Fig. 1
From: Modulation of the ionosphere by Pc5 waves observed simultaneously by GPS/TEC and EISCAT
Pierce points at 250 km altitude of radio paths from GPS satellites GPS7, GPS9, and GPS28 to ground receivers KIRU (violet line), VARS (orange line), and TROM (green line) in Scandinavia during October 31, 2003, 1100–1130 UT. Magnetometers are denoted with triangles, GPS receivers are denoted with squares, riomer KIL is marked with asterisk, and EISCAT is shown by dark circle