ИСТИНА

Magnetic disturbances on the ground, being the images of processes of solar-wind/magnetosphere interaction, can be monitored by comparing time-series of magnetic records on the ground with the space weather parameters. However, a serious drawback of the analysis of ground-based magnetograms is the inevitable variation of the magnetic response due to continual changes of the station location. An ideal, but impossible, solution of this difficulty, that will help to discriminate temporal and spatial variations, would be the deployment of a “stationary” observatory with a fixed position in the solar-magnetospheric coordinate system. However, the desired result can be obtained with the proposed technique of “virtual magnetograms” (VM). This technique has been implemented for key magnetospheric domains (midnight auroral and dayside cusp regions) as an additional tool for monitoring the response of the geomagnetic field to the solar wind and interplanetary magnetic field (IMF) forcing. VM for a fixed reference system is reconstructed by 2D spatial gridding of 1-min magnetic data from world-wide distributed magnetic stations. The VMs have been produced for the period since 1996 up to nowadays. A wide range of space physics studies, such as substorm triggering, solar wind-ionosphere interaction, sawtooth oscillations, ionospheric convection response to IMF variations, etc. will benefit from the introduction of the VMs. The database of calculated VMs for the dayside cusp and midnight auroral regions, as well as simultaneous interplanetary parameters (solar wind electric field) and geomagnetic indices (AE-index) are available via the specially designed site http://vm.gcras.ru/ for all interested researchers for testing and validation.