Comparison of proxy records of climate change and solar forcing

The role of solar variability as a cause of decadalcentennial scale climate change continues to be a topic of debate. Herein we compare two estimates of solar variability since 1600 with two estimates of northern hemispheric temperature change. Sun-climate correlations vary between 0.57-0.74 and are significant at the 95% level. However, the small number of oscillations in the time series suggests to us that longer records are needed for a more convincing demonstration of a significant sun-climate linkage. Forcing of an energy balance model with the solar time series indicates that modest amounts of solar variability and climate sensitivity yield temperature variations that represent a significant fraction of the inferred changes during the Little Ice Age. This latter result further supports the hypothesis that solar variability may be significantly contributing to climate change on decadal-centennial time scales.