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81.
The climate tourism potential of a region can be described by methods used in human biometeorology and applied climatology. Frequency analyses based on complex thermal bioclimatic indices (e.g. physiologically equivalent temperature) and diagrams of precipitation patterns based on thresholds offer new approaches of visualisation. An integral approach for tourism climatologic analyses is provided by the climate?Ctourism/transfer?Cinformation?Cscheme that also bases on frequency distributions of relevant factors and parameters which are important for a destination. The knowledge about the vertical variability of tourism climatologic factors is of high importance because of the several kinds of tourism activities affected by weather. The same holds for a quantification of extreme events like heat waves because of their possible effects on health and recreation over a year's course. The results show that the vertical gradient of bioclimatic and tourism-related parameters can be of value when developing strategies of adaption to climate change.  相似文献   
82.
We present the first statistical analysis of 27 Ultraviolet Optical Telescope (UVOT) optical/ultraviolet light curves of gamma-ray burst (GRB) afterglows. We have found, through analysis of the light curves in the observer's frame, that a significant fraction rise in the first 500 s after the GRB trigger, all light curves decay after 500 s, typically as a power law with a relatively narrow distribution of decay indices, and the brightest optical afterglows tend to decay the quickest. We find that the rise could be either produced physically by the start of the forward shock, when the jet begins to plough into the external medium, or geometrically where an off-axis observer sees a rising light curve as an increasing amount of emission enters the observers line of sight, which occurs as the jet slows. We find that at 99.8 per cent confidence, there is a correlation, in the observed frame, between the apparent magnitude of the light curves at 400 s and the rate of decay after 500 s. However, in the rest frame, a Spearman rank test shows only a weak correlation of low statistical significance between luminosity and decay rate. A correlation should be expected if the afterglows were produced by off-axis jets, suggesting that the jet is viewed from within the half-opening angle θ or within a core of a uniform energy density  θc  . We also produced logarithmic luminosity distributions for three rest-frame epochs. We find no evidence for bimodality in any of the distributions. Finally, we compare our sample of UVOT light curves with the X-ray Telescope (XRT) light-curve canonical model. The range in decay indices seen in UVOT light curves at any epoch is most similar to the range in decay of the shallow decay segment of the XRT canonical model. However, in the XRT canonical model, there is no indication of the rising behaviour observed in the UVOT light curves.  相似文献   
83.
Fluctuations of glaciers during the 20th century in Garibaldi Provincial Park, in the southern Coast Mountains of British Columbia, were reconstructed from historical documents, aerial photographs, and fieldwork. Over 505 km2, or 26%, of the park, was covered by glacier ice at the beginning of the 18th century. Ice cover decreased to 297 km2 by 1987–1988 and to 245 km2 (49% of the early 18th century value) by 2005. Glacier recession was greatest between the 1920s and 1950s, with typical frontal retreat rates of 30 m/a. Many glaciers advanced between the 1960s and 1970s, but all glaciers retreated over the last 20 years. Times of glacier recession coincide with warm and relatively dry periods, whereas advances occurred during relatively cold periods. Rapid recession between 1925 and 1946, and since 1977, coincided with the positive phase of the Pacific Decadal Oscillation (PDO), whereas glaciers advanced during its negative phase (1890–1924 and 1947–1976). The record of 20th century glacier fluctuations in Garibaldi Park is similar to that in southern Europe, South America, and New Zealand, suggesting a common, global climatic cause. We conclude that global temperature change in the 20th century explains much of the behaviour of glaciers in Garibaldi Park and elsewhere.  相似文献   
84.
D. Markovic  M. Koch 《水文研究》2014,28(4):2202-2211
Long‐term variations and temporal scaling of mean monthly time series of river flow, precipitation, temperature, relative humidity, air pressure, duration of bright sunshine, degree of cloud cover, short wave radiation, wind speed and potential evaporation within or in vicinity of the German part of the Elbe River Basin are analyzed. Statistically significant correlations between the 2–15 year scale‐averaged wavelet spectra of the hydroclimatic variables and the North Atlantic Oscillation‐ and Arctic Oscillation index are found which suggests that such long‐term patterns in hydroclimatic time series are externally forced. The Hurst parameter estimates (H) based on the Detrended Fluctuation Analysis (DFA) indicate persistence for discharge, precipitation, wind speed, air pressure and the degree of cloud cover, all having an annual cycle and a broad low‐frequency distribution. Also, DFA H parameter estimates are higher for discharge than for precipitation. The major long‐term quasi‐periodic variability modes of precipitation detected using Singular Spectrum Analysis coincide with those detected in the discharge time series. Upon subtraction of these low‐frequency quasi‐periodic modes, the DFA H parameter estimates suggest absence of the persistence for both precipitation and discharge. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
85.
Climate change impact assessments form the basis for the development of suitable climate change adaptation strategies. For this purpose, ensembles consisting of stepwise coupled models are generally used [emission scenario → global circulation model → downscaling approach (DA) → bias correction → impact model (hydrological model)], in which every item is affected by considerable uncertainty. The aim of the current study is (1) to analyse the uncertainty related to the choice of the DA as well as the hydrological model and its parameterization and (2) to evaluate the vulnerability of the studied catchment, a subcatchment of the highly anthropogenically impacted Spree River catchment, to hydrological change. Four different DAs are used to drive four different model configurations of two conceptually different hydrological models (Water Balance Simulation Model developed at ETH Zürich and HBV‐light). In total, 452 simulations are carried out. The results show that all simulations compute an increase in air temperature and potential evapotranspiration. For precipitation, runoff and actual evapotranspiration, opposing trends are computed depending on the DA used to drive the hydrological models. Overall, the largest source of uncertainty can be attributed to the choice of the DA, especially regarding whether it is statistical or dynamical. The choice of the hydrological model and its parameterization is of less importance when long‐term mean annual changes are compared. The large bandwidth at the end of the modelling chain may exacerbate the formulation of suitable climate change adaption strategies on the regional scale. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
86.
There is a growing interest in the use of geoinformation in government decision‐making. Studies on the usability of geological information, which is one type of geoinformation, have however been scarce in the literature. A system built for an efficient organization may, therefore, not be catering to the needs of the individual user and understanding the perceived barriers to using geological information should be an important goal of geodata implementation. The objectives of this article are to: (1) investigate whether the analyses of user patterns are improved by considering an interrelated estimation with two types of geoinformation, and (2) explore whether there are gender differences in how peer advice affects the use of geoinformation. The data were collected in 2014 through a web survey, and the sample consisted of 390 women and 287 men working in Swedish municipalities. The results indicates a more accurate prediction pattern when a secondary geoinformation decision was included, thus suggesting that different types of geoinformation should be jointly analyzed. The officials tend to use both types of geoinformation, alluding to a demand for combined geoinformation products among the target population. Finally, there is evidence of women's decision to use geoinformation being affected by peer advice.  相似文献   
87.
Zusammenfassung Auf Grund von Registrierungen an eng benachbarten Stationen, die im obersten Salzachtal im Land Salzburg in verschiedenen Höhenlagen zwischen Tal (900 m) und Kammhöhe (2000 m) des begleitenden Gebirgszuges gelegen waren, werden Tagesgänge der relativen Feuchtigkeit, des Dampfdrucks und der spezifischen Feuchtigkeit für Schönwettertage abgeleitet (Tab. 2). Im Vergleich dieser Stationen zeigt sich der Übergang der Form der Tagesgänge der relativen Feuchtigkeit (Abb. 2 und 3) und des Dampfdrucks (Abb. 4) von dem Typ der Niederung zu dem der Bergstationen. Der Einfluß der Konvektion und der über die feuchten Hänge streichenden Hangaufwinde auf diese Umgestaltung der Tagesgänge wird für die einzelnen Jahreszeiten quantitativ nachgewiesen und diskutiert.
Summary Using records taken at closely neighbouring stations situated in the uppermost valley of the Salzach in the province of Salzburg at different levels between the valley-bottom (900 m) and the height of the adjacent mountain-ridge (2000 m) the diurnal variation of relative humidity, vapor pressure and specific humidity are derived for fair weather days (Tab. 2). The comparison of these stations shows the transition of the diurnal variation of relative humidity (Fig. 2 and 3) and vapor pressure (Fig. 4) from the ground type to that of the mountain stations. The influence of the convection and of the ascending currents passing over the moist slopes upon this modification of the diurnal variation is quantitatively proved and discussed for the different seasons.

Résumé Sur la base d'enregistrements à des stations étroitement voisines situées dans la vallée la plus haute de la Salzach en province de Salzbourg à des niveaux differents entre la vallée (900 m) et l'altitude de la crête de la chaine adjacente de montagnes (2000 m) les variations diurnes de l'humidité relative, de la pression de vapeur et de l'humidité spécifique sont derivées pour les jours de beau temps (Tab. 2). En comparaison de cettes stations la transition de la forme des variations diurnes de l'humidité relative (Fig. 2 et 3) et de la pression de vapeur (Fig. 4) se présente du type de vallée à celui des stations de montagne. L'influence de la convection et des courants ascendants passant sur les pentes humides sur la transformation des variations diurnes est démontrée quantitativement et discutée.


Mit 4 Textabbildungen.  相似文献   
88.
89.
State governments in the United States are well placed to identify opportunities for mitigation and the needs for adaptation to climate change. However, the cost of these efforts can have important implications for budgets that already face pressures from diverse areas such as unfunded pensions and growing health care costs. In this work, the current level of spending on climate-related activities at the state level are evaluated and policy recommendations are developed to improve financial management practices as they relate to climate risk. An examination of state budgets reveals that climate mitigation and adaptation activities represent less than 1% of spending in most states. The data collection highlights the obstacles to collecting accurate spending data and the lack of budgetary and accounting procedures in place. More importantly, the difficulty in benchmarking these activities poses challenges for the analysis of state-level policies as well as planning and modelling future climate-related spending. Other policy contexts, including public pensions and infrastructure, can provide guidance on budgetary and accounting tools that may help states prepare for and more efficiently manage climate-related expenditures.

Key policy insights

  • Climate change mitigation and adaptation will require substantial investments across many levels of government on a wide range of activities.

  • Currently, US states are not clearly demarcating climate expenditures, hindering the identification of climate-related budgetary risks.

  • In the absence of guidelines, these longer term fiscal outlays may remain chronically underfunded in favour of more near-term spending priorities.

  • Establishing appropriate financial management and data collection practices is important for more sophisticated cost-effectiveness and policy analyses.

  相似文献   
90.
Although agriculture could contribute substantially to European emission reductions, its mitigation potential lies untapped and dormant. Market-based instruments could be pivotal in incentivizing cost-effective abatement. However, sector specificities in transaction costs, leakage risks and distributional impacts impede its implementation. The significance of such barriers critically hinges on the dimensions of policy design. This article synthesizes the work on emissions pricing in agriculture together with the literature on the design of market-based instruments. To structure the discussion, an options space is suggested to map policy options, focusing on three key dimensions of policy design. More specifically, it examines the role of policy coverage, instruments and transfers to farmers in overcoming the barriers. First, the results show that a significant proportion of agricultural emissions and mitigation potential could be covered by a policy targeting large farms and few emission sources, thereby reducing transaction costs. Second, whether an instrument is voluntary or mandatory influences distributional outcomes and leakage. Voluntary instruments can mitigate distributional concerns and leakage risks but can lead to subsidy lock-in and carbon price distortion. Third, the impact on transfers resulting from the interaction of the Common Agricultural Policy (CAP) with emissions pricing will play a key role in shaping political feasibility and has so far been underappreciated.

POLICY RELEVANCE

Following the 2015 Paris Agreement, European climate policy is at a crossroads. Achieving cost-effectively the 2030 and 2050 European targets requires all sectors to reduce their emissions. Yet, the cornerstone of European climate policy, the European Union Emissions Trading System (EU ETS), covers only about half of European emissions. Major sectors have been so far largely exempted from carbon pricing, in particular transport and agriculture. While transport has been increasingly under the spotlight as a possible candidate for an EU ETS sectoral expansion, policy discussions on pricing agricultural emissions have been virtually absent. This article attempts to fill this gap by investigating options for market-based instruments to reduce agricultural emissions while taking barriers to implementation into account.  相似文献   

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