Patterns of tropospheric response to solar variability

Abstract

Despite numerous reports of apparent climate responses to the 11-year solar cycle, the Sun's role for weather and climate has remained a matter of controversy. One important reason is the difficulty of reliably attributing the observed atmospheric effects to solar variability, rather than to other forcing factors or intrinsic variability. Here we show that consistent patterns of statistically significant solar signals emerge in all major observables throughout the low- and mid-latitude troposphere, when El Niño and volcanic signals are removed from meteorological data. Solar forcing is strongest in the tropics and at mid-latitudes, and the heating and moistening of the troposphere during solar maximum is accompanied by a modulation of the large-scale tropospheric circulation systems. These findings have implications for the question of where and how the Sun exerts its influences in the climate system.