On the Dependence of the Solar Wind Velocity on the Fractional Area of Coronal Holes in Longitude

Abstract

The relationship between the fractional area of coronal holes and the maximum velocity of the fast solar wind at 1 AU based on AIA/SDO and ACE/SWEPAM observations is considered for the period from June 2015 to March 2017. Assuming the ballistic model of the solar wind propagation it has been shown that the coronal holes within the meridional slice ±10° make a basic contribution to the ecliptic solar wind. The maximum correlation coefficient between the area of coronal holes and the peak solar wind velocity at latitudes within ±40° was found to be equal to 0.762 ± 0.145. The probable causes of the discrepancy between the predicted and observed values of the solar wind velocity are discussed.