1. CLIMATE MODEL SIMULATES GLOBAL COLD CLIMATE DURING LATE MAUNDER MINIMUM (1675-1710) Hans von Storch, Fidel González-Ruoco, Ulrich Cubasch, Jürg Luterbacher, Eduardo Zorita, Beate Müller, Stephanie Legutke, and Ulrich Schlese Visit to JISAO, Seattle, 30. October 2003

2. Simulation with ECHO-G (ECHAM4/HOPE-G) for - 500 years (Columbus-run), and - 1000 years (Erik run) forced with - variable solar output - Volcanic aerosol load - GHG concentrations

5. Eduardo Zorita, pers. comm. Yegor Dimitriev, pers. comm.

6. LMM11671-1684 NAO- and Cooling LMM21685-1708 NAO+ and Warming Irene Fischer-Bruns, pers. comm.

7. Late Maunder Minimum Cold winters and springs, 1675-1710 Late Maunder Minimum Cold winters and springs, 1675-1710 Analysis of Columbus run, only.

8. Baltic Sea ice winter index after Koslowski (1998) grey: Index, red: 5 year mean, blue:20 year mean

9. The Late Maunder Minimum (LMM) is the coldest phase of the so-called ‘Little Ice Age’ with marked climatic variability over wide parts of Europe. Temperature conditions in Switzerland according to Pfister‘s (1999) classification. 1675-1710 vs. 1550-1800 Reconstruction from historical evidence, from Luterbacher et al.

10. Mean winter temperatures in Tallin as reconstructed by Tarand & Nordli, 2001

11. 1675-1710 vs. 1550-1800 Reconstruction from historical evidence, from Luterbacher et al. Late Maunder Minimum Model-based reconstuction

12. LMM – reference period, winter Beate Müller, pers. comm. Erik Columbus Eduardo Zorita, pers. comm.

13. Simulated global 1675-1710 temperature anomaly

14. Ice Cores From Greenland and Antarctica Stacked isotope record from five North-Greenland ice cores (Schwager, 2000) Stacked isotope record from three ice cores from Dronning Maud Land, Antarctica (Graf et al., in press ) Reconstruction of solar variability, deduced from 10 Be measurements (Crowley, 2000) Antarctica North Greenland

16. Corals off Madagaskar The empirically reconstructed 338 year record of variations in sea-surface temperatures as inferred from the 1982-95 annual mean  18 O -SST calibration equations using SST observations from different sources. (From Jens Zinke)

17.  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 SST’s of about 0.5K Zinke, pers. communication

18. deMenocal et al. (2000)

19. Simulated differences of ice coverage, in percent, during the LMM event 1675-1710 and the long term mean 1550-1800.

20. Information provided by Fidel González-Rouco and Simon Tett HadCM3 ECHO-G differences relative to the 1550-1800 average; 25-year running averages.

21. gridding: Spatial: 0.5° x 0.5° Temporal: 6 h REMO Model Area ECHO-G gridding Dynamical downscaling

22. reconstructed data - REMOreconstructed data - ECHO Differences Temperatures in January

23. Differences Temperatures in July reconstructed data - REMOreconstructed data - ECHO

24. REMO und Luterbacher Seasonal temperature anomalies in areas with skill of reconstruction > 0.5 Winter Herbst Frühling Sommer

25. Temperaturanomalie des LMM für Zentral-England Winter

26. Winterliche Mitteltemperatur und Anomalie des LMM für den Tallinner Hafen Mittel

27. Conclusions AOGCM ECHO-G has been integrated with natural forcing (estimates) related to solar output and volcanic aerosols and anthropogenic GHG forcing over several hundred years (Columbus: 450 yrs, Erik the Red: 1000 yrs). Both simulations generate a globally cooler Northern winter Earth, 1400-1800, consistent with the concept of LIA. The cooling is considerably larger than described by Mann et al. The 1000 yrs Erik- simulation generates a medieval warm time. Both simulations simulate a marked global (north of 30°S) cooling during the Late Maunder Minimum. (Also: Dalton Minimum). The extra cooling amounts to 0.2-0.5K. Model simulations consistent with a number of proxy data, in Europe, and across the globe (corals, ice cores). Model simulates a significant ice anomaly in the Labrador Sea and adjacent seas during the LMM. NAO not uniform during LMM.