analyze the consistency of the coupled atmosphere-ocean GISS-ER climate model
in reproducing South American temperature anomalies over the last millennium.
For that purpose, we compare the model results with the Neukom’s temperature
anomaly reconstruction provided by a statistical model that uses multiproxy
data and climatological temperature anomalies. Specifically, we examine
temperature anomalies for summer and winter of a 6-member ensemble of the
GISS-ER model with 1× solar forcing and 2× solar forcing, calculated for the
period 1000-1899. Using the Neukom’s reconstructions and the model outputs, we
calculate the summer mean anomalies of the period 1001-1700 (a period that
includes Medieval Climate Anomaly -MCA- and Little Ice Age -LIA-), and winter
mean anomalies of the period 1706-1800 (a period that includes the
pre-industrial period). These mean anomalies are subtracted from Neukom’s
reconstructions defining the reconstructions wrt 1001-1700 (summer) and wrt
1706-1800 (summer and winter). In general, the model is not very consistent
with the reconstructions, since the model’s mean and spread show very small
interannual variability in contrast to what the reconstructions exhibit, and
often with anomalies of opposite sign. In the period 1001-1700, the model
presents, on average, negative temperature anomalies for the 1× and 2× forcing.
In the period 1706-1800, the model displays positive anomalies for summer and
negative anomalies for winter for the 1× and 2× forcing. In particular, the
anomaly that better reproduces the sign of the reconstructions is that wrt
1001-1700 with 1× forcing and for summer. The model has an error of only 33% in
reproducing the sign of the anomalies, in comparison to the Neukom’s
reconstruction for the same reference period. The model’s anomaly wrt 1001-1700
with 1× forcing for summer also reproduces the MCA and LIA’s sign of the
reconstruction. The MCA’s sign is reproduced in almost 75% of the comparisons,
and the LIA’s sign in more than 73% of the comparisons with the reconstruction,
indicating that the model can represent this important anomalies.
 Mann, M.E., et al. (2009) Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly. Science, 326, 1256-1260.
 Mann, M.E., Bradley, R.S. and Huges, M.K. (1998) Global-Scale Temperature Patterns and Climate Forcing over the Past Six Centuries. Nature, 392, 779-787. http://dx.doi.org/10.1038/33859
 Mann, et al. (2008) Proxy-Based Reconstructions of Hemispheric and Global Surface Temperature Variations over the Past Two Millennia. PNAS, 105, 13252-13257. http://dx.doi.org/10.1073/pnas.0805721105
 Jones, P.D., Osborn, T.J. and Brifa, K.R. (2001) The Evolution of Climate over the Last Millennium. Science, Paleoclimate Review, 292, 662-667.
 Briffa, K.R., et al. (1998) Influence of Volcanic Eruptions on Northern Hemisphere Summer Temperature over the Past 600 Years. Nature, 393, 450-455. http://dx.doi.org/10.1038/30943
 Briffa, K.R., et al. (2008) Trends in Recent Temperature and Radial Tree Growth Spanning 2000 Years across Northwest Eurasia. Philosophical Transactions of the Royal Society B, 363, 2271-2284.http://dx.doi.org/10.1098/rstb.2007.2199
 Cobb, et al. (2003) El Nino/Southern Oscillation and Tropical Pacific Climate during the Last Millennium. Nature, 424, 271-276. http://dx.doi.org/10.1038/nature01779
 Mann, M.E. and Jones, P.D. (2003) Global Surface Temperatures over the Past Two Millennia. Geophysical Research Letters, 30, 1820-1824. http://dx.doi.org/10.1029/2003GL017814
 Luterbacher, et al. (2004) European Seasonal and Annual Temperature Variability, Trends, and Extremes since 1500. Science, 303, 1499-1503. http://dx.doi.org/10.1126/science.1093877
 Trouet, V., et al. (2009) Persistent Positive North Atlantic Oscillation Mode Dominated the Medieval Climate Anomaly. Science, 324, 78-80. http://dx.doi.org/10.1126/science.1166349
 Neukom, R., et al. (2010) Multiproxy Summer and Winter Surface Air Temperature Field Reconstructions for Southern South America Covering the Past Centuries. Climate Dynamics, 37, 35-51.http://dx.doi.org/10.1007/s00382-010-0793-3
 Neukom, R. and Gergis, J. (2012) Southern Hemisphere High-Resolution Palaeoclimate Records of the Last 2000 Years; Southern Hemisphere High Resolution Palaeoclimate Records of the Past 2000 Years. The Holocene, 5, 501-524. http://dx.doi.org/10.1177/0959683611427335
 Neukom, R. and Luterbacher, J. (2011) Climate Variability in the Southern Hemisphere. Global Change, 76, 26-29.
 Smerdon, J.E., et al. (2011) Spatial Performance of Four Climate Field Reconstruction Methods Targeting the Common Era. Geophysical Research Letters, 38, Article ID: L11705.http://dx.doi.org/10.1029/2011GL047372
 Bauer, E., Claussen, M., Brovkin, V. and Huenerbein, A. (2003) Assessing Climate Forcings of the Earth System for the Past Millennium. Geophysical Research Letters, 30, 1276-1284. http://dx.doi.org/10.1029/2002GL016639
 Intergovernmental Panel on Climate Change (IPCC) (2007) Climate Change. Cambridge.
 Luterbacher, et al. (2011) Reconstructed and Simulated Medieval Climate Anomaly in Southern South America. PAGES News, 19, 20-21.
 Schmidt, G.A., et al. (2006) Present-Day Atmospheric Simulations Using GISS Model E: Comparison to in Situ, Satellite, and Reanalysis Data. Journal of Climate, 19, 153-192. http://dx.doi.org/10.1175/JCLI3612.1
 Sun, S. and Bleck, R. (2006) Multi-Century Simulations with the Coupled GISS-HYCOM Climate Model: Control Experiments. Climate Dynamics, 26, 407-428. http://dx.doi.org/10.1007/s00382-005-0091-7
 Shindell, D.T., et al. (2006) Simulations of Preindustrial, Present-Day, and 2100 Conditions in the NASA GISS Composition and Climate Model G-PUCCINI. Atmospheric Chemistry and Physics, 6, 4427-4459.http://dx.doi.org/10.5194/acp-6-4427-2006
 Shindell, D.T., et al. (2006) Solar and Anthropogenic Forcing of Tropical Hydrology. Geophysical Research Letters, 33, Article ID: L24706. http://dx.doi.org/10.1029/2006GL027468
 Schmidt, G.A., Hoffmann, G., Shindell, D.T. and Hu, Y. (2005) Modeling Atmospheric Stable Water Isotopes and the Potential for Constraining Cloud Processes and Stratosphere-Troposphere Water Exchange. Journal of Geophysical Research, 110, Article ID: 021314. http://dx.doi.org/10.1029/2005JD005790
 Lean, J.L., Wang, Y.-M. and Sheeley Jr., N.R. (2002) The Effect of Increasing Solar Activity on the Sun’s Total and Open Magnetic Flux during Multiple Cycles: Implications for Solar Forcing of Climate. Geophysical Research Letters, 29, 77-1-77-2.
 Bard, E., Raisbeck, G., Yiou, F. and Jouzel, J. (2007) Comment on “Solar Activity during the Last 1000 yr Inferred from Radionuclide Records” by Muscheler et al. (2007). Quaternary Science Reviews, 26, 2301-2304.http://dx.doi.org/10.1016/j.quascirev.2007.06.002
 Beckman, J.E. and Mahoney, T.J. (1998) The Maunder Minimum and Climate Change: Have Historical Records Aided Current Research? ASP Conference Series, 153, 212-217.