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101.
How people privately and collectively adapt to climate risk can affect the costs and benefits of public mitigation policy (e.g., Kyoto); an obvious point often neglected in actual policy making. Herein we use the economic theory of endogenous risk to address this optimal mix of mitigation and adaptation strategies, and examine how increased variability in climate change threats affects this mix. We stress that a better understanding of the cross-links between mitigation and adaptation would potentially make it possible to provide more risk reduction with less wealth. Policies that are formulated without considering the cross-links can unintentionally undermine the effectiveness of public sector policies and programs because of unaddressed conflicts between the strategies. We also discuss the cross-disciplinary lessons to be learned from this literature, and identify important research questions to spur discussion in the next round of inquiry. 相似文献
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Flavio S. Anselmetti Ruth Drescher-Schneider Heinz Furrer Hans Rudolf Graf Sally E. Lowick Frank Preusser Marc A. Riedi 《Swiss Journal of Geoscience》2010,103(3):345-361
A 30 m-deep drill core from a glacially overdeepened trough in Northern Switzerland recovered a ~180 ka old sedimentary succession that provides new insights into the timing and nature of erosion–sedimentation processes in the Swiss lowlands. The luminescence-dated stratigraphic succession starts at the bottom of the core with laminated carbonate-rich lake sediments reflecting deposition in a proglacial lake between ~180 and 130 ka ago (Marine Isotope Stage MIS 6). Anomalies in geotechnical properties and the occurrence of deformation structures suggest temporary ice contact around 140 ka. Up-core, organic content increases in the lake deposits indicating a warming of climate. These sediments are overlain by a peat deposit characterised by pollen assemblages typical of the late Eemian (MIS 5e). An abrupt transition following this interglacial encompasses a likely hiatus and probably marks a sudden lowering of the water level. The peat unit is overlain by deposits of a cold unproductive lake dated to late MIS 5 and MIS 4, which do not show any direct influence from glaciers. An upper peat unit, the so-called «Mammoth peat», previously encountered in construction pits, interrupts this cold lacustrine phase and marks more temperate climatic conditions between 60 and 45 ka (MIS 3). In the upper part of the core, a succession of fluvial and alluvial deposits documents the Late Glacial and Holocene sedimentation in the basin. The sedimentary succession at Wehntal confirms that the glaciation during MIS 6 did not apparently cause the overdeepening of the valley, as the lacustrine basin fill covering most of MIS 6 is still preserved. Consequently, erosion of the basin is most likely linked to an older glaciation. This study shows that new dating techniques combined with palaeoenvironmental interpretations of sediments from such overdeepened troughs provide valuable insights into the past glacial history. 相似文献
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Lee H. Spangler Laura M. Dobeck Kevin S. Repasky Amin R. Nehrir Seth D. Humphries Jamie L. Barr Charlie J. Keith Joseph A. Shaw Joshua H. Rouse Alfred B. Cunningham Sally M. Benson Curtis M. Oldenburg Jennifer L. Lewicki Arthur W. Wells J. Rodney Diehl Brian R. Strazisar Julianna E. Fessenden Thom A. Rahn James E. Amonette Jon L. Barr William L. Pickles James D. Jacobson Eli A. Silver Erin J. Male Henry W. Rauch Kadie S. Gullickson Robert Trautz Yousif Kharaka Jens Birkholzer Lucien Wielopolski 《Environmental Earth Sciences》2010,60(2):227-239
A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented. 相似文献
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Edward Venzke Sally Kuhn Sennert Richard Wunderman Jen Fela 《Bulletin of Volcanology》2011,73(1):113-114
Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network,
vol. 35, no. 6, June 2010 on the Internet at ). Edited by scientists at the Smithsonian, this bulletin includes reports provided by a worldwide network of correspondents.
The reports contain the names and contact information for all sources. Please note that these reports are preliminary and
subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism,
seismic unrest, monitoring data, and field observations. 相似文献
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In this paper, we assess the performance of the catchment model SIMulated CATchment model (SIMCAT), to predict nitrate and soluble reactive phosphorus concentrations against four monitoring regimes with different spatial and temporal sampling frequencies. The Generalised Likelihood Uncertainty Estimation (GLUE) uncertainty framework is used, along with a general sensitivity analysis to understand relative parameter sensitivity. Improvements to model calibration are explored by introducing more detailed process representation using the Integrated Catchments model (INCA) water quality model, driven by the European hydrological predictions for the environment model. The results show how targeted sampling of headwater watercourses upstream of point discharges is essential for calibrating diffuse loads and can exert a strong influence on the whole‐catchment model performance. Further downstream, if the point discharges and loads are accurately represented, then the improvement in the catchment‐scale model performance is relatively small as more calibration points are added or frequency is increased. The higher‐order, dynamic model integrated catchments model of phosphorus dynamics, which incorporates sediment and biotic interaction, resulted in improved whole‐catchment performance over SIMCAT, although there are still large epistemic uncertainties from land‐phase export coefficients and runoff. However, the very large sampling errors in routine monitoring make it difficult to invest confidence in the modelling, especially because we know phosphorous transport to be very episodic and driven by high flow conditions for which there are few samples. The environmental modelling community seems to have been stuck in this position for some time, and whilst it is useful to use an uncertainty framework to highlight these issues, it has not widely been adopted, perhaps because there is no clear mechanism to allow uncertainties to influence investment decisions. This raises the question as to whether it might better place a cost on uncertainty and use this to drive more data collection or improved models, before making investment decisions concerning, for example, mitigation strategies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Patterns,puzzles and people: implementing hydrologic synthesis 总被引:2,自引:0,他引:2
Sally E. Thompson C. J. Harman R. Schumer J. S. Wilson N. B. Basu P. D. Brooks S. D. Donner M. A. Hassan A. I. Packman P. S. C. Rao P. A. Troch M. Sivapalan 《水文研究》2011,25(20):3256-3266
There have been several calls made for hydrologic synthesis research: namely activities which unify diverse data sources across sites, scales and disciplines to uncover new connections and to promote a holistic understanding of water science. This paper draws on the NSF‐funded Hydrological Synthesis Project (HSP) run by the University of Illinois at Urbana‐Champaign to elucidate mechanisms, benefits and challenges of implementing hydrologic synthesis research from the perspectives of participants in a pilot research study. Two broadly different mechanisms of implementing synthesis were adopted in the HSP: 6‐week Summer Institutes in which Ph.D. students conducted team‐based research under the guidance of faculty mentors, and focused workshops which disseminated knowledge and shared experiences between scientists at many different career levels. The Summer Institutes were a test bed in which new ideas could be explored, assisted students in developing a wide range of skills, and were highly productive, but posed challenges for mentors and students because the ‘new’ research topics initiated during the Institutes' programmes needed to be completed in competition with students' ongoing Ph.D. research or mentor's existing research programs. The workshop‐based model circumvented this conflict and was also highly productive, but did not offer the same opportunity to experiment with new ideas as part of the synthesis research. Leadership, trust, flexibility and long gestation times were all important to bringing synthesis research to a positive resolution. Funding models that embrace the exploratory aspects of synthesis and provide adequate support to mentors and students over these long timescales would facilitate future hydrologic synthesis research. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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