1. Simulation of the Late Maunder Minimum ? Hans von Storch Institute of Coastal Research, GKSS Research Centre Geesthacht, Germany København, 17. Oktober 2001 Simulation of the Late Maunder Minimum ? Hans von Storch Institute of Coastal Research, GKSS Research Centre Geesthacht, Germany København, 17. Oktober 2001 Institut für Küstenforschung I f K Joint work of Fidel Gonzalez-Rouco, Ulrich Cubasch, Stefanie Legutke, Jürg Luterbacher, Ulrich Schlese, Hans von Storch, Eduardo Zorita Joint work of Fidel Gonzalez-Rouco, Ulrich Cubasch, Stefanie Legutke, Jürg Luterbacher, Ulrich Schlese, Hans von Storch, Eduardo Zorita

2. 1450-2000 simulation Changing solar forcing and time variable volcanic load; greenhouse gases Spin-up 1450-1550 Forced Simulation Institut für Küstenforschung I f K

3. Late Maunder Minimum Cold winters and springs, 1675-1710 Late Maunder Minimum Cold winters and springs, 1675-1710

4. Institut für Küstenforschung I f K Temperature conditions in Switzerland according to Pfisters classification. From Luterbacher, 2001

5. Climate model used Atmosphere: ECHAM4 horizontal resolution T30 ~ 300 km at mid latitudes Ocean: HOPE-G horizontal resolution T42 ~ 200 km at mid latitudes increased resolution in the tropics Model provided as community climate by Model & Data Group at MPI for Meteorology and run at German Climate Computing Centre (DKRZ) and computing facilities at FZ Jülich Institut für Küstenforschung I f K

6. effective solar output methane (ppb) CO 2 (ppm)

7. control forced

8. 1675-1710 vs. 1550-1800 Reconstruction from historical evidence, from Luterbacher et al. Model-based reconstuction Late Maunder Minimum validation

9. Institut für Küstenforschung I f K Air pressure difference, 1675-1710 vs. 1550-1800 hPa H H L Model as a constructive tool

10. Institut für Küstenforschung I f K Global 1675-1710 temperature anomaly Model as a constructive tool

11. Institut für Küstenforschung I f K Coral-estimated SST for a location off Madagaskar Zinke, pers. communication validation

12. Institut für Küstenforschung I f K Zinke, pers. communication

13. Institut für Küstenforschung I f K Galapagos (E-Pacific, 1 o S, 90 o W, Dunbar et al., 1994): 367 years of coral 18 O records from 1587-1953, with annual resolution. The intervals 1660-80, 1710-1800 and 1870-95 were found warmer than normal, whereas the intervals 1600-1660, 1680-1700 (LMM) and 1800-25 cooler than on average. 18 O increases of about 0.1-0.15 heavier during LMM than between 1660-70 and 1705-50 is indicative for a cooling of 0.5- 0.75K. New Caledonia (SW-Pacific, 22 o S, 166 o E, Quinn et al., 1998): 335 years of coral 18 O records from 1657-1952, with seasonal resolution. The records describe a brief interval of modest cooling in the late 17th century, with an annual mean SST about 0.2-0.3K cooler between 1680-1740 than between 1660-80 and 1740-50 Great Barrier Reef, Abraham Reef (SW-Pacific, 22 o S, 153 o E, Druffel and Griffin, 1993): 323 years of coral 18 O records from 1635-1957, with bi-annual resolution. More positive 18 O values (ca. 0.1) during the LMM, are consistent with lower SSTs of about 0.5K Zinke, pers. communication

14. Institut für Küstenforschung I f K Hubertus Fischer, 1998 cold warm

15. Institut für Küstenforschung I f K

16. D'Arrigo and Jacoby. Reconstructed mean annual temperatures for northern North America Institut für Küstenforschung I f K CLIMATE SINCE A.D. 1500, Edited by Raymond S. Bradley and Philip D. Jones, Routledge, London, 1992 (679pp)

17. Simulated differences of ice coverage, in percent, during the LMM event 1675-1710 and the long term mean 1550-1800. Institut für Küstenforschung I f K Model as a constructive tool

18. Institut für Küstenforschung I f K

19. Conclusions 1675-1715 LMM was a significant winter climate anomaly well documented in Europe coincident with solar anomalies Similar winter anomalies simulated in 1550-2000 AOGCM, forced transiently with anomalous solar output and volcanic aerosol load In the model, the LMM appears as global phenomenon with maxium effects on the Northern Hemisphere in particular in the Labrador Sea Anomaly results of dynamical interplay of atmosphere and ocean Anomaly reminiscent of Great Salt Anomaly 1675-1715 LMM was a significant winter climate anomaly well documented in Europe coincident with solar anomalies Similar winter anomalies simulated in 1550-2000 AOGCM, forced transiently with anomalous solar output and volcanic aerosol load In the model, the LMM appears as global phenomenon with maxium effects on the Northern Hemisphere in particular in the Labrador Sea Anomaly results of dynamical interplay of atmosphere and ocean Anomaly reminiscent of Great Salt Anomaly

20. Institut für Küstenforschung I f K

21. Institut für Küstenforschung I f K LMM? Dalton?