Forecasting F 10.7 with solar magnetic flux transport modeling

Abstract

A new method is presented here to forecast the solar 10.7cm (2.8GHz) radio flux, abbreviated F 10.7, utilizing advanced predictions of the global solar magnetic field generated by a flux transport model. Using indices derived from the absolute value of the solar magnetic field, we find good correlation between the observed photospheric magnetic activity and the observed F 10.7 values. Comparing magnetogram data observed within 6 hours of the F 10.7 measurements during the years 1993 through 2010, the Spearman correlation coefficient, r s, for an empirical model of F 10.7 is found to be 0.98. In addition, we find little change in the empirical model coefficients and correlations between the first and second 9year intervals of the 18year period investigated. By evolving solar magnetic synoptic maps forward 1-7days, this new method provides a realistic estimation of the Earth-side solar magnetic field distribution used to forecast F 10.7. Spearman correlation values of approximately 0.97, 0.95, and 0.93 are found for 1day, 3day, and 7day forecasts, respectively. The method presented here can be expanded to forecast other space weather parameters, e.g., total solar irradiance and extreme ultraviolet flux. In addition, near-term improvements to the F 10.7 forecasting method, e.g., including far-side magnetic data with solar magnetic flux transport, are discussed. Copyright 2012 by the American Geophysical Union.