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排序方式: 共有610条查询结果,搜索用时 31 毫秒
71.
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73.
VOCs in Ground Water Influenced by Large Scale Withdrawals 总被引:1,自引:0,他引:1
74.
Robert A. Watson Pedro Carreira Kieran Cleary Rod D. Davies Richard J. Davis Clive Dickinson Keith Grainge † Carlos M. Gutiérrez Michael P. Hobson Michael E. Jones Rüdiger Kneissl Anthony Lasenby Klaus Maisinger Guy G. Pooley Rafael Rebolo José Alberto Rubiño-Martin ‡ Ben Rusholme § Richard D. E. Saunders Richard Savage Paul F. Scott Ane Slosar Pedro J. Sosa Molina Angela C. Taylor David Titterington Elizabeth Waldram Althea Wilkinson 《Monthly notices of the Royal Astronomical Society》2003,341(4):1057-1065
75.
Measurements of phytoplankton distribution and production, and zooplankton abundance and biomass were made during the summer of 1979 along several shelf-slope transects in the Mid-Atlantic Bight. At the shelf-break, macrozooplankton (>200 μm) grazing was estimated to be sufficient to remove a substantial proportion of daily phytoplankton production. In contrast, on the shelf and in slope waters, where ciliates were abundant, estimates of macrozooplankton grazing indicated a consumption rate less than 15% of the daily primary production. Ciliate grazing, even at non-maximum rates, potentially could have consumed the entire daily primary production in all areas sampled. The findings indicate that the nature of the heterotrophic community is spatially variable in offshore waters even during summer conditions and could influence not only trophodynamic pathways but perhaps nutrient regeneration and recycling. This would be an important consideration in evaluating the fate of particle-bound chemcial species in the water column since fecal pellet producing zooplankton would affect rates of removal and sedimentation in a different manner than ciliates which produce non-compacted digestive debris. 相似文献
76.
Francis Joseph Turk Byung-Ju Sohn Hyun-Jong Oh Elizabeth E. Ebert Vincenzo Levizzani Eric A. Smith 《Meteorology and Atmospheric Physics》2009,105(1-2):99-108
In order to properly utilize remotely sensed precipitation estimates in hydrometeorological applications, knowledge of the accuracy of the estimates are needed. However, relatively few ground validation networks operate with the necessary spatial density and time-resolution required for validation of high-resolution precipitation products (HRPP) generated at fine space and time scales (e.g., hourly accumulations produced on a 0.25° spatial scale). In this article, we examine over-land validation statistics for an operationally designed, meteorological satellite-based global rainfall analysis that blends intermittent passive microwave-derived rainfall estimates aboard a variety of low Earth-orbiting satellite platforms with sub-hourly time sampling capabilities of visible and infrared imagers aboard operational geostationary platforms. The validation dataset is comprised of raingauge data collected from the dense, nearly homogeneous, 1-min reporting Automated Weather Station (network of the Korean Meteorological Administration during the June to August 2000 summer monsoon season. The space-time RMS error, mean bias, and correlation matrices were computed using various time windows for the gauge averaging, centered about the satellite observation time. For ±10 min time window, a correlation of 0.6 was achieved at 0.1° spatial scale by averaging more than 3 days; coarsening the spatial scale to 1.8° produced the same correlation by averaging over 1 h. Finer than approximately 24-h and 1° time and space scales, respectively, a rapid decay of the error statistics was obtained by trading-off either spatial or time resolution. Beyond a daily time scale, the blended estimates were nearly unbiased and with an RMS error of no worse than 1 mm day?1. 相似文献
77.
Lara C. Whitely Binder Jennifer Krencicki Barcelos Derek B. Booth Meriel Darzen Marketa McGuire Elsner Richard Fenske Thomas F. Graham Alan F. Hamlet John Hodges-Howell J. Elizabeth Jackson Catherine Karr Patrick W. Keys Jeremy S. Littell Nathan Mantua Jennifer Marlow Don McKenzie Michael Robinson-Dorn Eric A. Rosenberg Claudio O. Stöckle Julie A. Vano 《Climatic change》2010,102(1-2):351-376
Climate change is expected to bring potentially significant changes to Washington State’s natural, institutional, cultural, and economic landscape. Addressing climate change impacts will require a sustained commitment to integrating climate information into the day-to-day governance and management of infrastructure, programs, and services that may be affected by climate change. This paper discusses fundamental concepts for planning for climate change and identifies options for adapting to the climate impacts evaluated in the Washington Climate Change Impacts Assessment. Additionally, the paper highlights potential avenues for increasing flexibility in the policies and regulations used to govern human and natural systems in Washington. 相似文献
78.
J. Elizabeth Jackson Michael G. Yost Catherine Karr Cole Fitzpatrick Brian K. Lamb Serena H. Chung Jack Chen Jeremy Avise Roger A. Rosenblatt Richard A. Fenske 《Climatic change》2010,102(1-2):159-186
Illness and mortality related to heat and worsening air quality are core public health concerns associated with climate change projections. We examined the historical relationship between age- and cause-specific mortality rates from 1980 through 2006 and heat events at the 99th percentile of humidex values in the historic period from January 1, 1970 to December 31, 2006 in the greater Seattle area (King, Pierce and Snohomish counties), Spokane County, the Tri-Cities (Benton and Franklin counties) and Yakima County; the relative risks of mortality during heat events were applied to population and climate projections for Washington State to calculate number of deaths above the baseline (1980–2006) expected during projected heat events in 2025, 2045 and 2085. Three different warming scenarios were used in the analysis. Relative risks for the greater Seattle area showed a significant dose-response relationship between heat event duration and daily mortality rates for non-traumatic deaths for persons ages 45 and above, typically peaking at four days of exposure to humidex values above the 99th percentile. The largest number of projected excess deaths in all years and scenarios for the Seattle region was found for age 65 and above. Under the middle warming scenario, this age group is expected to have 96, 148 and 266 excess deaths from all non-traumatic causes in 2025, 2045 and 2085, respectively. We also examined projected excess deaths due to ground-level ozone concentrations at mid century (2045–2054) in King and Spokane counties. Current (1997–2006) ozone measurements and mid-twenty-first century ozone projections were coupled with dose-response data from the scientific literature to produce estimates overall and cardiopulmonary mortality. Daily maximum 8-h ozone concentrations are forecasted to be 16–28% higher in the mid twenty-first century compared to the recent decade of 1997–2006. By mid-century in King County the non-traumatic mortality rate related to ozone was projected to increase from baseline (0.026 per 100,000; 95% confidence interval 0.013–0.038) to 0.033 (95% CI 0.017–0.049). For the same health outcome in Spokane County, the baseline period rate of 0.058 (95% CI 0.030–0.085) was estimated increase to 0.068 (95% CI 0.035–0.100) by mid-century. The cardiopulmonary death rate per 100,000 due to ozone was estimated to increase from 0.011 (95% CI 0.005–0.017) to 0.015 (0.007–0.022) in King County, and from 0.027 (95% CI 0.013–0.042) to 0.032 (95% CI 0.015–0.049) in Spokane County. Public health interventions aimed at protecting Washington’s population from excessive heat and increased ozone concentrations will become increasingly important for preventing deaths, especially among older adults. Furthermore, heat and air quality related illnesses that do not result in death, but are serious nevertheless, may be reduced by the same measures. 相似文献
79.
This study builds on an earlier analysis of resilience of India and Indian states to climate change. The previous study (Brenkert and Malone, Clim Change 72:57–102, 2005) assessed current resilience; this research uses the Vulnerability–Resilience Indicators Model (VRIM) to project resilience to 2095 and to perform an uncertainty analysis on the deterministic results. Projections utilized two SRES-based scenarios, one with fast-and-high growth, one with delayed growth. A detailed comparison of two states, the Punjab and Orissa, points to the kinds of insights that can be obtained using the VRIM. The scenarios differ most significantly in the timing of the uncertainty in economic prosperity (represented by GDP per capita) as a major factor in explaining the uncertainty in the resilience index. In the fast-and-high growth scenario the states differ most markedly regarding the role of ecosystem sensitivity, land use and water availability. The uncertainty analysis shows, for example, that resilience in the Punjab might be enhanced, especially in the delayed growth scenario, if early attention is paid to the impact of ecosystems sensitivity on environmental well-being of the state. By the same token, later in the century land-use pressures might be avoided if land is managed through intensification rather than extensification of agricultural land. Thus, this methodology illustrates how a policy maker can be informed about where to focus attention on specific issues, by understanding the potential changes at a specific location and time—and, thus, what might yield desired outcomes. Model results can point to further analyses of the potential for resilience-building. 相似文献
80.