Fig. 5

a Horizontal component of geomagnetic disturbances ΔH at Colaba; b, c estimated geoelectric disturbances E_x and E_y at Kakioka; d calculated GIC at SFS; e calculated GIC at STB, and f calculated GIC at SFJ. The vertical bars indicate the values that were obtained when we applied ± 0.9ΔH/2 to ΔD in Eq. (5)