V. I. Odintsov, A. N. Zaitzev, V. G. Petrov, A. S. Amiantov
Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Russian Academy of Sciences, Troitsk near Moscow, 142092, RUSSIA, E-mail: zaitzev@izmiran.rssi.ru
The digital variometers were introduced on Soviet magnetic observatories since 1975 in the frame of US-USSR experiment with ATS-6 satellite. The necessary experience and data processing system was developed during next decade and since 1985 some observatories begun to collect continuous digital data sets. The results of observations for this initial stage were summarized for the period 1984-1994 in 1-min binary MAG-format on the CD-ROM, which was presented at IUGGÒ95. Now we are in the second stage when digital registration becomes a basic method of observations and magnetic variational data available almost in real-time via Internet. The regular digital registration of the geomagnetic field variations was introduced in Moscow magnetic observatory of IZMIRAN since May 1991. We use the CMVS-6 quartz digital variation station with data storage on the audiocassette. Recently we add the VHF radio-link where data transmitted every 0.5 sec to the PC-type computer connected within local network to the Internet server. With the special software the instant data loaded in PC and converted in 1-min MAG-format data. Each hour data block added to daily file and displayed in real-time on server http://helios.izmiran.troitsk.ru/cosray/magnet.htm.
We collect the magnetic variational data of Moscow observatory for the period 1991-1999 in 1-min binary MAG-format. Recently we produced the second CD-ROM "Russian Geomagnetic Observatories Data Base 1992-1999, Vol. 2", which include 1-min. data of Moscow magnetic observatory and other observatories as Cape Schmidt, Ekaterinburg (Arti), Irkutsk, Loparskaya, Lovozero and expedition points Cape Kamenny and Seykha. The access to data base via CD-ROM stimulates a wide usage of observatory data.
The new information technology lead to changes in the research methods, which we used for analysis of geomagnetic disturbances. One of such method based on the adaptive narrow-band filtration, which allow us to separate the geomagnetic field variations on the harmonic components in the form of time-spectral graphs. The samples of such graphs are displayed on the site http://www.izmiran.rssi.ru/magnetism/mos_data.htm. The analysis of spectral features of severe magnetic storms led to the new conclusions about the magnetosphere disturbances and its connection with solar wind parameters. Some recent results are presented in this paper.