A new criterion for determining the time of a solar minimum

Abstract

We propose a minimum level of the smoothed values for the solar constant during a period of low sunspot activity as a new additional criterion for determining the time of a minimum between solar cycles. An indicator for the time of a minimum between cycles is the time at which a minimum level in the average monthly values of the integral flux of solar radiation smoothed over thirteen months (when the last four values of the flux are greater than the previous minimum point) is achieved. We successfully tested the new criterion to determine the time of the previous minima between cycles 21 and 22, 22 and 23, and 23 and 24.