SOLAR-TERRESTRIAL RELATIONS: PREDICTING THE EFFECTS ON THE NEAR- EARTH ENVIRONMENT, cilt.22, sa.1, ss.139-142, 1998 (SCI-Expanded)
For solar cycle 21 (1976 - 1986) the variation of monthly mean values of noon-time foF2 at Slough, Rome, and Manila are examined by using solar flare index and geomagnetic Ap index. A single regression analysis for dependence of foF2 on solar flare index shows better matching: Moreover, less hysteresis effect is seen when we use solar flare index instead of other solar indices. Thus, for making prediction, one needs to take into account just the solar flare index and not the solar flare index and geomagnetic Ap index simultaneously. (C) 1998 COSPAR, Published by Elsevier Science Ltd. All rights reserved.