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Emissions from the production of iron and steel could constitute a significant share of a 2°C global emissions budget (around 19% under the IEA 2DS scenario). They need to be reduced, and this could be difficult under nationally based climate policy approaches. We compare a new set of nationally based modelling (the Deep Decarbonization Pathways Project) with best practice and technical limit benchmarks for iron and steel and cement emissions. We find that 2050 emissions from iron and steel and cement production represent an average 0.28?tCO2 per capita in nationally based modelling results, very close to the technical limit benchmark of 0.21?tCO2 per capita, and over 2.5 times lower than the best practice benchmark of 0.72?tCO2 per capita. This suggests that national projections may be overly optimistic about achievable emissions reductions in the absence of global carbon pricing and an international research and development effort to develop low emissions technologies for emissions-intensive products. We also find that equal per capita emissions targets, often the basis of proposals for how global emissions budgets should be allocated, would be inadequate without global emissions trading. These results show that a nationally based global climate policy framework, as has been confirmed in the Paris Agreement, could lead to risks of overshooting global emissions targets for some countries and carbon leakage. Tailored approaches such as border taxes, sectoral emissions trading or carbon taxes, and consumption-based carbon pricing can help, but each faces difficulties. Ultimately, global efforts are needed to improve technology and material efficiency in emissions-intensive commodities manufacturing and use. Those efforts could be supported by technology standards and a globally coordinated R&D effort, and strengthened by the adoption of global emissions budgets for emissions-intensive traded goods.Policy relevanceThis article presents new empirical findings on global iron and steel and cement production in a low-carbon world economy, demonstrates the risks associated with a nationally based global climate policy framework as has been confirmed in the Paris Agreement, and analyses policy options to deal with those risks. 相似文献
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The effect of plant species on erosion processes may be decisive for long‐term soil protection in degraded ecosystems. The identification of functional effect traits that predict species ability for erosion control would be of great interest for ecological restoration purposes. Flume experiments were carried out to investigate the effect of the root systems of three species having contrasted ecological requirements from eroded marly lands of the French Southern Alps [i.e. Robinia pseudo acacia (tree), Pinus nigra austriaca (tree) and Achnatherum calamagrostis (grass)], on concentrated flow erosion rates. Ten functional traits, describing plant morphological and biomechanical features, were measured on each tested sample. Analyses were performed to identify traits that determine plant root effects on erosion control. Erosion rates were lowest for samples of Robinia pseudo acacia, intermediate in Achnatherum calamagrostis and highest in Pinus nigra austriaca. The three species also differed strongly in their traits. Principal components analysis showed that the erosion‐reducing potential of plant species was negatively correlated to root diameter and positively correlated to the percentage of fine roots. The results highlighted the role of small flexible roots in root reinforcement processes, and suggested the importance of high root surface and higher tensile strength for soil stabilization. By combining flume experiment to plant functional traits measurements, we identified root system features influencing plant species performance for soil protection against concentrated flow erosion. Plant functional traits related to species efficiency for erosion control represent useful tools to improve the diagnosis of land vulnerability to erosion, plant community resistance and the prediction of ecosystem functioning after ecological restoration. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Marrel Amandine Perot Nadia Mottet Clémentine 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(3):959-974
Stochastic Environmental Research and Risk Assessment - To evaluate the consequences on human health of radionuclide releases in the environment, numerical simulators are used to model the... 相似文献
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In order to clarify the erosion processes on a marly bare slope in the Southern Alps, the erosion processes in a steep and erodible slope composed of the Black Marls Formation were observed by a time‐lapse video camera. The observations revealed that miniature debris flows (MDFs) occurred at the time of the rainfall‐runoff event in which the most severe erosion took place in the whole observation period of 3 months. Analysis of the camera images showed some characteristics of the MDFs, and these are discussed in the context of real rainfall‐runoff phenomena observed at the outlet of a small experimental basin including the visually observed slope. The following results were obtained. (1) A rough estimation of the total amount of sediment discharge by the MDFs showed that it was not negligible quantitatively. (2) The MDFs occurred only during the rising limb of the hydrograph during 6 minutes. (3) Based on this observation and a review of the literature, in a very steep and highly erodible slope, MDFs or similar phenomena might play an important role in the erosion and transport processes. Copyright © 2008 John Wiley and Sons, Ltd. 相似文献
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Spatial variability in organic material sinking export in the Hudson Bay system,Canada, during fall 总被引：1，自引：0，他引：1
Amandine Lapoussière Christine Michel Michel Gosselin Michel Poulin 《Continental Shelf Research》2009
Spatial variations in the sinking export of organic material were assessed within the Hudson Bay system (i.e., Hudson Bay, Hudson Strait and Foxe Basin) during the second oceanographic expedition of ArcticNet, on board the CCGS Amundsen in early fall 2005. Sinking fluxes of particulate organic material were measured using short-term free-drifting particle interceptor traps deployed at 50, 100 and 150 m for 8–20 h at eight stations. Measurements of chlorophyll a (chl a), pheopigments (pheo), particulate organic carbon (POC), biogenic silica (BioSi), protists, fecal pellets and bacteria were performed on the collected material. In parallel, sea surface salinity and temperature were determined at 121 stations in the Hudson Bay system. Three hydrographic regions presenting different sedimentation patterns were identified based on average surface salinity and temperature. Hudson Strait was characterized by a marine signature, with high salinity (average=32.3) and low temperature (average=2.1 °C). Eastern Hudson Bay was strongly influenced by river runoff and showed the lowest average salinity (26.6) and highest average temperature (7.6 °C) of the three regions. Western Hudson Bay showed intermediate salinity (average=29.4) and temperature (average=4.4 °C). Sinking fluxes of total pigments (chl a+pheo: 3.37 mg m−2 d−1), diatom-associated carbon (19.8 mg m−2 d−1) and BioSi (50.2 mg m−2 d−1) at 50 m were highest in Hudson Strait. Eastern Hudson Bay showed higher sinking fluxes of total pigments (0.52 mg m−2 d−1), diatom-associated carbon (3.29 mg m−2 d−1) and BioSi (36.6 mg m−2 d−1) compared to western Hudson Bay (0.19, 0.05 and 7.76 mg m−2 d−1, respectively). POC sinking fluxes at 50 m were low and relatively uniform throughout the Hudson Bay system (50.0–76.8 mg C m−2 d−1), but spatial variations in the composition of the sinking organic material were observed. A large part (37–78%) of the total sinking POC was unidentifiable by microscopic observation and was qualified as amorphous detritus. Considering only the identifiable material, the major contributors to the POC sinking flux were intact protist cells in Hudson Strait (28%), fecal pellets in eastern Hudson Bay (52%) and bacteria in western Hudson Bay (17%). A significant depth-related attenuation of the POC sinking fluxes (average loss between 50 and 150 m=32%) and a significant increase in the BioSi:POC ratio (average increase between 50 and 150 m=76%) were observed in Hudson Strait and eastern Hudson Bay. For all other sinking fluxes and composition ratios, we found no statistically significant difference with depth. These results show that during fall, the sinking export of total POC from the euphotic zone remained fairly constant throughout the Hudson Bay system, whereas other components of the organic sinking material (e.g., chl a, BioSi, fecal pellets, protist cells) showed strong spatial variations. 相似文献
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Amplification of the storm surges in shallow waters of the Pertuis Charentais (Bay of Biscay,France) 总被引：1，自引：1，他引：0
The Pertuis Charentais are shallow coastal embayments formed by the islands of Oleron and Re in the north-eastern Bay of Biscay.
The low-lying coasts of the Pertuis Charentais are susceptible to extensive flooding caused by the storm surges generated
in the North Atlantic. Numerical modelling of the 24 October 1999 surge event is performed in the present study in order to
elucidate the impact of the wind-wave-tide-surge interactions on the surge propagation in the Pertuis Charentais. A 2D numerical
model is constructed to simulate the wave and tide-surge propagation on a high-resolution finite-element grid by using the
TELEMAC and TOMAWAC software. The effect of the wave-induced enhancement on the sea surface drag and on the bottom friction
is evaluated by using the models of Janssen (1991) and Christoffersen and Jonsson (1985), respectively. The radiation stress is estimated by employing the approach of Longuet-Higgins and Stewart (1964). It is demonstrated that the peak surge in the night on 23–24 October has been amplified inside the Pertuis Charentais by
about 20 cm due to the wind-wave interactions with the tide-surge currents. These interactions are strongest at the entrance
to the Pertuis Charentais where the sea surface drag coefficient is significantly increased by the wind-wave coupling. The
effect of the wave-tide-surge interactions is large enough to be included in the flood forecasting systems of this region. 相似文献
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35 Seasons of U.S. Antarctic Meteorites: A Pictorial Guide to the Collection,edited by K. Righter,C. M. Corrigan,T. J. McCoy and R. P. Harvey. Hoboken,New Jersey: Wiley, 2014, 320 p. $99.95, hardcover (ISBN #978‐1‐118‐79832‐4).
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下载免费PDF全文 Nicolle E. B. Zellner 《Meteoritics & planetary science》2015,50(12):2140-2141
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Influence of high-resolution wind forcing on hydrodynamic modeling of the Gulf of Lions 总被引：2，自引：2，他引：0
Amandine Schaeffer Pierre Garreau Anne Molcard Philippe Fraunié Yann Seity 《Ocean Dynamics》2011,61(11):1823-1844
The impact of the choice of high-resolution atmospheric forcing on ocean summertime circulation in the Gulf of Lions (GoL;
Mediterranean Sea) is evaluated using three different datasets: AROME (2.5 km, 1 h), ALADIN (9.5 km, 3 h), and MM5 (9 km,
3 h). A short-term ocean simulation covering a 3-month summer period was performed on a 400-m configuration of the GoL. The
main regional features of both wind and oceanic dynamics were well-reproduced by all three atmospheric models. Yet, at smaller
scales and for specific hydrodynamic processes, some differences became apparent. Inertial oscillations and mesoscale variability
were accentuated when high-resolution forcing was used. Sensitivity tests suggest a predominant role for spatial rather than
temporal resolution of wind. The determinant influence of wind stress curl was evidenced, both in the representation of a
mesoscale eddy structure and in the generation of a specific upwelling cell in the north-western part of the gulf. 相似文献
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Steve Pye Christophe McGlade Chris Bataille Gabrial Anandarajah Amandine Denis-Ryan Vladimir Potashnikov 《Climate Policy》2016,16(4):S92-S109
The role of fossils fuels in national economies will change radically over the next 40 years under a strong climate regime. However, capturing this changing role through national-based analyses is challenging due to the global nature of fossil fuel demand and resulting trade patterns. This article sets out the limitations of existing national-scale decarbonization analyses in adequately capturing global conditions and explores how the introduction of a global modelling framework could provide vital insights, particularly for those countries that are dependent on fossil fuel exports or imports.The article shows that fossil fuel use will significantly decline by 2050, although gas will have an important transition role. This leaves large fossil fuel exporters exposed, the extent of which is determined by mitigation action in different regions and especially by the pathways adopted by the larger Asian economies. We find that global-scale models provide critical insights that complement the more detailed national analyses and should play a stronger role in informing deep decarbonization pathways (DDPs). They also provide an important basis for exploring key uncertainties around technology uptake, mitigation rates and how this plays out in the demand for fossil fuels. However, use of global models also calls for improved representation of country specifics in global models, which can oversimplify national economic and political realities. Using both model scales provides important insights that are complementary but that can challenge the other’s orthodoxy. However, neither can replace the other’s strengths.Policy relevance:In recent years, how global fossil fuel markets will evolve under different climate regimes has been subject to much debate and analysis. This debate includes whether investments in fossil fuel production still make sense or will be exposed in the future to liabilities associated with high carbon prices. This is important for governments who need to develop coherent policy in relation to fossil fuel sectors and their role as drivers of economic growth and in providing for domestic energy needs. This article argues that national analyses need to be fully cognizant of the global-scale transition, which can be informed by using a multi-scale modelling approach. 相似文献