Fig. 10From: Solar flare effects on D-region ionosphere using VLF measurements during low- and high-solar activity phases of solar cycle 24ΔH′ versus flare power for the two signal paths during periods of low and moderate solar activity. ΔH′ = H′ − H′ p , where H′ is the quiescent-level ionospheric reflection height and H′ p is the reflection height during the solar flare peakBack to article page