The passage of the transmitted shock causes the bow shock and magnetopause to move inward, while the passage of the reflected fast shock causes these boundaries to move outward, consistent with previously reported in situ observations. The reflected fast shock propagates sunward through the dayside magnetosphere and magnetosheath. The model predicts the propagation of a transmitted fast shock through the magnetosheath and magnetosphere and the reflection of this shock from the inner numerical boundary. The global BATS-R-US MHD code is used to simulate the interaction of a moderately strong interplanetary shock with the Earth's magnetosphere. We conclude, that the OMNI data base is good for TDs and can not be used for FSs. As for normals, the average angle between normals from OMNI and our normals is 13 degrees for TDs and 66 degrees for FSs. For shocks OMNI gives unrealistic results: on average the Pd jumps come to the bow shock 4 min after the ground SIs. Thus the OMNI procedure is better than the convection one. For convection translation the average delays are also 4 min, but the scatter is larger. The results are as follows: According to OMNI, TDs come to the bow shock on average 4 min before SIs on the ground. 62 SYM jumps, corresponding to 35 TDs and 27 FSs, were analyzed. Two types of discontinuities corresponding to Pd jumps: tangential (TD), and fast shocks (FS) were considered.We also compare normals from OMNI and those obtained by methods for concrete discontinuities. We also transfer solar wind structures using methods of normal and velocity calculations for given type of discontinuities. We study the response time of the ground SYM-index to solar wind dynamic pressure (Pd) jumps, recorded by remote (100-200Re) spacecraft and transferred to Earth bow shock(BS) according to OMNI and by convection time. The model uses the 81-day average value of the F10.7 solar flux, 20 months prior to the given date, to track changes in the ring current base line with solar cycle progression (F10.7 default value is 120.0).The purpose of our work is to test the OMNI data base() on interplanetary discontinuities, using ground observations. A default value of 0.5 mV/m is to be used if the value of Em is not known. The merging electric field Em is a parameter derived from the solar wind measurements by: Em (in mV/m) = V * BT * sin(beta/2.0) * sin(beta/2.0) / 1000, where V is the solar wind flow speed in km/s, BT is the strength of the interplanetary magnetic field perpendicular to the Sun-Earth axis and beta is the clock angle acos(Bz/BT). The Interplanetary magnetic field and F10.7 index are available from OMNIWEB (default IMF-BY = 0.0). The magnetospheric ring current is tracked by Est/Ist (the default values for Est and Ist are both 0.0). The model is more accurate if the present state of the magnetosphere is provided as an input in the form of magnetic indices. It has the same parametrization of the magnetospheric field as POMME-6 and POMME-7. Pomme-8 was produced from CHAMP satellite vector magnetic measurements from July 2000 up to September 2010 and Oersted satellite total field measurements from January 2010 to January 2013. The time variations of the internal field are given by a piece-wise linear representation of the spherical harmonic (Gauss) coefficients of the magnetic potential. POMME is a scientific main field model representing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers.
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