Physics of auroral phenomena : proceedings of the 40th annual seminar, Apatity, 13-17 March, 2017 / [ed. board: N. V. Semenova, A. G. Yahnin]. - Апатиты : Издательство Кольского научного центра РАН, 2017. - 143 с. : ил., табл.

Comparison o fthe ionospheric effects o fthe space weather and seismogenic disturbances -60 -50 -40 30 -20 -10 о ю 20 зо GIM -TEC and UAM-T TEC disturbances on 01 /0 1 /2 0 1 6 , % iO:(K»UT 12:00 UT 14:00 UT 0 -30 30 30 0 -30 135' 180' b Figure 1. GPS observed and UAM-T calculated TEC disturbances (%) relative to the background values in the geomagnetic coordinates at 10:00 (leftpanels), 12:00 ( center) and 14:00 IJT (right) on January 1,2016: a) GIM-TEC, b) UAM calculated without currents, c) UAM calculated with j s= 20 nA/m2. Black line denotes the terminator, black star and diamond represent the earthquake epicenter and magnetically conjugated point, respectively. -175-150-125-100 -75 -50 -25 о 25 U AM -T Eastward drift velocity - Ж 1' L"—i at 300 km on 01 /0 1 /2 0 1 6, m /s 10:00 UT 12:00 UT 14:00UT a b Figure 2. The UAM calculated eastward drift velocity (m/s) distributions at 300 km: a) without seismogenic currents; b) j s= 20 nA/m2. Thus, the TEC disturbances caused by the upward seismogenic currents have a negative sign. Similar regions are clear visible in the GPS data. The presence of seismogenic currents leads to the increase o f the upward electric field and corresponding westward electromagnetic drift of the ionospheric F2-layer plasma. This drift forms the negative TEC disturbances by transporting the plasma from the east to the west through the epicenter meridian, as it is seen in the observations and simulations results. Finally, we should mention, that according to the GPS data, the strong TEC disturbances are clearly visible in the area North-East of the epicenter (Fig. la). At the first glance, they are similar to the ionospheric precursors of earthquakes, but their morphology is not consistent with the previously reported features o f the pre-seismic TEC disturbances (Namgaladze et al., 2013 and references in it). Firstly, there are no effects near the magnetically conjugated point in the Southern hemisphere. Secondly, these regions appeared in the GIM-TEC for the first time at 110