Russian Federal Service for Hydrometeorology

Russia, 129128, Moscow, Rostokinskaya st., 9

Tel.: 7(095)181-37-14 Fax: 7(095)187-81-86

e-mail: geophys@wmc.rssi.ru

hciag@sunny.aha.ru

  The Institute of Applied Geophysics deals with the scientific and applied aspects of solar-terrestrial monitoring system and forecasting service. Heliogeophysical Center in the Institute works for more than two decades as a National Space Weather forecast center as well as the European Regional Center (RWC Moscow) of the International Space Environment Service (ISES). It is responsible for gathering and processing of real time solar-geophysical data from the network, for providing solar, geomagnetic, ionospheric and space radiation predictions with different advance, and distributing the information to the users as well as exchanging these data with other RWCs.

The operational data network includes ground-based solar, ionospheric and geomagnetic observatories as well as a space segment, that consists of «Meteor» series satellites (polar orbit at 900 km altitude) and geostationary «Electro» satellites (85 deg. E). Being accumulated, the current network data form an observational base which is used for making short-term and medium-term forecasts. There also exists a rocket and lidar (satellite and ground-based) observation database of the principal parameters of the upper and middle atmosphere.

The Center is supported by Scientific and Technological Divisions which are making researh and are developing (in cooperation with corresponding Institutes of the Russian Academy of Sciences, Universities and Agencies) new facilities for regular observations and methods of diagnostics and forecasting of space weather parameters: solar and geomagnetic activity, energetic particle fluxes in the near-Earth space, and the state of the upper atmosphere and ionosphere. The Divisions also facilitate transition of research results into operations.

 1. Data on flux variations of ionizing EUV radiation for wavelengths shorter than 130 nm and in L-alpha hydrogen line were obtained on the basis of measurements performed on-board a Russian Earth-orbiting and interplanetary spacecrafts in the period since 1995 to 1998. These data were received by using common heritage instrumentation installed on INTERBALL-1 and the geosynchronous meteorological satellite ELECTRO. The time series of observations gives a possibility to estimate flux variations in the periods of the Solar 23-th cycle activity minimum (during the so-called UV hole) and during an 11-year cycle. During quiet periods of Solar activity (except for flares) a level of diurnal variations is rather low, it was found to be equal to about 3%.

 2. On the basis of analysis of the solar soft X--ray measurements during flares there was developed a world first analytical model – relations allowing to calculate a X--ray spectrum for a flare of arbitrary intensity in the waverange of 0.1--10 nm. An input parameter for calculation is flare radiation flux in 0.1--0.8 nm range. Direct measurement data were corrected on the basis of modeling ionospheric disturbances during X--ray flares, i.e. using of calculated spectra in ionospheric models should give values of E--layer critical frequency growth closed to the observed values. Such use of ionosphere as a natural detector of solar ionizing radiation makes possible to verify independently a calibration accuracy of instruments designed for direct observations of solar radiation.

 Nusinov, A.A., Chulankin D.I.. Soft X-Ray Solar Emission Variations During Flares. Geomagnetizm i Aeronomia, 1997, Vol. 37, No. 1, p. 14-23. (In Russian)

 3. A new aspect was considered in using EUV and X-ray fluxes for diagnostics and short-term prediction of proton radiation danger from the flare. The EUV (l <105 nm) and soft X-ray (0.1-0.8 nm) fluxes were compared for two types of solar flares. The first of them is followed by a strong enhancement in solar energetic (E>10 MeV) proton flux, the second one is not followed by any enhancement in proton flux. It was discovered that UV flux with a proton component was considerably higher than that in flares without protons, while soft X-ray fluxes were approximately equal. An excess of EUV emission in proton flares grows with increasing proton flux. An analytic expression was found for the growth in proton flux as a function of the excess of EUV radiation at a given X-ray flux. These results can be used in predicting flare radiation danger.

 4. A theoretical 3-D MHD model of the polar solar wind additional acceleration near the Sun due to the rotation of magnetized Sun was developed. The analytical solution with double electric layer at the heliocentric distance of 2.6 solar radii and the system of field aligned electric currents is the polar solar wind was obtained. The results could be used when planning missions to the Sun.

 Yu.V. Pisanko. The polar solar wind: a linear, force-free field, 3-D MHD model. Solar Physics, 1997, Vol. 172, pp. 345-352

 5. The global 3-D MHD model of the solar wind as a number of discontinuous solutions each describing adequately flow properties in the fixed local part of the Sun space environment was developed. The model was tested by comparison with independent models and available observations for the period of the Whole Sun Month Campaign (August-September 1996). The model is directed, in particular, to space weather applications.

 S.E. Gibson, D. Biesecker, M. Guhathakurta, J.T. Hoeksema, A. Lazarus, J. Linker, Z. Mikic, Yu. Pisanko, P. Riley, J. Steinberg, L. Strachan, A. Szabo, B. Thompson, X.P. Zhao. The three-dimensional coronal magnetic field during Whole Sun Month. The Astrophysical Journal, 1999 (in press) 

6.The ionospheric radio-sounding experiment on the MIR Space Station. An ionospheric sounder is installed on the MIR space station. One of the problems being solved is a real-time monitoring of the ionosphere and the determination of radio communication parameters. In this mode, the ionospheric sounder makes an ionospheric radiosounding on order from the ground and simultaneously transmits the resultant ionogram to the ground over a special radio channel with the frequency 137.85 MHz. This ionogram information can be received using a simple fixed antenna and receiver attached to a computer. All information processing and radio communication parameter calculations are made on this computer. The target information is the estimated Maximum Usable Frequency (MUF) and Lowest Usable Frequency (LUF) for an ionospheric radio communication link.

 N.P.Danilkin, The MIR space station ionospheric sounder, The Radio Science Bulletin, March 1999, No 288, pp. 14 - 17.

 7. Successful flight tests of the ALISSA lidar jointly developed and installed on the PRIRODA module of the orbital space statation MIR within the framework of the Russian French experiment on the lidar sounding of the atmosphere from space have been made. A number of scientific and methodical problems of lidar sounding of the atmosphere from space has been solved. Data on the height distribution of different types of cloudiness including the boundary layer and cirrostratus clouds (with 150m resolution) are obtained. An impact on the cloudiness of orographic processes occurring over mountains when they are being flown around by air masses is registered. These effects can be sources generating internal gravity waves propagating into the strato-mesosphere.

 G.F.Tulinov, V.E.Melnikov, M,B.Zhitkova, M.L.Chanin, R.C.Malique, M.Debois. Space lidar ALISSA for an orbital station MIR. Inzhenernaya ekologiya,1996,,No 5, pp.80-91.