The lack of solar wind monitoring just upstream of the Jovian magnetosphere makes such analysis problematic. The purpose of this study is to elucidate the fundamental response of the Jovian magnetotail to solar wind dynamic pressure enhancements. Their results are consistent with the concept of conservation of angular momentum, which supports the theory of Southwood and Kivelson and Cowley et al. showed that increases and decreases of the solar wind dynamic pressure changed the configuration of magnetic field in the Jovian magnetosphere. showed an event in which interplanetary shocks could trigger increases in both hectometric radio emission and extreme ultraviolet auroral emission. Recently, when the Cassini spacecraft was available as an upstream solar wind monitor, Gurnett et al. showed that the Pioneer 10 and 11 spacecraft made several crossings of the magnetopause at varying distances of 50–100 R J, corresponding to solar wind dynamic pressure enhancements. One of the most fundamental approaches in diagnosing the electromagnetic properties of magnetosphere is to investigate its response to an enhancement of the solar wind dynamic pressure. From Voyager 2 data, obtained at 18–32 R J, the magnetic field disturbances were interpreted as a Kolmogorov-type turbulence because the power spectral density decreases with frequency by a power law index of −5/3. Magnetic field disturbances in the mHz band are observed simultaneously with the rectangular waveforms. This modeled current sheet lies in the magnetic dipole equator at 15–30 R J, where R J is the radius of Jupiter, and becomes parallel to the Jupiter's rotational equator at >60 R J. Khurana derived a current sheet model from the magnetic field data obtained by Voyager 2. This waveform is the result of a current sheet crossing caused by the tilt of the Jovian dipole moment to the spin axis. The most prominent perturbation is a rectangular magnetic field waveform with a 10-hour period. In the Jovian magnetosphere, the magnetic field has been observed by the Pioneer 10 and 11, Voyager 1 and 2, Ulysses, Galileo, and Cassini missions. Magnetic field measurements have been the most important and fundamental technique required for the investigation of the electromagnetic environment of planetary magnetospheres since the beginning of space research. We suggest that the current sheet is greatly deformed and reconnection bursts are induced under the compressed magnetosphere. The maximum amplitude of the disturbances is in proportional to the maximum amplitude of the solar wind dynamic pressure. Magnetic field disturbances in the frequency range from 0.3 to 10 mHz are enhanced simultaneously. The rectangular waveform due to the Jovian rotation disappears for eight of the nine events. Characteristic magnetic field variations are found in the Jovian magnetosphere for all of the nine events. We identify the events with an increase of the solar wind dynamic pressure >0.25 nPa at the Jovian orbit. The lack of solar wind monitoring just upstream of the Jovian magnetosphere is overcome by simulating a one-dimensional magnetohydrodynamic (MHD) propagation of the solar wind from the Earth. In order to understand the response of the Jovian magnetosphere to solar wind dynamic pressure enhancements, we investigate magnetic field variations observed by the Galileo spacecraft.
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