Cosmic ray flux variations,modulated by the solar and terrestrial magnetic fields,and climate changes. Part 2: The time interval from ∼10000 to ∼100000 years ago

A joint analysis of paleodata on variations in cosmic ray fluxes, solar activity, geomagnetic field, and climate during the period from ～10000 to ～100000 years ago has been performed. Data on the time variations in the concentration of ¹⁴C and ¹⁰Be cosmogenic isotopes, which are generated in the Earth’s atmosphere under the action of cosmic ray fluxes modulated by solar activity and geomagnetic field variations, were used to detect variations in solar activity and the geomagnetic dipole. Information about climate changes has been obtained mainly from variations in the concentration of stable isotopes in the natural archives. A performed analysis indicates that the variations in cosmic ray fluxes under the action of variations in the geomagnetic field and solar activity are apparently one of the most effective natural factors of long-term climate changeability on a large time scale.     

Comparison of the sector and usual spherical harmonic analyses of the solar magnetic field in July 2004

It has been shown that sector spherical harmonic analysis, in contrast to the usual harmonic analysis, allows for an exact coordination of the solar magnetic field from the photosphere to the Earth’s orbit.     

Regions of the maximal cosmic ray energy release in the atmosphere

The cosmic ray flux through the atmosphere at different levels of solar activity is simulated. The Geant program package has been used to determine the atmospheric zones where the maximal contrast of the released ray energy originates between the periods of solar minimum and maximum. The geographic coordinates and altitudes of these zones have been calculated. The results can be used to search for statistical correlations between the solar activity variations and dynamics of atmospheric transparency.     

Computerized streamflow measurement using slug injection

Using current meters to estimate flows in fast mountain streams is difficult and inaccurate. The salt dilution method offers an easier and more accurate alternative. The method has been used for many years but is time consuming and messy because of the need to mix chemical solutions and measure chemical concentrations in the field. A computer program has been developed which uses a laptop computer to calculate the mixing length and the mass of salt needed. The program controls the conductivity measurements and calculates the streamflow directly in the field. The development of this program is described and examples are presented of the application of the method in the Rocky Mountains of Alberta and British Columbia.     

Calculation of the interplanetary magnetic field based on its value in the solar photosphere

The difficulties associated with calculating the parameters of the interplanetary magnetic field (IMF) from solar magnetic data have been considered. All conventional calculation patterns and available input databases have been analyzed from a unified standpoint. It has been shown that these assumptions and limitations cannot affect the general structure and dependence on cycle of solar and interplanetary data. At the same time, the measured solar field values are underestimated as a result of the magnetograph signal saturation effect. It has been shown that the correction should depend on the heliocentric observation latitude and cycle phase. The correction method responsible for good agreement between the calculated and measured values has been proposed. The created database makes it possible to quantitatively calculate the magnetic fields in the solar wind near the Earth.     

Magnetic field behavior in the magnetosheath when the IMF slightly differs from the solar wind velocity vector

The magnetic field behavior in the magnetosheath, when the IMF and the solar wind velocity are almost collinear, has been analyzed based on the perturbation method. Magnetic disturbances are considered against a background of the stationary MHD solar wind flow around the magnetosphere when the magnetic field and the solar wind velocity are strictly collinear. It has been indicated that the angle between the magnetic field and velocity vectors increases considerably in a relatively thin layer near the magnetopause. The angle rise factor profiles have been determined for different distances from the subsolar point. The thickness of the layer, where the angle reaches values of about unity and more, has been estimated. It is important to take this layer into account when the magnetopause stability with respect to Kelvin-Helmholtz waves is analyzed.     

Global electromagnetic induction in the Moon and planets

A summary of experiments and analyses concerning electromagnetic induction in the Moon and other extraterrestrial bodies is presented. Magnetic step-transient measurements made on the lunar dark side show the eddy current response to be the dominant induction mode of the Moon. Analysis of the poloidal field decay of the eddy currents has yielded a range of monotonic conductivity profiles for the lunar interior: the conductivity rises from 3·10^?4 mho/m at a depth of 170 km to 10^?2 mho/m at 1000 km depth. The static magnetization field induction has been measured and the whole-Moon relative magnetic permeability has been calculated to be $\text{μ}\text{μ}{}_0\text{= 1.01 ± 0.06}$. The remanent magnetic fields, measured at Apollo landing sites, range from 3 to 327 γ. Simultaneous magnetometer and solar wind spectrometer measurements show that the 38-γ remanent field at the Apollo 12 site is compressed to 54 γ by a solar wind pressure increase of 7·10^?8 dyn/cm². The solar wind confines the induced lunar poloidal field; the field is compressed to the surface on the lunar subsolar side and extends out into a cylindrical cavity on the lunar antisolar side. This solar wind confinement is modeled in the laboratory by a magnetic dipole enclosed in a superconducting lead cylinder; results show that the induced poloidal field geometry is modified in a manner similar to that measured on the Moon. Induction concepts developed for the Moon are extended to estimate the electromagnetic response of other bodies in the solar system.     

Analysis of large-scale horizontal velocities and the magnetic field on the sun during fast reorganization periods

The velocity field of large-scale magnetic structures during fast reorganizations of the global solar magnetic field structure has been analyzed. Some characteristic features of the velocity field have been found during these periods. At that time, a considerable part of the solar surface is occupied by regions with low horizontal velocities, which correspond to the regions of positive and negative velocity field divergence during the solar activity growth and decline phases, respectively. Such character of changes in the velocity field during these periods agrees with the previously proposed scenario of magnetic field variations during global reorganizations of the magnetic field structure. The average horizontal velocities during a Carrington rotation and their divergence have been calculated for Carrington rotations from 1646 to 2006. Relatively slow regular variations in these parameters as well as their abrupt changes, observed during different solar cycle phases, have been revealed. An increase in the average horizontal velocity during the solar activity growth phase is most probably caused by relative motions of the regions with a new emerging magnetic flux. We assume that abrupt increases in the average horizontal velocity divergence are related to fast reorganizations of the magnetic field structure.     

Correlation between the near-Earth solar wind parameters and the source surface magnetic field

The solar magnetic field B _s at the Earth’s projection onto the solar-wind source surface has been calculated for each day over a long time interval (1976–2004). These data have been compared with the daily mean solar wind (SW) velocities and various components of the interplanetary magnetic field (IMF) near the Earth. The statistical analysis has revealed a rather close relationship between the solar-wind parameters near the Sun and near the Earth in the periods without significant sporadic solar and interplanetary disturbances. Empirical numerical models have been proposed for calculating the solar-wind velocity, IMF intensity, and IMF longitudinal and B _z components from the solar magnetic data. In all these models, the B _s value plays the main role. It is shown that, under quiet or weakly disturbed conditions, the variations in the geomagnetic activity index Ap can be forecasted for 3–5 days ahead on the basis of solar magnetic observations. Such a forecast proves to be more reliable than the forecasts based on the traditional methods.     

Empirical model of the OI 630 nm emission variations. 3. Emitting layer height

The empirical model of variations in the emitting layer height and parameters has been developed based on an analysis of the rocket measurements of the vertical distributions in the 630 nm intensity. The dependences on the solar zenith angle during a day are most substantial. This dependence is responsible for the character of seasonal variations at different latitudes. The height of the emitting layer increases with increasing solar activity, reflecting a temperature rise in the upper atmosphere. The negative trend—0.35 km yr^?1 in the interval 1964–1990—has been revealed.     

Analytical configurations of a force-free magnetic cylinder in the solar wind

The problem of a smooth field configuration, which should be an initial configuration in modeling (using the method of coarse particles) the problem of a stationary solar wind flow around a magnetic cloud in the case of a spatially two-dimensional statement (when a magnetic cloud is considered as a force-free magnetic cylinder with a finite radius) is considered. It has been indicated that such a statement is possible only when the magnetic field in the solar wind is parallel to the cylinder axis. The method for finding the magnetic field of a force-free cylinder with a finite radius, when some field component is specified and another component is determined based on this one (which makes it possible to construct fields with preassigned properties), has been proposed. The variant for constructing the initial field configuration in the transition region around a cylinder has been proposed. This variant makes it possible to gradually pass from homogeneous crossed fields in the solar wind to a force-free magnetic and zero electric fields within a cylinder, an electric field being potential and orthogonal to a magnetic field (in the reference system related to a magnetic cloud).     

ANN测井相分析方法研究

本文研究了用于测井相分析识别岩性的人工神经网络（ＡＮＮ）模型设计并在ＳＵＮ工作站上用基于距离Ｄ－ＫｏｈｏｎｅｎＮＮ、Ｄ－ＢＰＮＮ两个网络建立了ＡＮＮ自动测井相分析系统。在实际应用中对比了ＡＷ岩相识别和传统多元统计岩相识别的效果，证明了ＡＮＮ模式识别技术用于测井相分析的可行性和优越性。     

Improved indirect phase reflection height measurement at panská ves — method,equipment, evaluation

Summary Indirect phase reflection height measurements have been performed at the Panská Ves Observatory, Czechoslovakia, for 30 years to monitor solar flare effects (SFA). Only after introducing the new receiver in May 1985, could the indirect phase height analysis (IPHA) method be applied to measurements along the Allouis — Panská Ves 162 kHJ measuring path. The IPHA method allows the electron density and pressure variability in the lower ionosphere to be studied, particularly near the 80 km altitude. This paper describes the theoretical background of the IPHA method, the measuring equipment used at Panská Ves, the method of evaluating records and checking of data, and the program package developed by us both for graphic and numerical processing, as well as our efforts to develop a homogeneous East European IPHA network. The IPHA method has been introduced succesfully at the Panská Ves Observatory.     

Determination of magnetic cloud parameters and prediction of magnetic storm intensity

A program for identifying magnetic clouds in patrol satellite data, which recorded the interplanetary medium parameters near the magnetosphere, has been developed based on the cloud model in the form of a force-free cylindrical flux tube. The program makes it possible to also determine the entire magnetic field distribution in a cloud that approaches the Earth, using the initial satellite measurements. For this purpose, a model cloud (which has the maximal correlation coefficient with an analyzed cloud with respect to three magnetic field vector components and minimal rms deviations of the magnetic field and velocity components) is selected from the preliminarily created database including 2 million model clouds. The obtained magnetic field distribution in a cloud will make it possible to predict the intensity of a magnetic storm that this cloud will cause.     

MHD nature of the origination,dynamics, geoeffectiveness,and disappearance of the four-sector structure of the solar magnetic field during the cycle 23 decline phase

The MHD nature of the origination, dynamics, geoeffectiveness, and disappearance of the four-sector structure of the solar magnetic field during the cycle 23 decline phase has been established. A prolonged ordered MHD process including the chain of the interrelated phenomena (unknown before this study), which begin and end in one of the main zones of active longitudes and are responsible for the above nature of the four-sector structure, has been detected as a result of the simulation of the large-scale open solar magnetic field and an analysis of the dynamics of this field fluxes. These phenomena are as follows: the extreme concentration of the photospheric field sources of the same sign in the zone of active longitudes; blocking of regular differential rotation by these sources; origination of a nonstationary MHD disturbance in the form of a four-sector structure, traveling in the direction of solar rotation at a nearly Alfvén velocity; upset of blocking, displacement of blocking sources from the zone, and their shearing motion relative to a traveling MHD disturbance; deceleration and dissipation of a four-sector MHD disturbance; and reconstruction of a bisector structure. The interactions during this process, which lasted from May 2004 to December 2005, were accompanied by the generation of an ordered succession of heliospheric and solar-terrestrial disturbances including the series of nine extrastorms that were observed from July 2004 to September 2005 and were the last storms in the finished cycle 23 of solar activity.     

Global Survey Method for the World Network of Neutron Monitors

One of the variants of the global survey method developed and used for many years at the Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation of the Russian Academy of Sciences is described. Data from the world network of neutron monitors for every hour from July 1957 to the present has been processed by this method. A consistent continuous series of hourly characteristics of variation of the density and vector anisotropy of cosmic rays with a rigidity of 10 GV is obtained. A database of Forbush decreases in galactic cosmic rays caused by large-scale disturbances of the interplanetary medium for more than half a century has been created based on this series. The capabilities of the database make it possible to perform a correlation analysis of various parameters of the space environment (characteristics of the Sun, solar wind, and interplanetary magnetic field) with the parameters of cosmic rays and to study their interrelationships in the solar–terrestrial space. The features of reception coefficients for different stations are considered, which allows the transition from variations according to ground measurements to variations of primary cosmic rays. The advantages and disadvantages of this variant of the global survey method and the opportunities for its development and improvement are assessed. The developed method makes it possible to minimize the problems of the network of neutron monitors and to make significant use of its advantages.     

A procedure for automated analysis of brief pumping tests of domestic wells

A new computer program has been developed to automate analysis of brief single-well pumping tests. Adapted from a procedure developed by Picking (1994) that does not require measurement of the pumping rate, this new program is menu-driven and eliminates one significant source of imprecision in Picking's original method, namely, selection of "well function of u" values by interpolation in a lookup table. This new program has been applied to tests of 25 domestic wells penetrating bedrock, each pumped for <2 min.     

Effect of active longitudes in cosmic ray flux modulation

Galactic cosmic rays, registered by ground-based neutron monitors, are strongly affected by the heliosphere, i.e., being subjected to solar modulation. Cosmic ray variations are closely related to different solar activity indices and IMF parameters. The longitudinal inhomogeneity of the general solar magnetic field as a star and the manifestation of this inhomogeneity in the magnetic field are considered in the work. It has been established that the longitudinal inhomogeneity of this field, with the dipole distribution of polarities along heliolongitude, mainly contributes to 27-day modulation of galactic cosmic rays.     

太阳活动,磁暴与震前大气电场异常关系研究

通过对太阳活动,磁暴与大气电场异常关系的研究及１９９７年９月至１９９８年８月白家疃台大气电场和磁暴实际观测结果的分析,论述了震前观测到的大气电场负异常现象与太阳活动和磁暴现象无明显相关。