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51.
Climatological drivers of changes in flood hazard in Germany   总被引:1,自引:0,他引:1  
Since several destructive floods have occurred in Germany in the last decades, it is of considerable interest and relevance (e.g., when undertaking flood defense design) to take a closer look at the climatic factors driving the changes in flood hazard in Germany. Even if there also exist non-climatic factors controlling the flood hazard, the present paper demonstrates that climate change is one main driver responsible for the increasing number of floods. Increasing trends in temperature have been found to be ubiquitous in Germany, with impact on air humidity and changes in (intense) precipitation. Growing trends in flood prone circulation pattern and heavy precipitation are significant in many regions of Germany over a multi-decade interval and this can be translated into the rise of flood hazard and flood risk.  相似文献   
52.
53.
Changes in thermal extremes of the climate of Poland in 1951–2010 are examined. Warm extremes have become more frequent, while cold extremes have become less frequent. In the warming climate of Poland, the increase in the number of extremely warm days in a year and the decrease in the number of extremely cold days in a year have been observed. Also the increase of the maximum number of consecutive hot days in a year and the decrease of the maximum number of consecutive very cold and extremely cold days in a year have been observed. However, the trends are not of ubiquitous statistic significance, as the natural variability is strong.  相似文献   
54.
Gradient-based similarity in the atmospheric boundary layer   总被引:2,自引:0,他引:2  
The “flux-based” and “gradient-based” similarity in the stable boundary layer and also in the interfacial part of the convective boundary layer is discussed. The stable case is examined on the basis of data collected during the CASES-99 experiment. Its interfacial counterpart is considered in both the quasi-steady (mid-day) and non-steady states, utilizing the results of large-eddy simulations. In the stable regime, the “gradient-based” approach is not unique and can be based on various master length scales. Three local master length scales are considered: the local Monin-Obukhov scale, the buoyancy scale, and the Ellison scale. In the convective “quasi-steady” (mid-day) case, the “mixed layer” scaling is shown to be valid in the mixed layer and invalid in the interfacial layer. The temperature variance profile in non-steady conditions can be expressed in terms of the convective temperature scale in the mixed layer. The analogous prediction for velocity variances is not valid under non-steady conditions.  相似文献   
55.
Nine profiles of the temperature structure parameter C T 2 and the standard deviation of vertical velocity fluctuations ( w) in the convective boundary layer (CBL) were obtained with a monostatic Doppler sodar during the second intensive field campaign of the First ISLSCP Field Experiment in 1987. The results were analyzed by using local similarity theory. Local similarity curves depend on four parameters: the height of the mixed layer (z i ), the depth of the interfacial layer (), and the temperature fluxes at the top of the mixed layer (Q i ) and the surface (Q o). Values of these parameters were inferred from sodar data by using the similarity curve for C T 2 and observations at three points in its profile. The effects of entrainment processes on the profiles of C T 2 and wnear the top of the CBL appeared to be described well by local similarity theory. Inferred estimates of surface temperature flux, however, were underestimated in comparison to fluxes measured by eddy correlation. The measured values of wappeared to be slightly smaller than estimates based on available parmeterizations. These discrepancies might have been caused by experimental error or, more likely, by the distortion of turbulence structure above the site by flow over the nonuniform terrain at the observation site.  相似文献   
56.
Antibiotic resistance of heterotrophic bacteria isolated from a sandy beach in Sopot, at the Southern Baltic Sea coast was determined. The levels of resistance of bacteria to various antibiotics differed considerably. Bacteria inhabiting the middle part of the beach and the dune were most resistant; the least resistant were bacteria isolated from the sea-beach contact zone. Generally, there were no significant differences in antibiotic resistance between pigmented and non-pigmented bacteria. Bacteria isolated from the surface layer of the sand were more resistant to the tested antibiotics than bacteria from the subsurface layers. The majority of bacterial strains were resistant to 3-8 antibiotics. Bacterial resistance to antibiotics was dependent on their chemical structure.  相似文献   
57.
This paper describes the two-phase study of the environmental impact of the SwePol Link submarine electrical energy transfer system between Sweden and Poland. During the first phase (1997–1998), the potential effects of proposed technical solutions for the transmission line and different routes across the Baltic Sea were analysed. During the second phase (1999–2000), studies on environmental and background conditions before cable installation (1999) and studies on the environmental effects after cable system installation (2000) were undertaken. During this phase, underwater TV and video inspection of the bottom, observations of the bottom habitats by scuba-divers, sampling and laboratory analysis of macrozoobenthos and measurements of the earth's magnetic field were conducted.Underwater observations along the cable route indicated that one year after the cable had been laid no mechanical disturbances on the dynamic sandy bottom were visible. Studies of the bottom macrofauna indicated that there had been no significant changes in zoobenthos species composition, abundance or biomass which could have been clearly related to cable installation. Changes in the components of the magnetic field, although significant in the vicinity of the cable itself, did not exceed natural variability at a distance of 20 m.  相似文献   
58.
Theoretical and Applied Climatology - On the basis of temperature observations at 60 meteorological stations in Poland, changes in the indices associated with the presence of extremely high air...  相似文献   
59.
Geo‐questionnaire involves an integration of sketchable maps with questions, aimed at eliciting public preferences and attitudes about land allocation and services. Respondents can link their answers with corresponding locations on a map by marking points or sketching polygon features. Geo‐questionnaires have been used to learn about perceptions and preferences of city residents for specific types of land use, place‐based services, and development projects. This article reports on results of an empirical study, in which an online geo‐questionnaire was designed and implemented to elicit preferences of residents in guiding an urban development plan. Preferences collected in the form of polygon sketches were processed using GIS operations and mapped for visual interpretation. The article focuses on aggregation and analysis of respondent preferences including the analysis of positional and attribute uncertainty. Results of the study show that geo‐questionnaire is a scalable method for eliciting public preferences with a potential for meaningfully informing land use planning.  相似文献   
60.
A number of extensive droughts and destructive floods have occurred in Poland in the last 25 years; hence, projections of low and high river flows are of considerable interest and importance. In the first part of this paper, projections of low and high flows in the rivers of the Vistula and the Odra basins (VOB region), for two future time horizons, are presented. Projections are based on the Soil and Water Assessment Tool (SWAT) hydrological model simulations driven by results of the EURO‐CORDEX experiment under Representative Concentration Pathways 4.5 and 8.5. The VOB region covers most of Poland and parts of five neighboring countries, giving this study an international relevance. In the second part of the paper, a review of projections of low and high flows in rivers in Central and Eastern Europe is presented. Despite a substantial spread of flow projections, the main message of the modelling part is that increases of both low and high flows are dominating. The magnitude of increase of low flow is considerably higher than that of high flow. In other words, future streamflow droughts are projected to be less severe, whereas, in contrast, river floods are projected to increase, which is a challenge for flood risk reduction, water management, and climate change adaptation. There is an overall agreement of our findings for the VOB region with projections of hydrological extremes from large‐scale models forced by EURO‐CORDEX results in the European‐scale studies.  相似文献   
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