Solar Influence on Surface Air Temperature During the Maunder Minimum

 

Authors:          Joan Feynman (1), Alexander Ruzmaikin (1), Xun Jiang (2), David Noone (2), and Yuk Yung (2)

Affiliations:     1) Jet Propulsion Laboratory, California Institute of Technology

                        2) Dept. of Geology & Planetary Sciences, California Institute of Technology

 

The Northern Annular Mode (NAM) of the wintertime atmospheric variability in the troposphere has been shown to be influenced by changes in the solar UV radiation (Ruzmaikin and Feynman, 2002, JGR, 107, D14) suggesting that a mechanism of solar influence on climate involves the modulation of this mode.  In the past 50 years the monthly averaged NAM index has been lower at solar minima than at solar maxima. Using this result and the solar UV irradiance extrapolation by Lean et al. (Global Biogeochem. Cycles, 9, 171, 1995) we evaluate the difference in the NAM index at current minima and the Maunder Minimum (1645-1715).  This allows us to infer the temperature anomalies during the Maunder Minimum in winter months.  A major effect of the temperature changes Northern Hemisphere during the Maunder Minimum can be attributed to effect of solar UV on the NAM.  The temperature patterns are compared with those empirically reconstructed by Mann et al., (1998). We find the expected cooling in the Northern Europe and Siberia, and also a strong warming at the Labrador Sea. This pattern is in remarkable agreement with the pattern of correlations between empirically determined sensitivity of empirically derived surface temperatures to solar irradiance variations (Waple et al., Climate Dyn., 18, 563, 2002).