Time–Latitudinal Development of the White-Light Coronal Structures over a Solar Cycle

Large-scale coronal structures (helmet streamers) observed in the white-light corona during total solar eclipses and/or with ground-based coronagraphs are mostly located only above quiescent types of prominences. These helmet streamers are maintained due to the magnetic fields of the Sun. Time–latitudinal distribution of prominences during a solar cycle, however, shows both the poleward and equatorward migrations, similar to the 530.3 nm emission corona (the green corona) intensities. Distribution of observed coronal helmet streamers during total solar eclipses, enlarged with the helmet streamers as were obtained by the ground-based coronagraph observations, are compared with the heliographic distribution of prominences and the green corona intensities for the first time. It is shown that the distribution of above-mentioned helmet streamers, reflects – roughly – the time–latitudinal distribution of prominences and emission corona branches, and migrates together with them over a solar cycle.     

Assessing the Effect of Spacecraft Motion on Single-Spacecraft Solar Wind Tracking Techniques

Recent advances in wide-angle imaging by the Solar Mass Ejection Imager (SMEI) on board the Coriolis spacecraft and more recently by the Heliospheric Imagers (HI) aboard NASA’s Solar TErrestrial RElations Observatory (STEREO), have enabled solar wind transients to be imaged and tracked from the Sun to 1 AU and beyond. In this paper we consider two of the techniques that have been used to determine the propagation characteristics of solar wind transients based on single-spacecraft observations, in particular propagation direction and radial speed. These techniques usually assume that the observing spacecraft remains stationary for the duration of observation of the solar wind transient. We determine the inaccuracy introduced by this assumption for the two STEREO spacecraft and find that it can be significant, and it can lead to an overestimation of the transient velocity as seen from STEREO-A and an underestimation as seen by STEREO-B. This has implications for the prediction or solar wind transients at 1 AU and hence is important for the study of space weather.     

Tidal and rotational distortions in figures of Pluto and Charon

The supposition is, the tidal and rotational distortions should be fully responsible for the Pluto's and Charon's figure parameters. The mean polar and equatorial flattenings have been estimated about 10^–3, the second sectorial Stokes parameters about 9 × 10^–5, the differences between equatorial principal moments of inertia about 6 × 10³⁰ kg m² (Pluto) and 2 × 10²⁹ kg m² (Charon).     

Time-Latitudinal Dynamics of Magnetic Fields and the Green Corona Over Three Solar Cycles

Time-latitudinal distributions of the solar-surface magnetic fields and the green corona (530.3 nm, Fe XIV) intensities in the period 1975 – 2004 are analyzed. Meridional migration maps show that time-varying components consist of both the poleward and equatorward belts over a solar cycle. The green-corona maps are, for the first time, directly compared with magnetic flux charts, yielding a good association between the green corona and magnetic fields; this is most reliably seen at high latitudes.     

Blue, complexly zoned, (Na,Mg,Fe,Li)-rich beryl from quartz-calcite veins in low-grade metamorphosed Fe-deposit Sk��ly near Ryma?ov, Czech Republic

Syn-tectonic quartz-calcite veins containing blue beryl are enclosed in hematite > magnetite-rich portions of the low-grade metamorphosed Fe-deposit Skály near Ryma?ov, Czech Republic. Aggregates of pale to deep blue beryl, up to 2?cm in diameter, are associated with euclase, clinochlore, hematite, albite and dravite. Complexly zoned beryl crystals consist of skeletal aggregates of beryl I randomly distributed within volumetrically dominant beryl II with narrow rims of beryl III. All types of beryl have similar contents of Na (0.32?C0.49 apfu) and Mg (0.31?C0.41 apfu) but variable contents of Fe_tot (0.05?C0.34 apfu) and Al (1.20?C1.62 apfu). The LA-ICP-MS study yielded elevated contents of Li, up 1,314?ppm (0.28?wt.% Li₂O) in beryl I. The quartz-calcite veins represent an unusual type of low-T metamorphic-hydrothermal vein related to Fe-ore deposit characterized by single-stage fracturing and mobilization in a closed system at T~200?C300°C and CO ₃ ^2- as a major complexing agent for the mobility of Be.     

Expanding earth hypothesis and the Earth's gravitational potential energy

Summary The gravitational potential energy of the actual Earth has now been estimated at –2·485 × 10³² J. Three density models of the hypothetical Earth before the hypothetical expansion have been adopted for estimating the internal energy necessary for expanding: 7 × 10³¹ J. No dynamical evidence exists for the origin of this energy in the last 450 × 10⁶ y. The hypothetical increase in the Earth's mass M of about 0·4 M since 2 × 10⁸ y B.P. required for a dynamical balance has also no support in the paleodynamics of the Earth-Moon-Sun system since the M. Ordovician.Dedicated to the Memory of K. P     

Evolution of cultural landscape in the Northern Bohemian Coal mining Region on the background of socio-economic transformations

The NW part of Bohemia belongs to the most intensely exploited territories, both from the functional and ecological standpoints. In a sense, it is an open air laborarory, offering many topics to be discussed, researched and solved. The author strives to give a sociogeographical outline of the current state, with respect to the landscape evolution. This picture focuses on historical developments in recent decades as well.Rapid economic expansion of the examined territory started in the second half of the 19th century, having followed the pre-industrial period. A similar abrupt change of social and economic structures occurred 100 years later, in the post-war period. It was the growth of open-cast brown coal mining and corresponding activities (especially coal-fired plants) which resulted in large scale environmental disturbances, affected the settlement system and harmed the health of the population. Thus, further economic and ecological development should be based on a reclamation of the previous state.     

Cultural and social dimensions of borderlands: The case of the Italo-Slovene trans-border area

The article represents an attempt to explore the dimensions of border landscapes on the basis of some recent theoretical and methodological geographical trends in approaching such kind of regions and in the case of a special part of the current Italo-Slovene transborder area — the Gorizia section. Here, the contradiction between the stability of trans-border cultural and social links and the lability of the political partition seems to be particularly sharp. As a consequence, the border population try to reproduce the traditional spatial and social milieu in which it used to live before changes in international political framework occurred. Field methods for the detection of local social and cultural trans-border relations are then introduced, disclosing both the extent and qualities of the Gorizia trans-border region.     

Effects of long term nutrient and climate variability on subfossil Cladocera in a deep,subalpine lake (Lake Garda,northern Italy)

Albeit subfossil Cladocera remains are considered as a reliable proxy for tracking historical lake development, they have been scarcely studied in large subalpine lakes south of the Alps. In this study, subfossil Cladocera remains from Lake Garda in northern Italy were analyzed to track the lake’s environmental changes since the Middle Ages. One core was retrieved from the largest sub-basin of Lake Garda (Brenzone, 350 m deep) and two cores were retrieved from the profundal and littoral zone of the smaller lake sub-basin (Bardolino, 80 and 40 m deep, respectively). The species distribution of Cladocera remains in recent sediment layers was similar to that observed in contemporary water samples. The deepest sections of the three cores were characterized by species sensitive to water temperature, which suggest a key role of major climatic events in driving the lake response during the late Holocene. The most evident change in Cladocera assemblages in the studied cores was observed during the 1960s, when planktonic taxa such as Daphnia spp. and Bosmina spp. became dominant at the expense of littoral taxa. Despite the highly coherent general pattern of subfossil Cladocera, the cores showed a set of minor differences, which were attributed to different morphological and hydrological features of the two basins forming Lake Garda. Multivariate analysis revealed a clear relation of Cladocera to climate variability during periods of low lake nutrient levels (i.e. before the 1960s). This provides additional information on past ecological responses of Lake Garda, as contrast previous data from subfossil diatom and pigment analyses did not fully capture effects of climate change during the same period. Since the 1960s shifts in assemblage composition of Cladocera and diatoms were highly coherent, in response to nutrient increase and the following, less pronounced, decrease in nutrient concentrations. During the last five decades, the response of the Cladocera to climate variability appeared to be masked by nutrient change. This work points up the potential of the multi-proxy approach for disentangling the multifaceted biological responses to multiple environmental stressors in large and deep lakes.     

THE USE OF GEOGRAPHIC INFORMATION SYSTEMS IN ANALYSIS OF URBAN AND RURAL LANDSCAPES

This paper reviews major concerns in the development of geographic information systems in Czechoslovakia (underlying theory, design and system requirements, data acquisition and classification, and mathematical-cartographic modeling), and describes the structure of two systems developed for the city of Brno and the surrounding semi-rural countryside. These systems are designed to permit the widest possible range of spatial information to be incorporated into their data bases, to allow maximum flexibility of response to changing user requirements, to produce a wide variety of graphic products, and to provide a capacity for automated forecasting and output of forecast maps. Presented at the Euro-Carto III Seminar sponsored by the International Cartographic Association at Graz, Austria, October 23-25, 1984 and submitted to the Editor-in-Chief for publication.