[en] The rediscovery that the Sun and the solar wind can undergo important changes on historical time scales has brought into question the stability of the cyclic behavior of past time series of solar and solar-terrestrial origin. It was found by Vector Fourier analysis that the solar 11 year cycle is present in the series of Br-10, delta 180, in ice cores and of thermoluminescence (TL) in sea sediments during the last Millennia with a frequency modulation, related to Sun behavior, as tested by comparison with the Sunspot number R sub z series. It was shown that the cyclogram of the series of yearly Aurorae from 1721 to 1979, linear-regression-corrected-for-R sub z is straight for the periodicity zeta=11,1y, which indicates that such periodicity, is constant in time, corresponding to the only line present in the 11y band. The maxima of this component appear at the same time together with the high speed solar wind streams taking place in coronal holes situated in high heliolatitudes. It is evidenced that the 11 year cycle has undergone frequency oscillations on a time scale of two centuries, although it is very difficult to determine the periodicities with high accuracy

[en] The vertical temperature profile of the lower troposphere can be measured with a radio-acoustic sounding system (RASS). A comparison of the thermal profiles measured with the RASS and with traditional methods shows a) RASS ability to produce vertical thermal profiles at an altitude range of 170 to 1000 m with temperature accuracy and height discrimination comparable with conventional soundings, b) advantages of remote sensing as offered by new sounder, c) applicability of RASS both in assessing evolution of thermodynamic conditions in PBL and in sensing conditions conducive to high concentrations of air pollutants at the ground level. (author)

[en] The thermoluminescence profile of an Ionian Sea recent sedimentary core, constructed with 467 equispaced data points and spanning 18 centuries from 170 to 1974 A.D. is studied. Several time series analysis methods reveal two evident periodicities on the centennial time scale, at 137 years and 118 years, both with their second harmonics. Together with these slow cyclic variations two sharp periodicities appear on the decennial time scale, at 12.1 years and 10.8 years. In the present study the amplitude and phase of these waves have been determined and it is shown that their summation accounts for more than 50% of the standard deviation of the whole time series and that they correctly reproduce the basic characteristics of the data

[en] The authors measured the thermoluminescence (TL) depth of the GT89/3 shallow-water Ionian sea core. This profile has been transformed into a time series using the accurate sedimentation rate previously determined by radiometric and tephroanalysis methods. The TL measurements were performed in samples of equal thickness of 2 mm, corresponding to a time interval of 3.096 y. The TL time series spans ∼ 1800 y. The DFT power spectral densities in the decadal periodicity range of this TL series show significant periodicities at 10.7, 11.3 and 12 y closely similar to the periodicities present in the sunspot number series. These results confirm that the TL signal in recent sea sediments faithfully records the solar variability, as we previously proposed

[en] A fundamental contribution to the understanding of several physical processes influencing the galactic-cosmic-ray (GCR) variations can be given by proxy data of the past GCR flux obtained in terrestrial archives and meteorites which extend the range of the studies. The most prominent spatial and temporal GCR variations are of solar origin. The solar modulation affect the intensity of GCR, particularly below 1 GeV and, therefore, the isotopes production rates in the Earth's atmosphere, in planetary surfaces and in meteorites where the GCRs induce nuclear interactions. Measurements and analyses of cosmogenic radioisotopes in terrestrial archives like tree rings, ice cores and sediments are presented. Effects due to variations in the geomagnetic field, climatic changes and exchange within different terrestrial reservoirs which affect the isotopes deposition rates are also discussed. The study of cosmogenic radioisotopes in meteorites, which are exposed to GCR in the interplanetary space, has the advantage that the production of radioisotopes is not affected by terrestrial processes

[en] Using an electrometric system operated in conjunction with a conventional particle array to detect extensive air showers (EAS), observations have been made on local changes of the atmospheric electric field connected with EAS. After a survey of the characteristics of the electrometric system, the data obtained during months of measurements are presented. These results suggest that changes of atmospheric electric field could be detected in connection with EAS of primary energy greater than 10¹⁶ eV

[en] The thermoluminescence (TL) profile of different recent Tyrrhenian sea cores sampled at various intervals during the last centuries have been compared in order to check the reproducibility of the profiles and investigate the possibility of using the results for monitoring solar-terrestrial relations in the past. The satisfactory results obtained by comparison of two different cores in the time interval 1755-1969 A.D. has demonstrated: (a) the two TL profiles are correlated; (b) the 11 yr cycle corresponding to the main solar cycle is evident in both TL profiles. (author)

[en] A meteorite shower fell at Torino, Italy on May 18, 1988. Petrographic studies indicate that the stone is an H6 chondrite having features of moderate to severe shock. Chemical analyses of the meteorite are reported. Cosmic ray produced He-3, Ne-21 and Xe-126 yield an exposure age of about 48 Ma. The cosmic ray track densities in three fragments range between 1.8 to 5 x 10 to the 5th/sq cm suggesting about 99 percent mass ablation in the atmosphere,. Twelve radioisotopes with half lives ranging between 5.6 days to 7.3 x 10 to the 5th years have been measured with high precision. Marginal signals were observed for several short-lived nuclides and upper limits were obtained for the activity levels of eight radionuclides, some of which have not been hitherto detected in fresh falls. The data are generally consistent with the nuclide production by galactic cosmic rays when modulation due to the solar cycle is taken into consideration. 23 refs

[en] The profile of thermoluminescence (TL) has been measured in the Ionian shallow-water core GT89-3 with a resolution of 3.096 years (corresponding to a sampling interval of 2 mm) during the last 1800 years. A similar TL record was previously obtained in the core GM14, taken from the same area, with a resolution of 3.87 years (corresponding to a sampling interval of 2.5 mm). The authors present here the comparison of the TL profiles. They confirm the presence of the centennial and the decennial cycles earlier identified in the TL signal, corresponding to cyclicities appearing to exist in the solar-activity records. It discusses the origin of the TL signal by comparison with the cosmogenic isotopes ¹⁴C and ¹⁰Be records

[en] The authors present data on small changes in the atmospheric electric field related to the passage of extensive air showers initiated by primary particles of energy (>=)10¹⁶ eV. Such changes were detected by electrometric methods in conjunction with a particle shower array