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31.
Many actions to reduce GHG emissions have wider impacts on health, the economy, and the environment, beyond their role in mitigating climate change. These ancillary impacts can be positive (co-benefits) or negative (conflicts). This article presents the first quantitative review of the wider impacts on health and the environment likely to arise from action to meet the UK's legally-binding carbon budgets. Impacts were assessed for climate measures directed at power generation, energy use in buildings, and industry, transport, and agriculture. The study considered a wide range of health and environmental impacts including air pollution, noise, the upstream impacts of fuel extraction, and the lifestyle benefits of active travel. It was not possible to quantify all impacts, but for those that were monetized the co-benefits of climate action (i.e. excluding climate benefits) significantly outweigh the negative impacts, with a net present value of more than £85 billion from 2008 to 2030. Substantial benefits arise from reduced congestion, pollution, noise, and road accidents as a result of avoided journeys. There is also a large health benefit as a result of increased exercise from walking and cycling instead of driving. Awareness of these benefits could strengthen the case for more ambitious climate mitigation action.

Policy relevance

This article demonstrates that actions to mitigate GHG emissions have significant wider benefits for health and the environment. Including these impacts in cost–benefit analysis would strengthen the case for the UK (and similar countries) to set ambitious emissions reduction targets. Understanding co-benefits and trade-offs will also improve coordination across policy areas and cut costs. In addition, co-benefits such as air quality improvements are often immediate and local, whereas climate benefits may occur on a longer timescale and mainly in a distant region, as well as being harder to demonstrate. Dissemination of the benefits, along with better anticipation of trade-offs, could therefore boost public support for climate action.  相似文献   

32.
The fluorspar deposites described are located within the permotriasic basin of Western Asturias/Northern Spain. The block-faulted basin is bordered in the south by the Cantabrian Mountainrange, folded in Hercynian times. The fluorspar deposites overlie the strata of this paleozoic base and the fluorspar-layers dip gently to the North at 10 to 15?. They are related to the angular unconformity between the mostly eroded Paleozoic rocks and the overlying, mainly red, Permotriasic sediments. Volcanic rocks apear only in few places, where they are intercalating more ore less the upper parts of triasic strata, reddish shales of “Keuper” age. The occurrences fluorspar-layers are found mainly in the uneroded areas where the basal Permotriasic is still preserved on the old Permian land surface, underlain preserved on the old Permian land surface, underlain mostly by Devonian and lower Carboniferous limestones, marls and shales. A special rock type, a breccia between the foulded Paleozoic base and the unfolded Permotriasic sediments forms a marker horizon, thought to have originated from the fracturing of the underlaying Paleozoic rocks. The genesis of fluorspar and breccia is thought to be connected with the formation of a peneplain-like land surface and its repetated uplift and depression, i. e. repeated flooding by sea and subsequent emergence. Light-grey to reddisch sand- and siltstones as well as small pebble conglomerates were deposited in erosion channels and karst holes, sometimes extending through the breccia down into the massiv lower Carboniferous and Devonian base. It is in these sediments, that the fluorspar is found to produce dispersed or in massiv form sheet-like and flat-lying bodies as well as channel-like, occurrences. In areas of strong post, Permian tectonic movements the stratabound mineralisation were sometimes mobilized to form dike-like deposites. The morphological and petrological structure, e. g. the complete lack of primary zoning even in dike-like deposites, and the geological situation as a whole contradict the opinion of G.Einecke (1956) that these fluorspar deposites originated from hydrothermal solutions, emanating from plutonic or volcanic rocks. Geochemical investigations of soil samples and drill cores from Paleozoic rocks point to the origin of fluorine from Devonian and Carboniferous, rich in organisms (Coal-strata) and consisting of shales marls and limestones (or even older rocks) which were eroded and redeposited in Permian times.  相似文献   
33.
The Macquarie Arc of New South Wales hosts several major Au and Cu deposits. We present new Pb isotope results for Cadia, the Copper Hill, Little Copper Hill and Cowal deposits, along with data from the CSIRO database. The results generally plot close to established mantle growth curves and are similar to oceanic basalts. Data for individual deposits mostly have Pb model ages consistent with independent age constraints on mineralization. Intrusions associated with the Early Silurian mineralization at Cadia and Goonumbla have narrow and distinct Pb isotope signatures that we interpret to be the result of partial melting of already LILE-enriched mantle-like sources. The data suggest that deposits of the Macquarie Arc derived Pb from one or more long-lived mantle-like Pb isotope reservoirs without significant contributions of crustal Pb prior to the Benambran Orogeny.Data for the Copper Hill deposits includes unradiogenic, possibly old Pb and supports previous workers who suggested that old MORB-like basalts may occur at depth in the area. The Peak Hill deposit has the most unradiogenic signature and has the lowest 208Pb/204Pb and 207Pb/204Pb. These signatures closely match Cambrian MORB-like basalts in the Koonenberry Belt and are unlike Cambrian mafic rocks in Victoria. Similar rocks could form part of the substrate to other parts of the Macquarie Arc.  相似文献   
34.
Supraglacial rivers on the Greenland Ice Sheet (GrIS) transport large volumes of surface meltwater toward the ocean, yet have received relatively little direct research. This study presents field observations of channel width, depth, velocity, and water surface slope for nine supraglacial channels on the south‐western GrIS collected between July 23 and August 20, 2012. Field sites are located up to 74 km inland and span 494–1485 m elevation, and contain measured discharges larger than any previous in situ study: from 0.006 to 23.12 m3/s in channels 0.20 to 20.62 m wide. All channels were deeply incised with near vertical banks, and hydraulic geometry results indicate that supraglacial channels primarily accommodate greater discharges by increasing velocity. Smaller streams had steeper water surface slopes (0.74–8.83%) than typical in terrestrial settings, yielding correspondingly high velocities (0.40–2.60 m/s) and Froude numbers (0.45–3.11) with supercritical flow observed in 54% of measurements. Derived Manning's n values were larger and more variable than anticipated from channels of uniform substrate, ranging from 0.009 to 0.154 with a mean value of 0.035 ± 0.027 despite the absence of sediment, debris, or other roughness elements. Ubiquitous micro‐depressions in shallow sections of the channel bed may explain some of these roughness values. However, we find that other, unobserved sources of flow resistance likely contributed to these elevated Manning's n values: future work should explicitly consider additional sources of flow resistance beyond bed roughness in supraglacial channels. We conclude that hydraulic modeling for these channels must allow for both subcritical and supercritical flow, and most importantly must refrain from assuming that all ice‐substrate channels exhibit similar hydraulic behavior, especially for Froude numbers and Manning's n. Finally, this study highlights that further theoretical and empirical work on supraglacial channel hydraulics is necessary before broad scale understanding of ice sheet hydrology can be achieved. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
35.
36.
K-feldspar from the late Miocene Capoas Granite on Palawan in The Philippines appears to contain highly retentive diffusion domains that are closed to argon diffusion at near-solidus temperatures during cooling of this ~7 km-diameter pluton. This is an important result, for K-feldspar is commonly considered not retentive in terms of its ability to retain argon. Closure temperatures for argon diffusion in K-feldspars are routinely claimed to be in the range ~150–400°C but the release of 39Ar from irradiated K-feldspar during furnace step-heating experiments in vacuo yields Arrhenius data that imply the existence of highly retentive core domains, with inferred closure temperatures that can exceed ~500–700°C. These high closure temperatures from the Capoas Granite K-feldspar are consistent with the coincidence of 40Ar/39Ar ages with U–Pb zircon ages at ca 13.5 ± 0.2 Ma. The cooling rate then accelerated, but the rate of change had considerably slowed by ca 12 Ma. Low-temperature (U–Th)/He thermochronology shows that the cooling rate once again accelerated at ca 11 Ma, perhaps owing to renewed tectonic activity.  相似文献   
37.
A 4-week laboratory experiment investigated the behaviour (survival and bioirrigation) and impact of the invasive polychaetes Marenzelleria viridis, M. neglecta and M. arctia on sediment-water solutes exchange, porewater chemistry, and Fe and P interactions in high-salinity sandy sediment (HSS) and low-salinity muddy sediment (LSM) from the Baltic Sea. M. viridis showed deep burrowing with efficient bioirrigation (11 L m?2 day?1) and high survival (71%) in HSS, while M. arctia exhibited shallow burrowing with high bioirrigation (12 L m?2 day?1) and survival (88%) in LSM. M. neglecta behaved poorly in both ecological settings (bioirrigation, 5–6 L m?2 day?1; survival, 21–44%). The deep M. viridis bioirrigation enhanced total microbial CO2 (TCO2) production in HSS by 175% with a net efflux of NH4+ and PO43?, at rates 3- to 27-fold higher than for the other species. Although the shallow and intense bioirrigation of M. arctia in LSM stimulated microbial TCO2 production to some extent (61% enhancement), the nutrient fluxes close to zero indicate that it effectively prevented the P release. Porewater Fe:PO43? ratios revealed that the oxidizing effect of M. arctia bioirrigation increased the PO43? adsorption capacity of LSM twofold relative to defaunated controls while no buffering of PO43? was detected in M. viridis HSS treatment. Therefore, the different behaviour of the three species in various environments and the sharp contrast between M. viridis and M. arctia effects on C, N and P cycling must be considered carefully when the ecological role of Marenzelleria species in the Baltic Sea is evaluated.  相似文献   
38.
Interstellar H2O and OH masers associated with massive star-forming regions can be classified into three morphological types: isolated H2O masers; isolated OH masers; and spatially overlapping OH/H2O maser groups. In a large sample of star-forming regions the total number of maser groups of each type is approximately equal. In order to account for these statistics we propose a pumping scheme based on a broadband radiative pump which produces inverted populations of both OH and H2O masers by a process involving predissociation and dissociation of H2O. This scheme overcomes some drawbacks of earlier radiative pumping models, and may account for the association of OH and H2O masers in massive star forming regions.  相似文献   
39.
Releases of halocarbons into the atmosphere over the last 50 years are among the factors that have contributed to changes in the Earth’s climate since pre-industrial times. Their individual and collective potential to contribute directly to surface climate change is usually gauged through calculation of their radiative efficiency, radiative forcing, and/or Global Warming Potential (GWP). For those halocarbons that contain chlorine and bromine, indirect effects on temperature via ozone layer depletion represent another way in which these gases affect climate. Further, halocarbons can also affect the temperature in the stratosphere. In this paper, we use a narrow-band radiative transfer model together with a range of climate models to examine the role of these gases on atmospheric temperatures in the stratosphere and troposphere. We evaluate in detail the halocarbon contributions to temperature changes at the tropical tropopause, and find that they have contributed a significant warming of ~0.4 K over the last 50 years, dominating the effect of the other well-mixed greenhouse gases at these levels. The fact that observed tropical temperatures have not warmed strongly suggests that other mechanisms may be countering this effect. In a climate model this warming of the tropopause layer is found to lead to a 6% smaller climate sensitivity for halocarbons on a globally averaged basis, compared to that for carbon dioxide changes. Using recent observations together with scenarios we also assess their past and predicted future direct and indirect roles on the evolution of surface temperature. We find that the indirect effect of stratospheric ozone depletion could have offset up to approximately half of the predicted past increases in surface temperature that would otherwise have occurred as a result of the direct effect of halocarbons. However, as ozone will likely recover in the next few decades, a slightly faster rate of warming should be expected from the net effect of halocarbons, and we find that together halocarbons could bring forward next century’s expected warming by ~20 years if future emissions projections are realized. In both the troposphere and stratosphere CFC-12 contributes most to the past temperature changes and the emissions projection considered suggest that HFC-134a could contribute most of the warming over the coming century.  相似文献   
40.
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