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31.
The application of the single Doppler radar dataset analysis is usually confined to the assumption that the actual wind is linearly distributed or uniform locally.Following some dynamic features of convective weather,a conceptual model of moderate complexity is constructed,wherewith a horizontal wind perturbation field is retrieved directly from the single Doppler radar measurements.The numerical experiments are based on a 3-D cloud model-generated convective cell,whose radial velocity component is taken as the radar observations that are put into the closed equations based on the conceptual model to retrieve the horizontal wind perturbation field.After the initial field is properly treated,the retrieval equation is solved in terms of the 2-D FFT technique and the sensitivity to noise is examined.Finally,contrast analysis is done of the retrieved and the cloud model output wind fields,indicating the usefulness of the approach proposed in this paper.  相似文献   
32.
Amidst metavolcanic rocks and phyllites of the Góry Kaczawskie region occur isolated carbonate bodies known as the Wojcieszów limestones. The bodies enclosed in the metavolcanites show primary (sedimentary) contacts, while those in the phyllites do not have such contacts. The Wojcieszów limestones and metavolcanic rocks form sequences displaying mutual spatial and genetical relations. Submarine volcanic elevations were covered with chemical and biochemical carbonate precipitation, the intensity of which was stimulated and controlled by the volcanic activity.
Zusammenfassung Inmitten der metavulkanischen Gesteine und Phyllite von Góry Kaczawskie erscheinen isolierte Karbonatgesteinskörper, die als Wojcieszów-Kalke bekannt sind. Die Karbonatgesteine innerhalb der Metavulkanite zeigen sedimentäre Kontakte, während die in den Phylliten eher tektonisch begrenzt sind. So kann man den Wojcieszów-Kalken und den Metavulkaniten eine räumliche und genetische Beziehung zusprechen. Submarine Erhebungen aus Vulkangesteinen waren mit chemischen und biochemisch gefällten Karbonatserien bedeckt, wobei die vulkanische Aktivität die Karbonatbildung unmittelbar beeinflu\te.

Résumé Parmi les métavolcanites et les phyllites de la région du Góry Kaczawskie, il existe des corps carbonatés isolés connus sous le nom de »calcaires de Wojcieszów«. Ceux qui sont inclus dans les métavolcanites présentent des contacts sédimentaires, contrairement à ceux qui sont inclus dans les phyllites, dont les contacts sont tectoniques. Entre les calcaires de Wojcieszów et les roches métavolcaniques, il est donc possible d'établir des relations spatiales et génétiques. Des reliefs volcaniques sous-marins ont été le siège d'une précipitation carbonatée chimique et biochimique dont l'intensité dépendait de l'activité volcanique.

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Measurements of topsoil magnetic susceptibility are often used for quick assessment of soil contamination of anthropogenic origin, with heavy metals or other pollutants. However, because of complicated correlations between low-field magnetic susceptibility (shortened to magnetic susceptibility) of topsoil and soil pollution, the outcome of a field magnetometry survey can not be related directly to soil pollution. For each case study, the results should be interpreted on their own taking into account not only the type of pollution but also pedogenic, biogenic and environmental factors. In practice, it is very difficult to measure and consider all these factors. Here we illustrate the merit of geostatistical methods, which are focused on the spatial variability of a phenomenon, in the interpretation of soil magnetometry results. This article presents the analysis of spatial variability of top soil layers magnetic susceptibility-within the Upper Silesia Industrial Region (USIR)-using semivariance analysis. It also explains how to adjust the sampling density of field magnetometry measurements to spatial variability of the soil pollution as well as to the spatial scale of the investigated area. For this purpose, the values of magnetic susceptibility have been measured by using various sampling densities at areas of different size located within USIR. This enabled to determine the main scales of magnetic susceptibility spatial variability of soils within USIR using semivariance. A few distinct scales of variability were found from the site scale to a more regional scale. Variability ranges of 30 km, 12 km, and 5 km refer to the large regional scale, whereas smaller ranges of few hundreds down to a few tens of meters, can be attributed to the local (site) scale. In addition, the precision of the measuring campaigns, performed within USIR with different sampling densities, was compared through the analysis of the spatial variability of the soil magnetic susceptibility signal by using ordinary kriging. jarek97@yahoo.com, piotr.fabijanczyk@is.pw.edu.pl  相似文献   
35.
Ecological conflicts in Poland   总被引:1,自引:0,他引:1  
Transformation of the political system, observed in Poland for 10 years in connection with economic restructuring and basic socio-economic reforms to harmonise with European Union structures, is also evident in terms of environmental management. Pollution has been reduced in many ways but the rise in living standards, linked with the rapid growth of cars and other forms of consumption, has had a negative effect and environmental conditions have deteriorated in the central areas of large cities. The growth of waste water and refuse is a considerable problem. More areas are now officially protected and the three levels of local government established at the beginning of January 1999 (voivodeship, district and community) all have certain defined environmental protection responsibilities which are cumulatively greater than before. Meanwhile there is a greater awareness in society of environmental issues, although it does not yet lead to a high level of participation in protection work. However, there are strongly-expressed opinions on the ecological acceptability of certain economic developments and conflicts are frequently arising within communities and local governments and also between investors on the one side and ecological organisations and environmental protection institutions on the other. Most controversial are new roads, power stations (like the Zarnowiec nuclear project) and reservoirs like the one on the Dunajec river at Czorsztyn. Local communities frequently resist plans for waste dumps, incinerating plants and other developments which are seen as injurious to health or the quality of life. The planned reprivatisation of the state-owned forests is also criticised by foresters and ecological movements. Conflicts are likely to grow as economic development accelerates but better information and greater public understanding of the need for sustainability should make for consensus. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
36.
Fault network of the Upper Silesian Coal Basin (USCB) is built of sets of strike-slip, oblique-slip and dip-slip faults. It is a typical product of force couple which acts evenly with the parallel of latitude, causing horizontal and anti-clockwise movement of rock-mass. Earlier research of focal mechanisms of mine tremors, using a standard fault plane solution, has shown that some events are related to tectonic directions in main structural units of the USCB. An attempt was undertaken to analyze the records of mine tremors from the period 1992–1994 in the selected coal fields. The digital records of about 200 mine tremors with energy larger than 1×104 J (M L >1.23) were analyzed with SMT software for seismic moment tensor inversion. The decomposition of seismic moment tensor of mine tremors was segmented into isotropic (I) part, compensated linear vector dipole (CLVD) part and double-couple (DC) part. The DC part is prevalent (up to 70%) in the majority of quakes from the central region of the USCB. A group of mine tremors with large I element (up to 50%) can also be observed. The spatial orientation of the fault and auxiliary planes were obtained from the computations for the seismic moment DC part. Study of the DC part of the seismic moment tensor made it possible for us to separate the group of events which might be acknowledged to have their origin in unstable energy release on surfaces of faults forming a regional structural pattern. The possible influence of the Cainozoic tectonic history of the USCB on the recent shape of stress field is discussed.  相似文献   
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Summary Two groups of basaltic rocks with normal and reversed NRM were examined. It was found that in both groups the primary NRM, synchronous with the period of rock formation, is preserved. Relations of the primary NRM to the origin and the degree of oxidation of magnetic minerals were considered in detail.  相似文献   
39.
Eccentricity resonances between the secular motion of an Earth satellite's orbit and the longitudes of the Sun and the Moon are studied within a Hamiltonian framework. The problem is approximated in a traditional manner, with the Earth's potential including only the second zonal harmonic, and a Hill‐type approximation for perturbing bodies. For a family of 10 resonances, stable and unstable points are identified and libration widths are estimated. Numerical values are given for the maximum variation of eccentricity available at each resonance. The respective amplitudes of the perigee heights' librations range from 2 to 750 km. The resonances of the solar origin are generally stronger than their lunar counterparts. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
40.
The Petryanov air filters combined into half-year sets were analyzed for the presence of 40K, 137Cs and 22Na by means of low-background gamma rays spectrometry. Each sample contains aerosols from more than 1 Mm3 of air. Samples were collected in ground level air at Kraków (Southern Poland) from 1996 to 2002. Activity concentrations of 40K are almost constant with the mean of 14.7± 4.5 Bq m–3. Activity concentrations of 137Cs, which are on the level of single Bq m– 3 show exponential decrease with effective half-life time of 7.07± 0.77 years. The cosmogenic 22Na shows a strong seasonal variation with significant different mean values activity concentration between 0.333± 0.095 Bq m–3 and 0.137± 0.045 Bq m–3, for summer and winter, respectively. Moreover, the activity ratio for two cosmogenic radionuclides: 22Na and measured previously 7Be show also changes with statistically significant seasonal differences. The lower values were found during winters. The mechanisms which might govern this ratio are discussed. The conclusion is that transport of 22Na during summer seems to be so much effective, that results in kind of relative depletion of stratosphere of this nuclide.  相似文献   
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