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Four policies might close the gap between the global GHG emissions expected for 2020 on the basis of current (2013) policies and the reduced emissions that will be needed if the long-term global temperature increase can be kept below the 2 °C internationally agreed limit. The four policies are (1) specific energy efficiency measures, (2) closure of the least-efficient coal-fired power plants, (3) minimizing methane emissions from upstream oil and gas production, and (4) accelerating the (partial) phase-out of subsidies to fossil-fuel consumption. In this article we test the hypothesis of the International Energy Agency (IEA) that these policies will not result in a loss of gross domestic product (GDP) and we estimate their employment effects using the E3MG global macro-econometric model. Using a set of scenarios we assess each policy individually and then consider the outcomes if all four policies were implemented simultaneously. We find that the policies are insufficient to close the emissions gap, with an overall emission reduction that is 30% less than that found by the IEA. World GDP is 0.5% higher in 2020, with about 6 million net jobs created by 2020 and unemployment reduced.

Policy relevance

The gap between GHG emissions expected under the Copenhagen and Cancun Agreements and that needed for emissions trajectories to have a reasonable chance of reaching the 2 °C target requires additional policies if it is to be closed. This article uses a global simulation model E3MG to analyse a set of policies proposed by the IEA to close the gap and assesses their macroeconomic effects as well as their feasibility in closing the gap. It complements the IEA assessment by estimating the GDP and employment implications separately by the different policies year by year to 2020, by major industries, and by 21 world regions.  相似文献   

3.
We performed seismic waveform inversions and numerical landslide simulations of deep-seated landslides in Japan to understand the dynamic evolution of friction of the landslides. By comparing the forces obtained from a numerical simulation to those resolved from seismic waveform inversion, the coefficient of friction during sliding was well-constrained between 0.3 and 0.4 for landslides with volumes of 2–8 ×106 m3. We obtained similar coefficients of friction for landslides with similar scale and geology, and they are consistent with the empirical relationship between the volume and dynamic coefficient of friction obtained from the past studies. This hybrid method of the numerical simulation and seismic waveform inversion shows the possibility of reproducing or predicting the movement of a large-scale landslide. Our numerical simulation allows us to estimate the velocity distribution for each time step. The maximum velocity at the center of mass is 12–36 m/s and is proportional to the square root of the elevation change at the center of mass of the landslide body, which suggests that they can be estimated from the initial DEMs. About 20% of the total potential energy is transferred to the kinetic energy in our volume range. The combination of the seismic waveform inversion and the numerical simulation helps to obtain the well-constrained dynamic coefficients of friction and velocity distribution during sliding, which will be used in numerical models to estimate the hazard of potential landslides.  相似文献   
4.
The matching of asteroids and meteorites is a significant step toward a better understanding of the origin, structure, and history of the solar system. We propose a data‐driven approach for investigating common taxonomic structure between asteroids and meteorites; C‐, S‐, and V‐type for the former, and carbonaceous chondrite, ordinary chondrite, and howardite‐eucrite‐diogenite (HED) meteorite for the latter. In the numerical experiments, by checking whether the taxonomy information of meteorites improves classification for asteroid data, we examine the existence of common structure over the two domains. For this purpose, we compare the resultant accuracies of two clustering methods which are with/without the guidance of meteorite data. We observe that the guidance of meteorite taxonomy improves the accuracy for classifying asteroids, either with the reflectance spectra or major chemical compositions of meteorites. This fact serves as a piece of evidence that there is a common taxonomic structure and links between meteorites and asteroids, supporting a long‐standing hypothesis.  相似文献   
5.
Basin models can simulate geological, geochemical and geophysical processes and potentially also the deep biosphere, starting from a burial curve, assuming a thermal history and utilizing other experimentally obtained data. Here, we apply basin modelling techniques to model cell abundances within the deep coalbed biosphere off Shimokita Peninsula, Japan, drilled during Integrated Ocean Drilling Program Expedition 337. Two approaches were used to simulate the deep coalbed biosphere: (a) In the first approach, the deep biosphere was modelled using a material balance approach that treats the deep biosphere as a carbon reservoir, in which fluxes are governed by temperature-controlled metabolic processes that retain carbon via cell-growth and cell-repair and pass it back via cell-damaging reactions. (b) In the second approach, the deep biosphere was modelled as a microbial community with a temperature-controlled growth ratio and carrying capacity (a limit on the size of the deep biosphere) modulated by diagenetic-processes. In all cases, the biosphere in the coalbeds and adjacent habitat are best modelled as a carbon-limited community undergoing starvation because labile sedimentary organic matter is no longer present and petroleum generation is yet to occur. This state of starvation was represented by the conversion of organic carbon to authigenic carbonate and the formation of kerogen. The potential for the biosphere to be stimulated by the generation of carbon-dioxide from the coal during its transition from brown to sub-bituminous coal was evaluated and a net thickness of 20 m of lignite was found sufficient to support an order of magnitude greater number of cells within a low-total organic carbon (TOC) horizon. By comparison, the stimulation of microbial populations in a coalbed or high-TOC horizon would be harder to detect because the increase in population size would be proportionally very small.  相似文献   
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Abstract— Chondrules in the Bali-like CV chondrite Kaba and the Allende-like portion of the Mokoia breccia have been studied to explore the relationship between hydrous alteration to form phyllosilicates and anhydrous alteration resulting in secondary olivine zonation, replacement of enstatite by ferroan olivine and formation of feldspathoids (nepheline and sodalite). All Kaba chondrules experienced extensive hydrous alteration; whereas, anhydrous alteration was minor and resulted only in the olivine zonation. On the other hand, all of the Mokoia chondrules experienced both extensive anhydrous and hydrous alteration. Bronzite rims formed between relic enstatite grains and phyllosilicates in both Kaba and Mokoia during the hydrous alteration. Petrographic observations indicate that phyllosilicates in Mokoia postdate formation of the secondary ferroan olivine and feldspathoids. We conclude that anhydrous alteration in Kaba and Mokoia predated hydrous alteration and took place before accretion of chondrules into the CV parent asteroid.  相似文献   
8.
WONN  SOH  KAZUO  NAKAYAMA & TAKU  KIMURA 《Island Arc》1998,7(3):330-341
The Pleistocene Ashigara Basin and adjacent Tanzawa Mountains, Izu collision zone, central Japan, are examined to better understand the development of an arc–arc orogeny, where the Izu–Bonin – Mariana (IBM) arc collides with the Honshu Arc. Three tectonic phases were identified based on the geohistory of the Ashigara Basin and the denudation history of the Tanzawa Mountains. In phase I, the IBM arc collided with the Honshu Arc along the Kannawa Fault. The Ashigara Basin formed as a trench basin, filled mainly by thin-bedded turbidites derived from the Tanzawa Mountains together with pyroclastics. The Ashigara Basin subsided at a rate of 1.7 mm/year, and the denudation rate of the Tanzawa Mountains was 1.1 mm/year. The onset of Ashigara Basin Formation is likely to be older than 2.2 Ma, interpreted as the onset of collision along the Kannawa Fault. Significant tectonic disruption due to the arc–arc collision took place in phase II, ranging from 1.1 to 0.7 Ma in age. The Ashigara Basin subsided abruptly (4.6 mm/year) and the accumulation rate increased to approximately 10 times that of phase I. Simultaneously, the Tanzawa Mountains were abruptly uplifted. A tremendous volume of coarse-grained detritus was provided from the Tanzawa Mountains and deposited in the Ashigara Basin as a slope-type fan delta. In phase III, 0.7–0.5 Ma, the entire Ashigara Basin was uplifted at a rate of 3.6 mm/year. This uplift was most likely caused by isostatic rebound resulting from stacking of IBM arc crust along the Kannawa Fault which is not active as the decollement fault by this time. The evolution of the Ashigara Basin and adjacent Tanzawa Mountains shows a series of the development of the arc–arc collision; from the subduction of the IBM arc beneath the Honshu Arc to the accretion of IBM arc crust onto Honshu. Arc–arc collision is not the collision between the hard crusts (massif) like a continent–continent collision, but crustal stacking of the subducting IBM arc beneath the Honshu Arc intercalated with very thick trench fill deposits.  相似文献   
9.
We analyse Japanese newspaper coverage of global warming from January 1998 to July 2007 and how public opinion during parts of that period were influenced by newspaper coverage. We show that a dramatic increase in newspaper coverage of global warming from January 2007 correlated with an increase in public concern for the issue. Before January 2007, we find that coverage of global warming had an immediate but short-term influence on public concern. With such transitory high levels of media coverage we suggest that for more effective communication of climate change, strategies aimed at maintaining mass-media coverage of global warming are required.  相似文献   
10.
The large organic matter flow in tropical coastal areas is recognized as an important process in the global carbon(C)cycle.However,the nature of organic matter flow in semi-enclosed tropical estuaries remains unclear due to the various environmental processes(tidal change,river flow,waves from the sea,and internal circulation)and organic matter sources therein.Thus,sediment organic matter(SOM)sources,and their distribution pattern,are key to understanding ecosystem material flow.Our research in the Batan Bay Estuary,Philippines,a semi-enclosed estuary under large mangrove deforestation,was conducted to determine ecosystem properties through analysis of C and nitrogen stable isotope ratios and environmental factors.First,we determined that mangrove litter,microphytobenthos,and phytoplankton are the main SOM sources in the Batan Bay Estuary.Second,the estuary was classified into three ecological zones(the Bay zone,Back-barrier zone,and River zone).In addition,we estimated SOM source ratios using the Stable Isotope Analysis in R package and determined different organic matter sources in different zone.The high ratios of mangrove litter as SOM indicate that a large amount of terrestrial plant organic matter remains despite the heavy mangrove deforestation that has occurred since the 1980s,and that the Back-barrier zone consists of a different type of ecosystem that promotes accumulation of C from mangrove litter and microphytobenthos.  相似文献   
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