. An idea for paleo rain ratio Late Glacial Maximum carbonate saturation in the North Atlantic Ocean and rain ratio

32. Conclusions Industrial age records a challenge but very important EPOCA must enable integration of modern observational studies with paleo records Combination of 1 and 2 potential to make a very significant contribution to understanding of effects of ocean acidification Records of Glacial-Interglacial periods and rapid events also relevant