Possible Influences of Volcanic Dust Veils or Changes in Solar Luminosity on Long-term Local Temperature Records

Abstract

Two external forcing functions are examined in their relationship to temperature records at individual locations. Postulated changes in solar luminosity, deduced from sunspot structure, and the dust veil hypothesis are separately considered as possible linear forcings of surface temperature. Changes in solar luminosity appear to give a marginally better correlation with temperature records than the dust veil hypothesis, but each hypothesis alone only amounts for ?2% of the year-to-year variance at individual locations on the average. The hypothesis of linear external forcing of temperature appears to be a better hypothesis for the continental interiors than for the oceans. Although both hypotheses have been used to successfully explain many of the observed features of variations in the average Northern Hemisphere surface temperatures, such knowledge does not greatly aid in the explanation of temperature variations on the local scale.