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Gonzalez, A. L. C.

Publications and source records attributed to Gonzalez, A. L. C..

Moderate Geomagnetic Storms: Interplanetary Origins and Coupling Functions (ISEE3 Data)

Geomagnetic storms are related to the ring current intensification, which is driven by energy injection primarily during energetic solar wind-magnetosphere coupling due to reconnection at the magnetopause. This work identified the interplanetary origins of moderate geomagnetic storms (-100nT is less or equal to Dst(sub peak) is less than or equal to -50 nT) and analyzed the coupling processes during the storm main phase at solar maximum (1978-1979).

Mendes, Odim, Jr.↗

Interplanetary Origin of Geomagnetic Activity in the Declining Phase of the Solar Cycle

Interplanetary magnetic field and plasma data are compared with ground-based geomagnetic Dst and AE indices to determine the causes of magnetic storms, substorms, and quiet during the descending phase of the solar cycle. The primary focus is on 1974 data characterized by the presence of two long-lasting corotating streams associated with coronal holes.

Space Physics Magnetic Storms Geomagnetics Solar C↗

Dual-peak solar cycle distribution of intense geomagnetic storms

This paper studies the features of the solar cycle distribution of intense storms (Dst) during cycles 20 and 21 (1965-1985). For these cycles, the distribution of intense storms (including moderate events for this time interval) in terms of Dst values below -50 nT, showed a dual-peak distribution, providing evidence for another enhancement of the intense storm distribution at the late ascending phase of the cycle. The origin of the dual-peak distribution of intense storms is associated with a similar dual-peak distribution obtained for large-amplitude and long-duration values of the negative Bz component of the IMF, computed for the interval 1970-1981.

Gonzalez, W. D.↗

Comment on 'Large-scale response of the magnetosphere to a southward turning of the interplanetary magnetic field' by J. A. Sauvaud et al.

A study by Sauvaud et al. (1987) on the overall magnetospheric response to a southward turning of the IMF on March 4, 1979 is discussed. Because the coupling function epsilon for the most intense substorm in their study did not show any appreciable intensification prior to the occurrence of the substorm, Sauvaud et al. concluded that the substorm was driven by a magnetospheric reservoir. It is suggested that the coupling function epsilon does not necessarily well represent the magnetospheric energization due to possible combinations of solar wind parameters that are expected to influence the coupling. Therefore, it is concluded that the main substorm studied by Sauvaud et al. was probably driven by the solar wind.

Gonzalez, W. D.↗