Simulations, Observations & Palæoclimatic data: climate variability over the last 500 years ECHAM4/HOPE-G = ECHO-G runs, forcings, results so far Hans von Storch Institute for Coastal Research, GKSS Research Centre, Geesthacht, Germany SO&P startup meeting, Norwich, January 2003

List of simulations ECHO-G f77 Control run, 1990 conditions, 1000 year long Forced run, , 12-h output “Christof Columbus” Forced run: , 12-h output Forced run: , 6-h output ECHO-G f90 Remo Control run, 1990 conditions, 400 years long Control run, 1850 conditions, 1000 years long Forced run, , 12-h output ongoing) “Erik the Red” Control run, 1610 conditions, 50 years long Forced run, , 6-h output

Planed simulations ECHO-G f90 A second Forced simulation Depending on differences between both forced simulations f77 f90 Forced simulation , no volcanoes Forced simulation , no solar variability Forced simulation , no greenhouse gas variability Planed simulations REMO Medieval Optimum, Europe

Model used is ECHO-G, a community model provided by Max Planck Institute for Meteorology, maintained by Model & Data at MPI for Meteorology in Hamburg The runs are made and evaluated in a consortium: a)Institute for Coastal Research, GKSS b)Meteorological Department, Free University Berlin c)Model & Data, MPI for Meteorology, Hamburg d)Department for Meteorology and Climatology, U Complutense, Madrid and Universities in Lecce (Italy), Nanjing (China). Comparison with historical and geological data are made together with a)„KIHZ partners“ (Alfred Wegener I, Bremerhaven; Geoforschungszentrum, Potsdam; FZ Jülich, and others) b)U Bern, Switzerland

Variations in the effective solar constant including variations in solar irradiance and volcanic aerosols (Crowley, 2000) Estimated changes in CO2 (Etheridge et al., 1996) Estimated changes in methane CH4

More actual data via internetinternet

Temperature Responses Tett, pers. comm.

(a) NAOI in the forced climate simulation, simulated by the ECHO-G model, and reconstructed from the simulated air- temperature field and the precipitation field in the North Atlantic sector over land grid points. (b) As (a) with a 50-year gaussian filter. (c) NAOI as in (b) but in the control simulation. Zorita and González-Rouco, 2002

control forced

Institut für Küstenforschung I f K

Late Maunder Minimum Cold winters and springs, Late Maunder Minimum Cold winters and springs,

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 classification. From Luterbacher, vs Reconstruction from historical evidence, from Luterbacher et al.

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

Lake Sediments From Lake Holzmaar magnetic susceptibility = clastic input?  13 C + Aulacoseira subarctica Reduced growing season? Dryer winters?

vs Reconstruction from historical evidence, from Luterbacher et al. Late Maunder Minimum Model-based reconstuction

Institut für Küstenforschung I f K Global temperature anomaly Model as a constructive tool

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

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 , with annual resolution. The intervals , and were found warmer than “normal”, whereas the intervals , (LMM) and cooler than on average.  18 O increases of about ‰ heavier during LMM than between and is indicative for a cooling of K.  New Caledonia (SW-Pacific, 22 o S, 166 o E, Quinn et al., 1998): 335 years of coral  18 O records from , with seasonal resolution. The records describe a brief interval of modest cooling in the late 17th century, with an annual mean SST about K cooler between than between and  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 , 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

Marine Sediments Off Peru Indicator for bio-productivity and intensity of upwelling in the ocean off Peru. The indicator is derived from characteristics in the marine sediment. Higher values are associated with stronger upwelling and lower values with reduced upwelling. deMenocal et al. (2000)

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

LMM NAO- and Cooling LMM NAO+ and Warming Irene Fischer-Bruns, pers. comm.

Simulated differences of ice coverage, in percent, during the LMM event and the long term mean Institut für Küstenforschung I f K Model as a constructive tool

Resolution: T30 6 hourly Forcing data from ECHO-G (special run Late Maunder Minimum) Beate Müller, pers. comm.

Resolution: spatial 0.5° x 0.5° temporal 6 h Model Area Beate Müller, pers. comm.

Regionalized sea ice data Main land use types in Germany from 7th century area [%] Beate Müller, pers. comm.

Differences reconstructed data - REMOreconstructed data - ECHO January Beate Müller, pers. comm.

Differences reconstructed data - REMOreconstructed data - ECHO July Beate Müller, pers. comm.

Differences of 30-year monthly means Differences of 30-year monthly means LMM(6h)** - ”Normal Period“ (12h)* Month LMM-NP * ** Beate Müller, pers. comm.

Iberian peninsula Winter Summer ECHO-G REMO Luterbacher Beate Müller, pers. comm.

DJF-Mean Temperatures of De BiltCentral England ECHO-G REMO Luterbacher Luterbacher /Manley Beate Müller, pers. comm.