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121.
The environmental effects of oil-based drilling mud cuttings have been evaluated using all the data available from monitoring around North Sea platforms. Beneath the platforms making extensive use of oil-based drilling muds the natural sediment is buried by cuttings and the hydrocarbon concentration 250 m from the platforms may be 1000 times background, but the concentration gradient is very steep and background levels are usually reached 2000–3000 m from the platform.The extent of the biological effects appear to be greater from the use of oil-based muds than from water-based muds. Beyond the area of physical smothering the effects of oil-based mud cuttings may be due to organic enrichment or to the toxicity of the aromatic fraction of the oil. Despite the large scale of inputs, in all the fields studied the major deleterious biological effects occurred within 500 m of the platform. Surrounding the area of major impact was a transition zone in which subtle biological effects could be detected as community parameters returned to normal, generally within 400–1000 m.The shape and extent of this zone varied and was largely determined by the current regime and scale of the drilling operation. Elevated hydrocarbon concentrations were detected beyond the areas of biological effects.  相似文献   
122.
Fatal landslides in Europe   总被引:4,自引:3,他引:1  
Landslides are a major hazard causing human and large economic losses worldwide. However, the quantification of fatalities and casualties is highly underestimated and incomplete, thus, the estimation of landslide risk is rather ambitious. Hence, a spatio-temporal distribution of deadly landslides is presented for 27 European countries over the last 20  years (1995–2014). Catastrophic landslides are widely distributed throughout Europe, however, with a great concentration in mountainous areas. In the studied period, a total of 1370 deaths and 784 injuries were reported resulting from 476 landslides. Turkey showed the highest fatalities with 335. An increasing trend of fatal landslides is observed, with a pronounced number of fatalities in the latest period from 2008 to 2014. The latter are mostly triggered by natural extreme events such as storms (i.e., heavy rainfall), earthquakes, and floods and only minor by human activities, such as mining and excavation works. Average economic loss per year in Europe is approximately 4.7 billion Euros. This study serves as baseline information for further risk mapping by integrating deadly landslide locations, local land use data, and will therefore help countries to protect human lives and property.  相似文献   
123.
124.
The stakes for alleviating poverty and avoiding unbridled climate change are inextricably linked. Climate change impacts will slow down and may even reverse trends in poverty reduction. The pathways consistent with global warming of no more than 2?°C require strategies for poverty alleviation to make allowance for the constraint of low-carbon development. Existing climate funds have failed to target poverty alleviation as a high-priority strategy for adaptation or as a component of low-carbon development. This article proposes a funding window as part of the Green Climate Fund in order to foster synergies targeting greater satisfaction of basic needs, while making allowance for adaptation and mitigation. This financial mechanism is based on indicators of the satisfaction of basic needs and could respond to the claims of the developing countries, which see alleviating poverty as the first priority in climate negotiations. It defines a country continuum, given that there are poor people everywhere; all developing countries are therefore eligible with a mechanism of this sort.

Policy relevance

The Intergovernmental Panel on Climate Change (IPCC) calls for substantial emissions reductions and adaptation strategies over the next decades to reduce the high risks of severe impacts of climate change over the 21st century. Industrialized countries and developing countries alike recognize the need to mitigate climate change and to adapt to it. But they face many challenges that lead to an ‘emissions gap’ between an emissions level consistent with the 2?°C increase limit and the voluntary pledges that they have made thus far in the climate negotiations (United Nations Environment Programme. (2014). The Emissions Gap Report 2014. A UNEP synthesis report). In this arena, many developing countries underline that their first domestic priority is the satisfaction of basic needs. In the run-up to the next climate negotiations at the 21st Conference of the Parties (COP 21) in Paris, the proposed poverty-adaptation-mitigation funding window could contribute to alleviate the conflict between development and climate goals in developing countries. In this sense, it could spur developing countries to integrate more ambitious emissions limitations pledges into their Intended Nationally Determined Contributions. This could in turn entice industrialized countries to act similarly. In the end, it could pave the way to an ambitious climate agreement in Paris at COP 21.  相似文献   
125.
Journal of Paleolimnology - Sediment Accumulation Rate (SAR; measured as mm yr?1) and Mass Accumulation Rate (MAR; measured as g cm?2 yr?1) data were collected from...  相似文献   
126.
— Air quality modeling in the marine environment requires a better understanding of air–sea interaction. The behavior of the sea is different from that of the land, particularly with respect to the aerodynamic roughness parameter which changes temporally and spatially as a function of wind-generated wave characteristics. Recent improved understanding in air–sea interaction as applied to topics in air quality modeling are discussed. They include stability characteristics, variation of the wind speed with height, mixing height, standard deviation of crosswind and vertical wind, and the eddy diffusion. These topics are synthesized for scientists and engineers who need to improve the air quality modeling for overwater applications.  相似文献   
127.
The green revolution laid the foundations of modern agriculture, by using science and technology to produce more from same resources. The pesticides contributed to agricultural output in the last decades; however, their use has resulted in environmental pollution, health problems, soil and water contamination and negative impact on biota. The impacts of agricultural activities to the environment depended on the practices adopted during the production process. Measurement tools to assess the impacts of those practices are necessary to improve agricultural systems and must be evaluated in different ecosystems. Different soils, climates and crops impose many phytosanitary arrangements. This complex network and the fact that most of the indicators and measurement tools are developed for temperate climates makes it difficult to quantify the environmental impacts under subtropical regions. The I-Phy index is a predictive indicator that assesses the risks of pesticide usage in agriculture and identifies as to which practices generate the main environmental impacts of pesticides. The objective of this study was to test the suitability of the I-Phy index for subtropical conditions and, if suitable, compare the pesticide risk between two regions. Five crops were assessed under three different cropping systems: no-tillage, minimal tillage and conventional tillage. The I-Phy index was sensitive in both regions and capable of identifying that no-tillage generally presented risks of environmental pollution slightly lower than the other tillage systems. The results of I-Phy index showed that high environmental vulnerability of the fields and the numerous applications of active ingredients with high risks resulted in high risks of general contamination. The application of I-Phy on these two case studies showed the indicator can be useful as a support tool to farmers, research and extension institutions pursuing management practices with lower impact on the environment.  相似文献   
128.
Ceres, a nearly 1000-km diameter body located in the Solar System’s main asteroid belt, has been classified under many categories: planet, comet, asteroid, minor planet and, presently, dwarf planet. No matter what the designation, Ceres has experienced major planetary processes. Its evolution has been controlled by water, making it a most unusual, interesting and accessible inner Solar System object that can inform the evolution of outer Solar System moons and other dwarf planets. Early telescopic observations suggested a hydroxylated mineralogy similar to carbonaceous chondrite meteorites and a size and mass indicating a bulk density that implied a water content of 17?27 wt%. Thermodynamic modeling of Ceres’ evolution indicated that thermal aqueous evolution likely occurred. The Dawn Mission produced a huge increase in our understanding of Ceres, confirming but vastly extending the early knowledge. Dawn, carrying multispectral cameras, a visible-infrared imaging spectrometer and a nuclear spectrometer, orbited Ceres between 2015–2018 (after orbiting Vesta) at a number of different altitudes, ultimately reaching 35 km from the surface at periapsis. Observations of almost the entire surface and gravity field mapping revealed multiple geological and internal features attributed to the effects of water. The surface displays cryovolcanic-like and flow structures, exposed phyllosilicates, carbonates, evaporites and water ice. The subsurface shows partial differentiation, decreasing viscosity with depth, and lateral density heterogeneity. Ceres appears to be geologically active today and possesses liquid water/brine pockets or even an extended liquid layer in the interior, confirming an “Ocean World” designation in today’s vernacular.  相似文献   
129.
Built environment, which includes some major investments in Oman, has been designed based on historical data and do not incorporate the climate change effects. This study estimates potential variations of the hourly annual maximum rainfall (AMR) in the future in Salalah, Oman. Of the five climate models, two were selected based on their ability to simulate local rainfall characteristics. A two-stage downscaling–disaggregation approach was applied. In the first stage, daily rainfall projections in 2040–2059 and 2080–2099 periods from MRI-CGCM3 and CNRM-CM5 models based on two Representative Concentration Pathways (RCP8.5 and RCP4.5) were downscaled to the local daily scale using a stochastic downscaling software (LARS-WG5.5). In the second stage, the stochastically downscaled daily rainfall time series were disaggregated using K-nearest neighbour technique into hourly series. The AMRs, extracted from 20 years of projections for four scenarios and two future periods were then fitted with the generalized extreme value distribution to obtain the rainfall intensity–frequency relationship. These results were compared with a similar relationship developed for the AMRs in baseline period. The results show that the reduction in number of wet days and increases in total rainfall will collectively intensify the future rainfall regime. A marked difference between future and historical intensity–frequency relationships was found with greater changes estimated for higher return periods. Furthermore, intensification of rainfall regime was projected to be stronger towards the end of the twenty-first century.  相似文献   
130.
We use preseismic, coseismic, and postseismic GPS data of the 1999 Chi-Chi earthquake to infer spatio-temporal variation of fault slip and frictional behavior on the Chelungpu fault. The geodetic data shows that coseismic slip during the Chi-Chi earthquake occurred within a patch that was locked in the period preceding the earthquake, and that afterslip occurred dominantly downdip from the ruptured area. To first-order, the observed pattern and the temporal evolution of afterslip is consistent with models of the seismic cycle based on rate-and-state friction. Comparison with the distribution of temperature on the fault derived from thermo-kinematic modeling shows that aseismic slip becomes dominant where temperature is estimated to exceed 200° at depth. This inference is consistent with the temperature induced transition from velocity-weakening to velocity-strengthening friction that is observed in laboratory experiments on quartzo-feldspathic rocks. The time evolution of afterslip is consistent with afterslip being governed by velocity-strengthening frictional sliding. The dependency of friction, μ, on the sliding velocity, V, is estimated to be ${{\partial \mu }/{\partial \, {\rm ln}\, V}} = 8 \times 10^{ - 3}$ . We report an azimuthal difference of about 10–20° between preseismic and postseismic GPS velocities, which we interpret to reflect the very low shear stress on the creeping portion of the décollement beneath the Central Range, of the order of 1–3 MPa, implying a very low friction of about 0.01. This study highlights the importance of temperature and pore pressure in determining fault frictional sliding.  相似文献   
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