Variations in the Sun’s Meridional Flow over a Solar Cycle

Abstract

Solar Meridional Flow: The surface of the Sun is composed of plasma that exhibits observable flow patterns. The weakest flow pattern occurs along meridional lines from the equator toward the poles. Hathaway and Rightmire (p. 1350 ) measured the meridional flow using observations taken with the Michelson Doppler Imager onboard the Solar and Heliospheric Observatory between 1996 and 2009 and found that meridional flow varied with the solar cycle, such that flow was faster during the 2004–2009 minimum than during the 1996–1997 minimum. This finding provides further evidence that the last solar minimum was peculiar by comparison with previous cycles.