We have performed the analysis of the temporal variations of the X, Y, Z geomagnetic field components recorded at 9 stations of the INTERMAGNET network during the Great North American Eclipse of April 8, 2024, as well as during quiet time reference period. It has been shown that the solar eclipse (SE) was accompanied by both up to a 10 nT decrease in the strength of all geomagnetic field components, and up to a 10 nT increase of in the strength of individual components at a number of stations. The durations of the disturbances in all components were close in value, and they usually ranged from 120 to 200 min, whereas the SEs took place within a 130 to 135 min interval. The delay or advance time of the geomagnetic effect depended on the geometry of the Moon’s shadow. The SE was accompanied by suppression of an oscillation with a period of about 60 min and amplitude of 1–3 nT, which existed prior to the eclipse. A tendency was observed for the geomagnetic effect to increase as the SE magnitude increased. The magnitude of the SE geomagnetic effect has been confirmed to depend not only on the eclipse magnitude, but also on the location of the magnetometer station, the geometry of the Moon’s shadow, the state of the ionosphere and the patterns of ionospheric currents. The estimates of the geomagnetic effect are in good agreement with the observational data.
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