An abnormality among a series of geomagnetic quiescent days during July 1978 has been identified on 26 July using geomagnetic data from a network of 13 observatories in Indo-Russian longitude belt. This abnormality has been explained by invoking an additional clockwise loop current system centered around 5° dip latitude superimposed on the normal S_q current system centered at 20° dip latitude, thereby shifting the focus of the combined current system to 35° dip latitude. Probable causes of this additional currents in the low-latitude have been discussed.

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EISCAT data obtained in the auroral ionosphere have been analyzed in terms of the E-region neutral wind behavior at three heights of 101, 109, and 119 km. We have analyzed two extended CP-1-H runs conducted over four consecutive days each for 21-25 September 1987 and 16-20 March 1988. Mean winds as well as tidal amplitudes and phases derived by both Fast Fourier Transform (FFT) and least square fit (LSF) methods are compared with those of corresponding seasonal winds from the quiet-time statistical study by Brekke et al. (1994). During 21-25 September 1987 the mean zonal wind derived by FFT with filling in zeroes in the data gaps blows eastward with a maximum of ∼20 m s^-1 between 101 and 119 km and its direction is consistent with the average quiet-time fall wind. The directions of mean meridional and vertical winds, however, are opposite to those of the fall wind. The amplitudes and phases of the tidal winds are in reasonable agreement with those found. for fall quiet time. At 119 km the zonal wind shows a large enhancement during the very geomagnetically disturbed period between 16 UT on 22 September and 05 UT on 23 September and also for about 5 hours after the end of the disturbed period. During 16-20 March 1988 the amplitudes of the mean meridional and vertical winds are very small while the mean zonal wind blows eastward with a maximum of less than 18 m s^-1 between 101 and 119 km, which is about half as large as that of the average quiet-time spring wind. Most diurnal meridional and semidiurnal horizontal wind amplitudes between 101 and 119 km are also about half of those found for spring quiet time. The height profiles of phases for most components are much the same as those of the spring wind. Comparisons are made with results obtained by the Søndre Strømfjord IS radar and model predictions, and geomagnetic disturbance effects on the wind are discussed.

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Altitude distributions of mesospheric ozone were measured by rocket-borne radiometers in the polar region. The rocket observations were carried out in February and November, 1994 at Andoya (69°N, 16°E), Norway in the twilight condition. Mesospheric ozone densities in 60-100 km altitude region were measured by using the O₂ 1270 nm emission as well as the measurements of nitric oxide and stratospheric ozone densities. A clear secondary maximum of ozone density around 88 km and a deep valley around 78 km were seen in both months. The densities of the secondary maximum in February and November were 3.9 × 10⁷ cm^-3 and 7.1 × 10⁷ cm^-3, respectively.

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The magnetic anomaly fields (MAF) obtained from the data of gradient magnetic measurements at stratospheric altitudes along transcontinental routes, passing over the Russian territory, and from the Magsat satellite data are investigated. The stratospheric gradient measurements are shown to be more suitable for separating and interpreting regional magnetic anomalies of crustal sources as compared to the data obtained at aircraft and satellite altitudes. It is also shown that, at stratospheric altitudes, one should use the device for magnetic field measurements that contains three sensors spread uniformly along the vertical line within four kilometers. This allows us to obtain the rate of MAF change in the stratospheric layer, which makes it possible to study in more detail the geometry of sources and to estimate with high precision (about 1 km) the locations of positive and negative zones of the first (and second) vertical derivatives of MAF. In general, the stratospheric gradient surveys successfully supplement satellite ones.

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A new national geomagnetic network of repeat stations for total field F, horizontal component H, vertical component Z and declination D has been established in a collaboration between the Albanian Geological Society (Center for Geochemistry and Geophysics), the Tirana University (Albania) and the Istituto Nazionale di Geofisica (Italy). From the observed magnetic field elements all repeat stations were referred to Epoch 1994.75 and normal reference fields were computed in the form of 1st order polynomials in latitude and longitude. An overview of all work, including a brief history of the Albanian magnetic measurements, magnetic survey results, normal fields and secular variation estimates is presented.

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The alternating magnetic dynamo field of sea surface waves, a consequence of their Lorentz electric field, has been observed with a pair of simultaneously operated, closely spaced tri-axial magnetometers. Measurements from a magnetometer located in the centre of a tiny, uninhabited island served to compensate measurements from a near-shore magnetometer for magnetic pulsations of ionospheric origin, leaving the water wave dynamo field, effective close to shore only, as the dominant residual magnetic field. Amplitude and frequency of waves and swell were recorded with a vertical accelerometer (wave rider buoy), floating on the sea surface. The wave rider data are in good agreement with those obtained from the magnetometers. Amplitude and phase relations between the three vector components of the magnetic oscillations yield a sea surface wave vector which is consistent with the swell propagation direction usually found in that area. The magnetic field data further demonstrate that the water mass motion close to shore was not confined to a vertical plane (as would be the case for freely propagating gravity waves in the open ocean). The motion rather took place in a plane inclined at about 40° from the horizontal, which is roughly twice the inclination of the island flanks. We conclude that the magnetometer measurements yield a reasonably accurate description of the surface wave water motion within about one wavelength from shore.

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The transformation of isotropically distributed geomagnetic poles to local site directions introduces slight apparent inclination shallowing if the directional average is compared to the geocentric axial dipole direction. This effect depends on site latitude and pole dispersions. For typical dispersions of poles, 063 between 10° and 20°, the average inclination will appear too shallow by about 1° to 2° for site latitudes of 10° to 60° North or South. On the other hand, when some of the scatter might be due to isotropic scatter in directions, averaging all the data in polar space, will introduce a steepening effect. For most paleomagnetic studies this intrinsic inclination bias will be small in comparison with other uncertainties, typically of the order of 5° to 10°. However, for integrated high resolution studies of specific aspects of the geomagnetic field this methodological ambiguity might bias the results, and we caution against averaging paleomagnetic data only in directional space.

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