ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Mineral Physics, Rheology, Heat Flow and Volcanology  (29)
  • Natural Disasters  (29)
  • Oxford University Press  (58)
  • American Institute of Physics (AIP)
  • International Union of Crystallography (IUCr)
  • 2015-2019  (58)
Collection
Keywords
Publisher
Years
Year
  • 1
    facet.materialart.
    Unknown
    The Value of Heterogeneous Property Rights and the Costs of Water Volatility (2017)
    Oxford University Press
    Details
    Publication Date: 2017-01-05
    Description: The system of prior appropriation in the Western Unites States prioritizes property rights for water based on the establishment of beneficial use, creating a hierarchy where rights initiated first are more secure. I estimate the demand for security in water rights through their capitalization in agricultural property markets in the Yakima River Basin, a major watershed in Washington State. All water rights are satisfied in an average year, so the relative value of secure property rights is a function of water supply volatility and the costs of droughts are predominantly born by those with weak rights. In aggregate, security in water rights does not capitalize into property values at the irrigation district level; however, there is heterogeneity in the premium for secure water rights. The lack of a premium for district-level water security is robust to a variety of econometric methods to account for correlated district unobservables, and the null result produces an economically significant upper bound on the value to water security for the district. The ability for farmers to adapt to water supply volatility, as well as expectations about water markets and government infrastructure investment, are leading explanations for the lack of an aggregate premium. These explanations are supported by the pattern of heterogeneity in the water security premium.
    Keywords: Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q21 - Demand and Supply, Q24 - Land, Q25 - Water, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Temperature Changes, Household Consumption, and Internal Migration: Evidence from Tanzania (2016)
    Oxford University Press
    Details
    Publication Date: 2016-07-09
    Description: Large rural-urban wage gaps observed in many developing countries are suggestive of barriers to migration that keep potential migrants in rural areas. Using long panel data spanning nearly two decades, I study the extent to which migration rates are constrained by liquidity constraints in rural Tanzania. The analysis begins by quantifying the impact of weather variation on household welfare. The results show how household consumption co-moves with temperature, rendering households vulnerable to local weather events. These temperature-induced income shocks are then found to inhibit long-term migration among men, thus preventing them from tapping into the opportunities brought about by geographical mobility.
    Keywords: O12 - Microeconomic Analyses of Economic Development, O15 - Human Resources ; Human Development ; Income Distribution ; Migration, Q54 - Climate ; Natural Disasters ; Global Warming, R23 - Regional Migration ; Regional Labor Markets ; Population
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Quantitative reconstruction of thermal and dynamic characteristics of lava flow from surface thermal measurements (2016)
    Oxford University Press
    Details
    Publication Date: 2016-05-05
    Description: We study a model of lava flow to determine its thermal and dynamic characteristics from thermal measurements of the lava at its surface. Mathematically this problem is reduced to solving an inverse boundary problem. Namely, using known conditions at one part of the model boundary we determine the missing condition at the remaining part of the boundary. We develop a numerical approach to the mathematical problem in the case of steady-state flow. Assuming that the temperature and the heat flow are prescribed at the upper surface of the model domain, we determine the flow characteristics in the entire model domain using a variational (adjoint) method. We have performed computations of model examples and showed that in the case of smooth input data the lava temperature and the flow velocity can be reconstructed with a high accuracy. As expected, a noise imposed on the smooth input data results in a less accurate solution, but still acceptable below some noise level. Also we analyse the influence of optimization methods on the solution convergence rate. The proposed method for reconstruction of physical parameters of lava flows can also be applied to other problems in geophysical fluid flows.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Seismic-acoustic energy partitioning during a paroxysmal eruptive phase of Tungurahua volcano, Ecuador (2016)
    Oxford University Press
    Details
    Publication Date: 2016-05-06
    Description: Studies of discrete volcanic explosions, that usually last less than 2 or 3 min, have suggested that the partitioning of seismic-acoustic energy is likely related to a range of physical mechanisms that depend on magma properties and other physical constraints such as the location of the fragmentation surface. In this paper, we explore the energy partition of a paroxysmal eruptive phase of Tungurahua volcano that lasted for over 4 hr, on 2006 July 14–15, using seismic-acoustic information recorded by stations on its flanks (near field). We find evidence of a linear scaling between seismic and acoustic energies, with time-dependent intensities, during the sustained explosive phase of the eruption. Furthermore, we argue that this scaling can be explained by two different processes: (1) the fragmentation region ultimately acts as the common source of energy producing both direct seismic waves, that travel through the volcanic edifice, and direct acoustic waves coming from a disturbed atmosphere above the summit; (2) the coupling of acoustic waves with the ground to cause seismic waves. Both processes are concurrent, however we have found that the first one is dominant for seismic records below 4 Hz. Here we use the linear scaling of intensities to construct seismic and acoustic indices, which, we argue, could be used to track an ongoing eruption. Thus, especially in strong paroxysms that can produce pyroclastic flows, the index correlation and their levels can be used as quantitative monitoring parameters to assess the volcanic hazard in real time. Additionally, we suggest from the linear scaling that the source type for both cases, seismic and acoustic, is dipolar and dominant in the near field.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Drought Index Insurance for the Central Valley Project in California (2016)
    Oxford University Press
    Details
    Publication Date: 2016-08-20
    Description: A multi-year drought has taken a severe toll on the agricultural economy of California’s Central Valley. Index insurance is an instrument with the potential to protect water users from economic losses due to periodic water shortages. An index insurance product based on the Sacramento Index and adapted to the Central Valley Project water supply is proposed. To address the potential for intertemporal adverse selection, three product designs are suggested: (1) "early bird" insurance; (2) variable premium insurance; and (3) variable deductible insurance. The performance of the designs are assessed using loss functions from the Westlands Water District in the San Joaquin Valley.
    Keywords: Q14 - Agricultural Finance, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    The thermal regime around buried submarine high-voltage cables (2016)
    Oxford University Press
    Details
    Publication Date: 2016-06-19
    Description: The expansion of offshore renewable energy infrastructure and the need for trans-continental shelf power transmission require the use of submarine high-voltage (HV) cables. These cables have maximum operating surface temperatures of up to 70 °C and are typically buried 1–2 m beneath the seabed, within the wide range of substrates found on the continental shelf. However, the heat flow pattern and potential effects on the sedimentary environments around such anomalously high heat sources in the near-surface sediments are poorly understood. We present temperature measurements from a 2-D laboratory experiment representing a buried submarine HV cable, and identify the thermal regimes generated within typical unconsolidated shelf sediments—coarse silt, fine sand and very coarse sand. We used a large (2 x 2.5 m 2 ) tank filled with water-saturated spherical glass beads (ballotini) and instrumented with a buried heat source and 120 thermocouples to measure the time-dependent 2-D temperature distributions. The observed and corresponding Finite Element Method simulations of the steady state heat flow regimes and normalized radial temperature distributions were assessed. Our results show that the heat transfer and thus temperature fields generated from submarine HV cables buried within a range of sediments are highly variable. Coarse silts are shown to be purely conductive, producing temperature increases of 〉10 °C up to 40 cm from the source of 60 °C above ambient; fine sands demonstrate a transition from conductive to convective heat transfer between cf. 20 and 36 °C above ambient, with 〉10 °C heat increases occurring over a metre from the source of 55 °C above ambient; and very coarse sands exhibit dominantly convective heat transfer even at very low ( cf. 7 °C) operating temperatures and reaching temperatures of up to 18 °C above ambient at a metre from the source at surface temperatures of only 18 °C. These findings are important for the surrounding near-surface environments experiencing such high temperatures and may have significant implications for chemical and physical processes operating at the grain and subgrain scale; biological activity at both microfaunal and macrofaunal levels; and indeed the operational performance of the cables themselves, as convective heat transport would increase cable current ratings, something neglected in existing standards.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Quality Matters More Than Quantity: Asymmetric Temperature Effects on Crop Yield and Quality Grade (2016)
    Oxford University Press
    Details
    Publication Date: 2016-07-09
    Description: Climate change affects agriculture by altering not only output quantity, but also crop quality. We quantify the economic impacts of climate change on agriculture through changes in both quantity and quality, where quality is measured by crop grades. Our model controls for methodological issues regarding sample selection, aggregation, phenology, and nonlinearity. The empirical application to Japanese rice production indicates that temperature effects are asymmetric: quantity is especially vulnerable to cold, whereas quality is vulnerable to extremely high temperature. Using these results, we simulate the effect of global warming, and we find that warming (a 3 °C increase) increases farm revenues by improving yield but decreases revenues as a result of deteriorating quality. The net effect is negative, suggesting that quality matters more than quantity. The negative effect, however, can be mitigated by shifting cultivation periods and/or regions. Overall, our results suggest that the estimated impacts of climate change and adaptation strategies could be severely misleading unless quality is considered.
    Keywords: L15 - Information and Product Quality ; Standardization and Compatibility, Q10 - General, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Alternative Metrics for Comparing Domestic Climate Change Mitigation Efforts and the Emerging International Climate Policy Architecture (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: The availability of practical mechanisms for comparing domestic efforts aimed at mitigating global climate change is important for the stability, equity, and efficiency of international climate agreements. We examine a variety of metrics that could be used to compare countries’ climate change mitigation efforts and illustrate their potential application to large developed and developing countries. Because there is no single, comprehensive, measurable metric that could be applied to all countries, we suggest using a set of indicators to characterize and compare mitigation effort, akin to using a set of economic statistics to indicate the health of the macroeconomy. Given the iterative pledge-and-review approach that is emerging in the current climate change negotiations, participation, commitment, and compliance could be enhanced if this set of indicators is able to show that all parties are doing their "fair share," both prospectively and retrospectively. The latter, in particular, highlights the need for a well-functioning policy surveillance regime. ( JEL : Q54, Q58, F55)
    Keywords: Q54 - Climate ; Natural Disasters ; Global Warming, Q58 - Government Policy, F55 - International Institutional Arrangements
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    The Economics of Wine, Weather, and Climate Change (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: In this article, we provide an overview of the extensive literature on the impact of weather and climate on grapes and wine, with the goal of identifying how climate change is likely to affect their production. We first discuss the physical impact of weather on vine phenology (i.e., the timing of biological events such as bud break or flowering), berry composition, and yields. Then we examine the economic literature that measures the effects of temperature on wine quality, prices, costs, and profits and, based on this review, infer how climate change will affect these variables. We also describe what has been learned thus far about possible adaptation strategies for grape growers that would allow them to mitigate the economic effects of climate change. We conclude that climate change is likely to produce both winners and losers, with the winners being those located closer to the North and South Poles. There are also likely to be some substantial short-run costs as growers adapt to climate change. Nevertheless, wine making has survived through thousands of years of recorded history, a history that has included significant climate changes. ( JEL : Q13, Q18, Q54)
    Keywords: Q13 - Agricultural Markets and Marketing ; Cooperatives ; Agribusiness, Q18 - Agricultural Policy ; Food Policy, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    The Impact of the European Union Emissions Trading Scheme on Regulated Firms: What Is the Evidence after Ten Years? (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: This article reviews the recent literature on ex post evaluation of the impacts of the European Union (EU) Emissions Trading Scheme (ETS) on regulated firms in the industrial and power sectors. We summarize the findings from original research papers concerning three broadly defined impacts: carbon dioxide emissions, economic performance and competitiveness, and innovation. We conclude by highlighting gaps in the current literature and suggesting priorities for future research on this landmark policy. ( JEL : Q52, Q54, Q58)
    Keywords: Q52 - Pollution Control Costs ; Distributional Effects ; Employment Effects, Q54 - Climate ; Natural Disasters ; Global Warming, Q58 - Government Policy
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 11
    facet.materialart.
    Unknown
    The European Union Emissions Trading System: Ten Years and Counting (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: This article provides an introduction to the European Union (EU) Emissions Trading System (ETS). First we describe the legislative development of the EU ETS, its evolution from free allocation to auctioning and centralized allocation rules, its relationship to the Kyoto Protocol and other trading systems, and its relationship to other EU climate and energy policies. This is followed by an assessment of the performance of the EU ETS, which focuses in particular on emissions, allowance prices, and the use of offsets. We conclude with a discussion of the current debate about the future of the EU ETS and proposals for changes to both the EU ETS and the climate policy environment in which it operates. ( JEL : Q54, Q58)
    Keywords: Q54 - Climate ; Natural Disasters ; Global Warming, Q58 - Government Policy
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 12
    facet.materialart.
    Unknown
    The Climate Change Adaptation Literature (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: The December 2015 Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change meetings in Paris are likely to yield a global agreement that will slow the world’s growth of greenhouse gas emissions, but this agreement is unlikely to guarantee a decline in global emissions in the near future. Given this reality, climate change adaptation is an increasingly important topic for discussion and study. Although much research has focused on the macroeconomic relationship between economic growth and temperature at the national and/or annual level, microeconomic analysis also offers valuable insights. This Reflections discusses recent work on household and firm responses to three climate change challenges: increased summer heat, higher food prices, and increased natural disaster risk. ( JEL : Q54)
    Keywords: Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 13
    facet.materialart.
    Unknown
    The influence of normal stress and sliding velocity on the frictional behaviour of calcite at room temperature: insights from laboratory experiments and microstructural observations (2016)
    Oxford University Press
    Details
    Publication Date: 2016-03-03
    Description: The presence of calcite in and near faults, as the dominant material, cement, or vein fill, indicates that the mechanical behaviour of carbonate-dominated material likely plays an important role in shallow- and mid-crustal faulting. To better understand the behaviour of calcite, under loading conditions relevant to earthquake nucleation, we sheared powdered gouge of Carrara Marble, 〉98 per cent CaCO 3 , at constant normal stresses between 1 and 100 MPa under water-saturated conditions at room temperature. We performed slide-hold-slide tests, 1–3000 s, to measure the amount of static frictional strengthening and creep relaxation, and velocity-stepping tests, 0.1–1000 μm s –1 , to evaluate frictional stability. We observe that the rates of frictional strengthening and creep relaxation decrease with increasing normal stress and diverge as shear velocity is increased from 1 to 3000 μm s –1 during slide-hold-slide experiments. We also observe complex frictional stability behaviour that depends on both normal stress and shearing velocity. At normal stresses less than 20 MPa, we observe predominantly velocity-neutral friction behaviour. Above 20 MPa, we observe strong velocity-strengthening frictional behaviour at low velocities, which then evolves towards velocity-weakening friction behaviour at high velocities. Microstructural analyses of recovered samples highlight a variety of deformation mechanisms including grain size reduction and localization, folding of calcite grains and fluid-assisted diffusion mass transfer processes promoting the development of calcite nanograins in the highly deformed portions of the experimental fault. Our combined analyses indicate that calcite fault gouge transitions from brittle to semi-brittle behaviour at high normal stress and slow sliding velocities. This transition has important implications for earthquake nucleation and propagation on faults in carbonate-dominated lithologies.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 14
    facet.materialart.
    Unknown
    Endogenous farm-type selection, endogenous irrigation, and spatial effects in Ricardian models of climate change (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-20
    Description: In the estimation of Ricardian models the endogeneity of adaptation measures is typically ignored. In this article we propose a new estimation strategy that explicitly recognises the endogeneity of the farm type and irrigation to climate. Based on the latest census data on over 270,000 farms in Germany, we estimate a cross-sectional, spatial-IV model that decomposes the effects of climate on farm profitability into direct (unmediated) and indirect (mediated by the variables that reflect adaptation). Our results show that neglecting the endogenous nature of adaptation measures may substantially bias the magnitude of the total effect of climate on farm profitability.
    Keywords: C21 - Cross-Sectional Models ; Spatial Models ; Treatment Effect Models, C25 - Discrete Regression and Qualitative Choice Models, C36- Instrumental Variables (IV) Estimation, Q18 - Agricultural Policy ; Food Policy, Q51 - Valuation of Environmental Effects, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0165-1587
    Electronic ISSN: 1464-3618
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 15
    facet.materialart.
    Unknown
    Dynamic elastic moduli during isotropic densification of initially granular media (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-03
    Description: The elastic properties of homogeneous, isotropic materials are well constrained. However, in heterogeneous and evolving materials, these essential properties are less well-explored. During sintering of volcanic ash particles by viscous processes as well as during compaction and cementation of sediments, microstructure and porosity undergo changes that affect bulk dynamic elastic properties. Here using a model system of glass particles as an analogue for initially granular rock-forming materials, we have determined porosity and P -wave velocity during densification. Using these results, we test models for the kinetics of densification and the resultant evolution of the elastic properties to derive a quantitative description of the coupling between the kinetics of isotropic densification and the evolving dynamic elastic moduli. We demonstrate the power of the resultant model on a wide range of data for non-coherent sediments as well as sedimentary and volcanic rocks. We propose that such constraints be viewed as an essential ingredient of time-dependent models for the deformation of evolving materials in volcanoes and sedimentary basins.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 16
    facet.materialart.
    Unknown
    Velocity variations associated with the large 2010 eruption of Merapi volcano, Java, retrieved from seismic multiplets and ambient noise cross-correlation (2016)
    Oxford University Press
    Details
    Publication Date: 2016-05-14
    Description: We present a study of the seismic velocity variations that occurred in the structure before the large 2010 eruption of Merapi volcano. For the first time to our knowledge, the technique of coda wave interferometry is applied to both families of similar events (multiplets) and to correlation functions of seismic noise. About half of the seismic events recorded at the summit stations belong to one of the ten multiplets identified, including 120 similar events that occurred in the last 20 hr preceding the eruption onset. Daily noise cross-correlation functions (NCF) were calculated for the six pairs of short-period stations available. Using the stretching method, we estimate time-series of apparent velocity variation (AVV) for each multiplet and each pair of stations. No significant velocity change is detected until September 2010. From 10 October to the beginning of the eruption on 26 October, a complex pattern of AVV is observed with amplitude of up to ±1.5 per cent. Velocity decrease is first observed from families of deep events and then from shallow earthquakes. In the same period, AVV with different signs and chronologies are estimated from NCF calculated for various station pairs. The location in the horizontal plane of the velocity perturbations related with the AVV obtained from NCF is estimated by using an approach based on the radiative transfer approximation. Although their spatial resolution is limited, the resulting maps display velocity decrease in the upper part of the edifice in the period 12–25 October. After the eruption onset, the pattern of velocity perturbations is significantly modified with respect to the previous one. We interpret these velocity variations in the framework of a scenario of magmatic intrusion that integrates most observations. The perturbation of the stress field associated with the magma migration can induce both decrease and increase of the seismic velocity of rocks. Thus the detected AVVs can be considered as precursors of volcanic eruptions in andesitic volcanoes, without taking their sign into account.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 17
    facet.materialart.
    Unknown
    Linear stability analysis for hydrothermal alteration of kimberlitic rocks (2016)
    Oxford University Press
    Details
    Publication Date: 2016-05-06
    Description: The influx of groundwater into hot kimberlite deposits results in the reaction of water with olivine-rich rocks. The products of the reaction are serpentine and release of latent heat. The rise of temperature due to the heat release increases the rate of the reaction. Under certain conditions, this self-speeding up of the reaction can result in instabilities associated with a significantly higher final serpentinization in slightly warmer regions of the kimberlite deposit. We conduct linear stability analysis of serpentinization in an isolated volume of porous kimberlitic rocks saturated with water and an inert gas. There is a counteracting interplay between the heat release tending to destabilize the uniform distribution of parameters and the heat conduction tending to stabilize it by smoothing out temperature perturbations. We determine the critical spatial scale separating the parameters where one phenomenon dominates over another. The perturbations of longer-than-critical length grow, whereas the perturbations of shorter-than-critical length fade. The analytical results of the linear stability analysis are supported by direct numerical simulations using a full nonlinear model.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 18
    facet.materialart.
    Unknown
    Brittle and semi-brittle behaviours of a carbonate rock: influence of water and temperature (2016)
    Oxford University Press
    Details
    Publication Date: 2016-05-22
    Description: Inelastic deformation can either occur with dilatancy or compaction, implying differences in porosity changes, failure and petrophysical properties. In this study, the roles of water as a pore fluid, and of temperature, on the deformation and failure of a micritic limestone (white Tavel limestone, porosity 14.7 per cent) were investigated under triaxial stresses. For each sample, a hydrostatic load was applied up to the desired confining pressure (from 0 up to 85 MPa) at either room temperature or at 70 °C. Two pore fluid conditions were investigated at room temperature: dry and water saturated. The samples were deformed up to failure at a constant strain rate of ~10 –5 s –1 . The experiments were coupled with ultrasonic wave velocity surveys to monitor crack densities. The linear trend between the axial crack density and the relative volumetric strain beyond the onset of dilatancy suggests that cracks propagate at constant aspect ratio. The decrease of ultrasonic wave velocities beyond the onset of inelastic compaction in the semi-brittle regime indicates the ongoing interplay of shear-enhanced compaction and crack development. Water has a weakening effect on the onset of dilatancy in the brittle regime, but no measurable influence on the peak strength. Temperature lowers the confining pressure at which the brittle–semi-brittle transition is observed but does not change the stress states at the onset of inelastic compaction and at the post-yield onset of dilatancy.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 19
    facet.materialart.
    Unknown
    Dynamic Adjustment in US Agriculture under Climate Change (2016)
    Oxford University Press
    Details
    Publication Date: 2016-04-24
    Description: We construct a stochastic dynamic dual model to investigate the structural adjustment of two aggregate output and three aggregate input categories in US agriculture under stochastic climatic change. More than a century of national annual data (1910–2011) is used in the empirical analysis. No constraints on asset fixity are imposed. Results indicate that, with rational expectations, both output categories as well as all input categories exhibit quasi-fixity in response to market change and stochastic climate change. Crops adjust more than twice as fast as livestock—49% versus 20% of the way toward their long-run equilibrium in one year. Fertilizer adjusts most rapidly toward equilibrium levels (88% in one year), and capital adjusts most slowly (5% in one year). Labor oscillates rather than converging smoothly toward equilibrium; its distance from equilibrium is the same as if it adjusted 59% of the way toward its optimal level in one year. Failing to anticipate climate change dramatically slows the estimated rate of adjustment for two netputs and modestly speeds the rate for two others, thus likely increasing overall adjustment costs. Failing to account for uncertainty in anticipated climate change has little impact on adjustment rates.
    Keywords: Q11 - Aggregate Supply and Demand Analysis ; Prices, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 20
    facet.materialart.
    Unknown
    Agriculture Afforestation for Carbon Sequestration Under Carbon Markets in the United States: Leakage Behavior from Regional Allowance Programs (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-10
    Description: This study quantifies how leakage behavior from afforesting agricultural land affects the intensification of agricultural production. In particular, we examine the leakage percentage from carbon offset allowance at specific southern regions in the United States as a part of a carbon market. We use the Forest and Agriculture Sector Optimization Model-Greenhouse Gases model to examine responses between sectors as part of the regional afforestation policy analysis. Regional characteristics and a policy's time frame are found to play important roles in achieving net gains, in terms of greenhouse gases stored, from such regional policies. In some cases, however, leakage greater than 100% is evident.
    Keywords: Q23 - Forestry, Q54 - Climate ; Natural Disasters ; Global Warming, R14 - Land Use Patterns
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 21
    facet.materialart.
    Unknown
    Influence of pre-existing topography on downflow lava discharge rates estimated from thermal infrared airborne data (2016)
    Oxford University Press
    Details
    Publication Date: 2016-02-12
    Description: Remote sensing thermal data of active lava flows allow the evaluation of effusion rates. This is made possible by a simple formula relating the lava effusion rate to the heat flux radiated per unit time from the surface of the flow. Due to the assumptions of the model, this formula implies that heat flux, surface temperature and lava temperature vary as a function of the flow thickness. These relationships, never verified or validated before, have been used by several authors as a proof of the weakness of the model. Here, multispectral infrared and visible imaging spectrometer (MIVIS) high spatial resolution (5–10 m) thermal data acquired during Etna's 2001 eruption were used to investigate downflow heat flux variations in the lava flow emitted from a vent located at 2100 m a.s.l. A high correlation between the downflow heat flux and the lava flow thickness (measured from a pre-existing digital elevation model) was found. Topography beneath the flow appears to play an important role both in lava emplacement mechanisms and flow dynamics. MIVIS-derived downflow effusion rates are consistent with the law of conservation of mass assessing the reliability of remote sensing techniques.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 22
    facet.materialart.
    Unknown
    Induced polarization of volcanic rocks - 1. Surface versus quadrature conductivity (2016)
    Oxford University Press
    Details
    Publication Date: 2016-12-22
    Description: We performed complex conductivity measurements on 28 core samples from the hole drilled for the Humu'ula Groundwater Research Project (Hawai'i Island, HI, USA). The complex conductivity measurements were performed at 4 different pore water conductivities (0.07, 0.5, 1.0 or 2.0, and 10 S m –1 prepared with NaCl) over the frequency range 1 mHz to 45 kHz at 22 ± 1 °C. The in-phase conductivity data are plotted against the pore water conductivity to determine, sample by sample, the intrinsic formation factor and the surface conductivity. The intrinsic formation factor is related to porosity by Archie's law with an average value of the cementation exponent m of 2.45, indicating that only a small fraction of the connected pore space controls the transport properties. Both the surface and quadrature conductivities are found to be linearly related to the cation exchange capacity of the material, which was measured with the cobalt hexamine chloride method. Surface and quadrature conductivities are found to be proportional to each other like for sedimentary siliclastic rocks. A Stern layer polarization model is used to explain these experimental results. Despite the fact that the samples contain some magnetite (up to 5 per cent wt.), we were not able to identify the effect of this mineral on the complex conductivity spectra. These results are very encouraging in showing that galvanometric induced polarization measurements can be used in volcanic areas to separate the bulk from the surface conductivity and therefore to define some alteration attributes. Such a goal cannot be achieved with resistivity alone.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 23
    facet.materialart.
    Unknown
    Induced polarization of volcanic rocks. 2. Influence of pore size and permeability (2016)
    Oxford University Press
    Details
    Publication Date: 2016-12-22
    Description: We investigate the relationship between complex conductivity spectra and both permeability and pore mean size and distribution of 22 core samples (21 volcanic rocks and 1 clayey sandstone). The volcanic core samples were extracted from a wellbore drilled for the Humu‘ula Groundwater Research Project in the Humu‘ula saddle region between Mauna Kea and Mauna Loa volcanoes (Hawaii). The quadrature conductivity spectra of volcanic rocks exhibit a subtle, but generally detectable, relaxation frequency in the range 0.3 Hz to 45 kHz similar to the relaxation frequency observed for clayey sandstones. We find a fair relationship between this relaxation frequency and the pore size determined by mercury porosimetry. Combined with the intrinsic formation factor of the core samples, the relaxation frequency can be used as an indicator of the permeability of the material. The predicted values of the permeability are grossly consistent with the permeability values to air (in the range 0.001–100 mD) within two orders of magnitude. The measured permeability values are highly correlated to the peak of the pore size distribution determined from mercury porosimetry divided by the intrinsic formation factor. By fitting the complex conductivity spectra with the pore size distribution, we obtain the normalized chargeability of the core samples, which is, in turn, highly correlated to the measured cation exchange capacity.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 24
    facet.materialart.
    Unknown
    Possible structural control on the 2011 eruption of Puyehue-Cordon Caulle Volcanic Complex (southern Chile) determined by InSAR, GPS and seismicity (2016)
    Oxford University Press
    Details
    Publication Date: 2016-11-10
    Description: The Puyehue-Cordón Caulle Volcanic Complex (PCCVC) is one of the best examples of tectonic control on volcanism at the Southern Volcanic Zone of the Andes (southern Chile). The PCCVC comprises several volcanic centres that erupted dominantly SiO 2 -rich magmas at the intersection of the trench-parallel Liquiñe-Ofqui Fault Zone (LOFZ) and an inherited NW–SE basement structure. The PCCVC began an explosive and later effusive eruption on 2011 June 4 causing decimetre- to metre-scale surface deformation that was observed by a series of Envisat ASAR satellite scenes. We modelled this data and complemented it with time-series of two continuous GPS stations and seismicity recorded by a local network. Deformation during the first 3 days of the eruption can be modelled either by two point sources aligned with the NW–SE Cordón Caulle graben or by a closing dyke with a significant component of left-lateral motion along the graben. These models are discussed with respect to their implications on the estimated rheology and the eruption mechanism. GPS observations near the volcanic complex reveal an additional, more localised effect related to the LOFZ in the south of the complex. Coeruptive deformation at the main geological structures of the PCCVC is further supported by relocated seismicity, which is concentrated along the Cordón Caulle graben and to the western side of the LOFZ.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 25
    facet.materialart.
    Unknown
    Electrical resistivity of coal-bearing rocks under high temperature and the detection of coal fires using electrical resistance tomography (2016)
    Oxford University Press
    Details
    Publication Date: 2016-01-02
    Description: Coal fires are severe hazards to environment, health and safety throughout the world. Efficient and economical extinguishing of these fires requires that the extent of the subsurface coal fires should be delineated. Electrical and electromagnetic methods have been used to detect coal fires in recent years. However, the resistivity change of coal-bearing rocks at high temperature is rarely investigated. The resistivity characteristics of coal fires at different temperatures and depths are seldomly researched as well. In this paper, we present the results of measurements of several coal-bearing rocks’ resistivity and permeability under high temperature. Two major causes for the change in resistivity with increasing temperature are recognized, there are the increase of charge carriers and thermal fracturing, of which the first one is probably the dominant cause. A set of 2-D simulations is carried out to compare the relation of resolution and efficiency of coal fires detection to temperature and depth when adopting the electrical resistance tomography. The simulation results show that the resolution and efficiency decrease with the decrease of temperature and the increase of depth. Finally, the electrical resistance tomography is used to delineate coal fires in the Anjialing Open Pit Mine. Most low-resistivity regions are verified as coal-fire areas according to the long-term monitoring of borehole temperature. The results indicate that the electrical resistance tomography can be used as a tool for the detection of coal fires.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 26
    facet.materialart.
    Unknown
    Rethinking the Water-Food-Climate Nexus and Conflict: An Opportunity Cost Approach (2016)
    Oxford University Press
    Details
    Publication Date: 2016-12-07
    Description: Much attention has been paid to the potential role that climate and food security has on conflict, especially in the Middle East. However, there has been little critical examination beyond the statistical correlation of events, which demonstrates whether a causal link exists and if it does, what can be done about it. This paper explores the conceptual linkages between food and conflict and attempts to draw attention to the opportunity cost of conflict as the nexus for decision-making in this context.
    Keywords: D74 - Conflict ; Conflict Resolution ; Alliances, Q18 - Agricultural Policy ; Food Policy, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 27
    facet.materialart.
    Unknown
    What Is the Social Value of Second Generation Biofuels? (2016)
    Oxford University Press
    Details
    Publication Date: 2016-12-07
    Description: What are second-generation (2G) biofuel technologies worth to global society? A dynamic, economic model is used to assess the impact that introducing 2G biofuels technology has on crops, livestock, biofuels, forestry, and environmental services, as well as greenhouse gas emissions. Under baseline conditions, this amounts to $64 billion and is $84 billion under the optimistic technology case, suggesting that investing in 2G technology could be appropriate. Under greenhouse gas regulation, global valuation more than doubles to $139 and $174 billion, respectively. A flat energy price scenario eliminates the value of 2G technology to society.
    Keywords: Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q42 - Alternative Energy Sources, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 28
    facet.materialart.
    Unknown
    The transient divided bar method for laboratory measurements of thermal properties (2016)
    Oxford University Press
    Details
    Publication Date: 2016-10-21
    Description: Accurate information on thermal conductivity and thermal diffusivity of materials is of central importance in relation to geoscience and engineering problems involving the transfer of heat. Several methods, including the classical divided bar technique, are available for laboratory measurements of thermal conductivity, but much fewer for thermal diffusivity. We have generalized the divided bar technique to the transient case in which thermal conductivity, volumetric heat capacity and thereby also thermal diffusivity are measured simultaneously. As the density of samples is easily determined independently, specific heat capacity can also be determined. The finite element formulation provides a flexible forward solution for heat transfer across the bar, and thermal properties are estimated by inverse Monte Carlo modelling. This methodology enables a proper quantification of experimental uncertainties on measured thermal properties and information on their origin. The developed methodology was applied to various materials, including a standard ceramic material and different rock samples, and measuring results were compared with results applying traditional steady-state divided bar and an independent line-source method. All measurements show highly consistent results and with excellent reproducibility and high accuracy. For conductivity the obtained uncertainty is typically 1–3 per cent, and for diffusivity uncertainty may be reduced to about 3–5 per cent. The main uncertainty originates from the presence of thermal contact resistance associated with the internal interfaces in the bar. These are not resolved during inversion and it is imperative that they are minimized. The proposed procedure is simple and may quite easily be implemented to the many steady-state divided bar systems in operation. A thermally controlled bath, as applied here, may not be needed. Simpler systems, such as applying temperature-controlled water directly from a tap, may also be applied.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 29
    facet.materialart.
    Unknown
    Trade Liberalization versus Climate Change Policy for Reducing Greenhouse Gas Emissions in Agriculture: Some Insights from Norway (2015)
    Oxford University Press
    Details
    Publication Date: 2015-08-11
    Description: Using a mathematical programming model of Norwegian agriculture, we explore interconnections between trade liberalization and reductions in greenhouse gas (GHG) emissions. We show that the Doha Round proposals for a new agreement on agriculture through the World Trade Organization would not generate significant reductions in emissions. Further trade liberalization would reduce emissions by cutting agricultural production but would not change production methods. Imposing a carbon tax would lead both to a reduction in output and the extensification of production. In contrast, if farmers are allowed to claim a credit for carbon sequestration the effect is to intensify agricultural production.
    Keywords: F18 - Trade and Environment, Q17 - Agriculture in International Trade, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 2040-5790
    Electronic ISSN: 2040-5804
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 30
    facet.materialart.
    Unknown
    The collapse of Bartharbunga caldera, Iceland (2015)
    Oxford University Press
    Details
    Publication Date: 2015-05-10
    Description: Lying below Vatnajökull ice cap in Iceland, Bárðarbunga stratovolcano began experiencing wholesale caldera collapse in 2014 August 16, one of the largest such events recorded in the modern instrumental era. Simultaneous with this collapse is the initiation of a plate boundary rifting episode north of the caldera. Observations using the international constellation of radar satellites indicate rapid 50 cm d –1 subsidence of the glacier surface overlying the collapsing caldera and metre-scale crustal deformation in the active rift zone. Anomalous earthquakes around the rim of the caldera with highly nondouble-couple focal mechanisms provide a mechanical link to the dynamics of the collapsing magma chamber. A model of the collapse consistent with available geodetic and seismic observations suggests that the majority of the observed subsidence occurs aseismically via a deflating sill-like magma chamber.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 31
    facet.materialart.
    Unknown
    Melt-band instabilities with two-phase damage (2015)
    Oxford University Press
    Details
    Publication Date: 2015-03-11
    Description: Deformation experiments on partially molten rocks in simple shear form melt bands at 20° to the shear plane instead of at the expected 45° principal compressive stress direction. These melt bands may play an important role in melt focusing in mid-ocean ridges. Such shallow bands are known to form for two-phase media under shear if strongly non-Newtonian power-law creep is employed for the solid phase, or anisotropy imposed. However laboratory experiments show that shallow bands occur regardless of creep mechanism, even in diffusion creep, which is nominally Newtonian. Here we propose that a couple of forms of two-phase damage allow for shallow melt bands even in diffusion creep.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 32
    facet.materialart.
    Unknown
    Local warming and violent conflict in North and South Sudan (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-14
    Description: Our article contributes to the emerging micro-level strand of the literature on the link between local variations in weather shocks and conflicts by focusing on a pixel-level analysis for North and South Sudan between 1997 and 2009. Temperature anomalies are found to strongly affect the risk of conflict, whereas the risk is expected to magnify in a range of 24–31% in the future under a median scenario. Our analysis also sheds light on the competition over natural resources, in particular water, as the main driver of such relationship in a region where pastoralism constitutes the dominant livelihood.
    Keywords: D74 - Conflict ; Conflict Resolution ; Alliances, O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products, Q54 - Climate ; Natural Disasters ; Global Warming, R11 - Regional Economic Activity: Growth, Development, and Changes
    Print ISSN: 1468-2702
    Electronic ISSN: 1468-2710
    Topics: Geography , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 33
    facet.materialart.
    Unknown
    Dealing with Uncertainty in Agent-Based Simulation: Farm-Level Modeling of Adaptation to Climate Change in Southwest Germany (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-18
    Description: Climate change will most likely confront agricultural producers with natural, economic, and political conditions that have not previously been observed and are largely uncertain. As a consequence, extrapolation from past data reaches its limits, and a process-based analysis of farmer adaptation is required. Simulation of changes in crop yields using crop growth models is a first step in that direction. However, changes in crop yields are only one pathway through which climate change affects agricultural production. A meaningful process-based analysis of farmer adaptation requires a whole-farm analysis at the farm level. We use a highly disaggregated mathematical programming model to analyze farm-level climate change adaptation for a mountainous area in southwest Germany. Regional-level results are obtained by simulating each full-time farm holding in the study area. We address parameter uncertainty and model underdetermination using a cautious calibration approach and a comprehensive uncertainty analysis. We deal with the resulting computational burden using efficient experimental designs and high-performance computing. We show that in our study area, shifted crop management time slots can have potentially significant effects on agricultural supply, incomes, and various policy objectives promoted under German and European environmental policy schemes. The simulated effects are robust against model uncertainty and underline the importance of a comprehensive assessment of climate change impacts beyond merely looking at crop yield changes. Our simulations demonstrate how farm-level models can contribute to a process-based analysis of climate change adaptation if they are embedded into a systematic framework for treating inherent model uncertainty.
    Keywords: C61 - Optimization Techniques ; Programming Models ; Dynamic Analysis, C63 - Computational Techniques, Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 34
    facet.materialart.
    Unknown
    Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants (2015)
    Oxford University Press
    Details
    Publication Date: 2015-12-13
    Description: This article uses the 2007 Farm and Ranch Irrigation Survey database developed by the U.S. Department of Agriculture to assess the impact of water scarcity and climate on irrigation decisions for producers of specialty crops, wheat, and forage crops. We estimate an irrigation management model for major crops in the West Coast (California, Oregon, and Washington), which includes a farm-level equation of irrigated share and crop-specific equations of technology adoption and water application rate (orchard/vineyard, vegetable, wheat, alfalfa, hay, and pasture). We find that economic and physical water scarcity, climate, and extreme weather, such as frost, extreme heat, and drought, significantly impact producers’ irrigation decisions. Producers use sprinkler technologies or additional water applications to mitigate risk of crop damage from extreme weather. Water application rates are least responsive to surface water cost or groundwater well depth for producers of orchard/vineyard. Water supply institutions influence producers’ irrigation decisions. Producers who receive water from federal agencies use higher water application rates and are less likely to adopt water-saving irrigation technologies for some crops. Institutional arrangements, including access to distinct water sources (surface or ground) and whether surface water cost is fee based, also affect the responsiveness of water application rates to changes in surface water cost. The analysis provides valuable information about how producers in irrigated agricultural production systems would respond and adapt to water pricing policies and climate change.
    Keywords: Q12 - Micro Analysis of Farm Firms, Farm Households, and Farm Input Markets, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q16 - R&D ; Agricultural Technology ; Agricultural Extension Services, Q18 - Agricultural Policy ; Food Policy, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 35
    facet.materialart.
    Unknown
    An Introduction to the Green Paradox: The Unintended Consequences of Climate Policies (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-18
    Description: How important is the Green Paradox? We address this question in three ways. First, we present a simple model explaining how announcing a future climate policy may increase carbon emissions today – the Green Paradox effect. This effect is a result of fossil fuel producers increasing their extraction today as a response to a reduction in future resource rents. Second, we examine the theoretical and empirical literature to assess whether green paradoxes are likely to occur, and if they are, whether they are big enough to be of concern for policy makers. We consider several factors that affect the existence of the green paradox, including long-term extraction costs, short-term extraction capacities, the mix of policy instruments, and potential spatial carbon leakage to countries that have no climate policy. We find that these and other factors can sometimes strengthen, but mostly weaken, the case for concern about the green paradox. Third, we identify the lessons the literature offers for policy makers. We argue that in designing climate policy, policy makers need to consider the supply side of the fossil fuel market.
    Keywords: H23 - Externalities ; Redistributive Effects ; Environmental Taxes and Subsidies, Q31 - Demand and Supply, Q38 - Government Policy, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 36
    facet.materialart.
    Unknown
    Introductory Comment-The Green Paradox: A Supply-Side View of the Climate Problem (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-18
    Description: Why have policies aimed at reducing the demand for carbon not succeeded in slowing down global carbon extraction and CO 2 emissions, and why have carbon prices failed to increase over the last three decades? This comment argues that this is because of the Green Paradox, that is, the anticipation of sales by resource owners who try to preempt the destruction of their markets by green policies. Reviewing some of the conditions under which strong and weak versions of the Green Paradox may emerge, it is argued that there is little hope that green replacement technologies will impose hard price constraints that would keep long-run extraction within a fixed carbon budget and that, therefore, even strong versions of the paradox cannot easily be avoided.
    Keywords: O13 - Agriculture ; Natural Resources ; Energy ; Environment ; Other Primary Products, Q32 - Exhaustible Resources and Economic Development, Q54 - Climate ; Natural Disasters ; Global Warming, H23 - Externalities ; Redistributive Effects ; Environmental Taxes and Subsidies
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 37
    facet.materialart.
    Unknown
    The Green Paradox in Open Economies: Lessons from Static and Dynamic Models (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-18
    Description: This article examines how, in a world with incomplete coordination among countries, well-intentioned unilateral environmental policies may actually harm the global environment. This outcome is known as the "Green Paradox." The incentives for free-riding and the challenge of achieving an effective international environmental agreement are reviewed. I examine the various channels that lead to carbon leakage in static models of open economies, and report some simulation results. This is complemented by a review of the potential for Green Paradox outcomes in dynamic open-economy models in which forward-looking firms exploit an exhaustible resource. I show that border tax adjustments can lead to Green Paradox outcomes. I also discuss priorities for future research on environmental policies in a trading world that lacks a central enforcement agency.
    Keywords: Q54 - Climate ; Natural Disasters ; Global Warming, Q42 - Alternative Energy Sources
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 38
    facet.materialart.
    Unknown
    Reflections-Managing Uncertain Climates: Some Guidance for Policy Makers and Researchers (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-18
    Description: Climate change—and, by extension, climate policy—is beset with unknowns and unknowables. This "Reflections" article presents an overview of approaches to managing climate uncertainties, in the hopes of providing guidance for current policy decisions as well as future research. We propose the following guidance for policy makers: Treat climate change as a risk management problem; recognize that benefit-cost analysis is only the first of many steps in deciding on optimal climate policy; in assessing abatement choices, use a discount rate that declines over time; recognize the importance of framing, evidence, and connecting the dots; reward modesty. We suggest the following questions for consideration by researchers: Can we improve forecasting? Can we improve the way we address nonlinearities and possible irreversibilities? What other (sub)disciplines merit a closer look? How can we create the right incentives for updating and expanding economic damage functions and climate-economy models? What alternative decision criteria merit further exploration? What does ‘not knowing’ tell us?
    Keywords: Q54 - Climate ; Natural Disasters ; Global Warming, D81 - Criteria for Decision-Making under Risk and Uncertainty
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 39
    facet.materialart.
    Unknown
    Analytical parametrization of self-consistent polycrystal mechanics: Fast calculation of upper mantle anisotropy (2015)
    Oxford University Press
    Details
    Publication Date: 2015-08-29
    Description: Progressive deformation of upper mantle rocks via dislocation creep causes their constituent crystals to take on a non-random orientation distribution (crystallographic preferred orientation or CPO) whose observable signatures include shear-wave splitting and azimuthal dependence of surface wave speeds. Comparison of these signatures with mantle flow models thus allows mantle dynamics to be unraveled on global and regional scales. However, existing self-consistent models of CPO evolution are computationally expensive when used with 3-D and/or time-dependent convection models. Here we propose a new method, called ANPAR, which is based on an analytical parametrization of the crystallographic spin predicted by the second-order (SO) self-consistent theory. Our parametrization runs 2–6  x  10 4 times faster than the SO model and fits its predictions for CPO and crystallographic spin with a variance reduction 〉99 per cent. We illustrate the ANPAR model predictions for the deformation of olivine with three dominant slip systems, (010)[100], (001)[100] and (010)[001], for three uniform deformations (uniaxial compression, pure shear and simple shear) and for a corner-flow model of a spreading mid-ocean ridge.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 40
    facet.materialart.
    Unknown
    Imaging volcanic infrasound sources using time reversal mirror algorithm (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-11
    Description: We investigate the capability of Time Reversal Mirror (TRM) algorithm to image local acoustic sources (〈3.5 km) associated with complex, sustained volcanic eruptions. Accurate source localization for volcano infrasound (low-frequency acoustic waves) is often challenging due to pronounced volcanic topography and emergent arrivals of infrasound signals. While the accuracy of the conventional approaches (e.g. triangulation and semblance method) can be severely compromised by the complex volcanic settings, a TRM-based method may have the potential to properly image acoustic sources by the use of full waveform information and numerical modelling of the time-reversed wavefield. We apply the TRM algorithm to a pyroclastic-laden eruption (sustained for ~60 s) at Santiaguito Volcano, Guatemala, and show that an ordinary TRM operation can undergo significant reduction of its focusing power due to strong topographic propagation effects (e.g. reflection and diffraction). We propose a weighted imaging condition to compensate for complicated transmission loss of the time-reversed wavefield and demonstrate that the presented condition significantly improves the focusing quality of TRM in the presence of complex topography. The consequent TRM source images exhibit remarkable agreement with the visual observation of the eruption implying that the TRM method with a proper imaging condition can be used to localize and track acoustic sources associated with complex volcanic eruptions.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 41
    facet.materialart.
    Unknown
    The Effect of Weather-Induced Internal Migration on Local Labor Markets. Evidence from Uganda (2015)
    Oxford University Press
    Details
    Publication Date: 2015-05-21
    Description: Relying on census data collected in 2002 and historical weather data for Uganda, we estimate the impact of weather-induced internal migration on the probability for non-migrants living in the destination regions to be employed. Consistent with the prediction of a simple theoretical model, our results reveal a larger negative impact than the one documented for developed countries. They further show that this negative impact is significantly stronger in Ugandan regions with lower road density and therefore less conducive to capital mobility: a 10 percentage points increase in the net in-migration rate in these areas decreases the probability of being employed of non-migrants by more than 10 percentage points.
    Keywords: E24 - Employment ; Unemployment ; Wages ; Intergenerational Income Distribution, J21 - Labor Force and Employment, Size, and Structure, J61 - Geographic Labor Mobility ; Immigrant Workers, Q54 - Climate ; Natural Disasters ; Global Warming, R23 - Regional Migration ; Regional Labor Markets ; Population
    Print ISSN: 0258-6770
    Electronic ISSN: 1564-698X
    Topics: Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 42
    facet.materialart.
    Unknown
    A strategy to explore the topography-driven distortions in the tilt field induced by a spherical pressure source: the case of Mt Etna (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-12
    Description: We present a strategy to thoroughly investigate the effects of prominent topography on the surface tilt due to a spherical pressure source. We use Etna's topography as a case of study and, for different source positions, we compare the tilt fields calculated through (i) a 3-D boundary element method and (ii) analytical half-space solutions. We systematically determine (i) the source positions leading to the strongest tilt misfits when numerical and analytical results are compared and (ii) the surface areas where the strongest distortions in the tilt field are most likely to be observed. We also demonstrate that, under critical circumstances, in terms of respective positions of pressure source and observation points, results of inversion procedures aimed at retrieving the source parameters can be misleading, if tilt data are analysed using models that do not account for topography.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 43
    facet.materialart.
    Unknown
    Optimal Directions for Directional Distance Functions: An Exploration of Potential Reductions of Greenhouse Gases (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-18
    Description: This article explores the reduction potential of greenhouse gases for major pollution-emitting countries of the world using nonparametric productivity measurement methods and directional distance functions. In contrast to the existing literature, we apply optimization methods to endogenously determine optimal directions for the efficiency analysis. These directions represent the compromise of output enhancement and emissions reduction. The results show that for reasonable directions the adoption of best practices would lead to sizable emission reductions in a range of approximately 20% compared with current levels.
    Keywords: C14 - Semiparametric and Nonparametric Methods, D24 - Production ; Cost ; Capital and Total Factor Productivity ; Capacity, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 44
    facet.materialart.
    Unknown
    The elastic properties and stability of fcc-Fe and fcc-FeNi alloys at inner-core conditions (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-24
    Description: The agreement between shear wave velocities for the Earth's inner core observed from seismology with those derived from mineral physics is considerably worse than for any other region of the Earth. Furthermore, there is still debate as to the phase of iron present in the inner core, particularly when alloying with nickel and light elements is taken into account. To investigate the extent to which the mismatch between seismology and mineral physics is a function of either crystal structure and/or the amount of nickel present, we have used ab initio molecular dynamics simulations to calculate the elastic constants and seismic velocities ( V p and V s ) of face centred cubic (fcc) iron at Earth's inner core pressures (360 GPa) and at temperatures up to ~7000 K. We find that V p for fcc iron (fcc-Fe) is very similar to that for hexagonal close packed (hcp) iron at all temperatures. In contrast, V s for fcc-Fe is significantly higher than in hcp-Fe, with the difference increasing with increasing temperature; the difference between V s for the core (from seismology) and V s for fcc-Fe exceeds 40 per cent. These results are consistent with previous work at lower temperatures. We have also investigated the effect of 6.5 and 13 atm% Ni in fcc-Fe. We find that Ni only slightly reduces V p and V s (e.g. by 2 per cent in V s for 13 atm% Ni at 5500 K), and cannot account for the difference between the velocities observed in the core and those of pure fcc-Fe. We also tried to examine pre-melting behaviour in fcc-Fe, as reported in hcp-Fe by extending the study to very high temperatures (at which superheating may occur). However, we find that fcc-Fe spontaneously transforms to other hcp-like structures before melting; two hcp-like structures were found, both of hexagonal symmetry, which may most easily be regarded as being derived from an hcp crystal with stacking faults. That the structure did not transform to a true hcp phase is likely as a consequence of the limited size of the simulation box (108 atoms). At 360 GPa, in pure fcc-Fe, we find that the transition from fcc to the hcp-like structure occurs at 7000 K, whereas in the Ni bearing system, the transition occurs at higher temperature (7250 K). This reinforces previous work showing that fcc-Fe might transform to hcp-Fe just before melting, and that Ni tends to stabilize the fcc structure with respect to hcp.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 45
    facet.materialart.
    Unknown
    Time-dependent displacement and stress fields due to shear and tensile faults in a transversely isotropic viscoelastic half-space (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-25
    Description: Viscoelastic behaviour of materials in nature is observed in post-event deformations due to seismic or volcanic activities. In this paper, by adopting the correspondence principle, we propose an inelastic model to predict first the Laplace-domain response of a transversely isotropic viscoelastic half-space due to a shear or tensile fault of polygonal shape. The displacement and stress fields in the time domain are then obtained using an efficient and accurate algorithm for the inverse Laplace transform. Numerical examples are presented to validate the proposed solution and to show the viscoelastic displacement and stress fields due to a strike-slip, dip-slip and tensile fault of rectangular shape. The obtained results indicate that both viscoelasticity and transverse isotropy play significant roles in the viscoelastic response of the half-space due to faults, which could be used as benchmarks for the future numerical analysis of realistic post-seismic or volcanic event.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 46
    facet.materialart.
    Unknown
    Scaling of viscous shear zones with depth-dependent viscosity and power-law stress-strain-rate dependence (2015)
    Oxford University Press
    Details
    Publication Date: 2015-04-26
    Description: One of the unresolved questions concerning fault deformation is the degree and cause of localization of shear at depth beneath a fault. Geologic observations of exhumed shear zones indicate that while the motion is no longer planar, it can still be localized near the down-dip extension of the fault; however, the degree of localization is uncertain. We employ simple analytic and numerical models to investigate the structural form of distributed shear beneath a strike-slip fault, and the relative importance of the physical mechanisms that have the potential to localize a shear zone. For a purely depth dependent viscosity, = 0 exp (– z / z 0 ), we find that a shear zone develops with a half-width $\delta _w\sim \sqrt{z_0}$ for small z 0 at the base of the layer, where lengths are non-dimensionalized by the layer thickness ( d km). Including a non-linear stress–strain-rate relation ( $\dot{\epsilon }\propto \sigma ^n$ ) scales w by $1/\sqrt{n}$ , comparable to deformation length scales in thin viscous sheet calculations. We find that the primary control on the shear-zone width is the depth dependence of viscosity that arises from the temperature dependence of viscosity and the increase in temperature with depth. As this relationship is exponential, scaling relations give a dimensional half-width that scales approximately as $$ \tilde{\delta }_w\approx T_{\frac{1}{2}}\sqrt{\frac{Rd}{nQ\beta }}\text{ km}, $$ where $T_{\frac{1}{2}}$ (K) is the temperature at the midpoint of the layer, R (J mol –1 K –1 ) the gas constant, Q (J mol –1 ) the activation energy and β (K km –1 ) the geothermal gradient. This relation predicts the numerical results for the parameter range consistent with continental rheologies to within 2–5 per cent and shear-zone half-widths from 2 to 6 km. The inclusion of shear-stress heating reduces w by only an additional 5–25 per cent, depending on the initial width of the shear zone. While the width of the shear zone may not decrease significantly, local temperature increases from shear-stress heating range from 50 to 300 °C resulting in a reduction in viscosities beneath the fault of several orders of magnitude and a concomitant reduction in the stresses needed to drive the motion.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 47
    facet.materialart.
    Unknown
    Regulation of Natural Gas in the United States, Canada, and Europe: Prospects for a Low Carbon Fuel (2015)
    Oxford University Press
    Details
    Publication Date: 2015-01-29
    Description: The United States and Canada have seen a competitive and technological revolution in unconventional natural gas production in the 21 st Century—dramatically lowering the price of gas and displacing high-carbon coal with low-carbon gas for power generation. This gas revolution came from an earlier revolution in the regulation of gas pipelines, which ended the obstruction of gas markets by pipeline interests. Neither revolution has spread to Europe, where increasingly protectionist EU legislation has effectively blocked competitive pipeline entry and related gas markets. As a result, unconventional gas is untapped, coal displaces gas for power generation, and oil-linked gas prices have cost EU consumers a staggering $425 billion more than their US counterparts have paid since 2009 for about the same quantity of gas. Europe faces a serious institutional challenge to adopting the kind of pipeline regulation that facilitates the competitive flow of natural gas supplies and the accompanying lower carbon emissions. ( JEL : D23, K23, L14, L51, L95, N70, Q54)
    Keywords: D23 - Organizational Behavior ; Transaction Costs ; Property Rights, K23 - Regulated Industries and Administrative Law, L14 - Transactional Relationships ; Contracts and Reputation ; Networks, L51 - Economics of Regulation, L95 - Gas Utilities ; Pipelines ; Water Utilities, N70 - General, International, or Comparative, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 48
    facet.materialart.
    Unknown
    A Global Perspective on the Future of Natural Gas: Resources, Trade, and Climate Constraints (2015)
    Oxford University Press
    Details
    Publication Date: 2015-01-29
    Description: Natural gas plays an important role in the global energy system as an input to power generation, heating, and industry. This article identifies key drivers and uncertainties for natural gas markets in the coming decades. These include the availability of natural gas from conventional and unconventional sources, the role of international trade, and the impact of climate policies. We build on model-based research as well as an up-to-date survey of natural gas resource availability. We find that natural gas is an abundant fossil fuel and that the Asia-Pacific region will be most important in future global natural gas markets, especially under stringent international climate change mitigation. This means that an increasingly large share of future natural gas trade flows and infrastructure expansions will be directed to the Asia-Pacific region and that the role of liquefied natural gas will continue to increase globally. ( JEL : C61, L71, Q33, Q37, Q54)
    Keywords: C61 - Optimization Techniques ; Programming Models ; Dynamic Analysis, L71 - Mining, Extraction, and Refining: Hydrocarbon Fuels, Q33 - Resource Booms, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 1750-6816
    Electronic ISSN: 1750-6824
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Political Science , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 49
    facet.materialart.
    Unknown
    Fiscal Responses after Catastrophes and the Enabling Role of Financial Development (2015)
    Oxford University Press
    Details
    Publication Date: 2015-01-29
    Description: Natural disasters may constitute a major shock to public finances and debt sustainability because of their impact on output and the need for government response with reconstruction and relief expenses. The question arises of whether governments can use financial development policy as the means to mitigate or insure against this negative fiscal impact. This paper uses a panel vector autoregressive model, estimated on annual data for high- and middle-income countries over 1975–2008, to study the role of debt market development and insurance penetration in enabling fiscal response after catastrophes. The authors find that countries with higher debt market development suffer smaller real consequences from disasters but that their deficits expand further following the mitigating fiscal response. Disasters in countries with high insurance penetration also experience smaller real consequences of disasters but without the need for further deficit expansions. From an ex-post perspective, the availability of insurance could offer the best mitigation approach against the real and fiscal consequences of disasters.
    Keywords: E32 - Business Fluctuations ; Cycles, H50 - General, H60 - General, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0258-6770
    Electronic ISSN: 1564-698X
    Topics: Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 50
    facet.materialart.
    Unknown
    On the use of thermal equations of state and the extrapolation at high temperature and pressure for geophysical and petrological applications (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-09
    Description: The equation that relates pressure, temperature and volume and is described by parameters that are function of temperature at 1 bar (hereafter called thermal equation of state, TEOS), has practical computational advantages for petrological and geophysical applications over the equation that considers explicitly a thermal pressure. Some considerations that justify the use of the TEOS are discussed here. (1) The assumption that the parameters are function of temperature is perhaps better understood by looking at the Helmholtz energy function that is implicitly assumed in the case of an equation of state (EOS) derived from interatomic potentials. A test case shows that the Helmholtz energy related to the Vinet EOS and the Helmholtz energy from the Debye model are very similar. (2) The TEOS should be able to reproduce thermal expansion (α), isothermal bulk modulus ( K T ) and heat capacity ( C p and C v ) at high P , T computed from a lattice vibration model. The generalized Rydberg EOS applied to MgO is able to fit reasonably well the properties computed using Jacobs’ lattice dynamics formulation ( T range = 300–3000 K, P range = 1 bar–1500 kbar). (3) It is shown that in the case of MgO, the TEOS can be used quite successfully for extrapolation that goes beyond the P , T range of the measured/given data. Some physical constraints need to be applied to the derivation of the volume, bulk modulus and derivative of the bulk modulus with pressure at 1 bar. (4) The pressure dependence of the reference parameters in the TEOS that was inferred several decades ago is only apparent. A numerical computation demonstrates that the combined pressure effect in the terms defining the partial derivative of the reference V and K (and K') over temperature cancels out, making the reference parameters independent of pressure at any condition.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 51
    facet.materialart.
    Unknown
    Distributional Implications of Climate Change in Rural India: A General Equilibrium Approach (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-10
    Description: We develop a general equilibrium framework, based on a specific-factors trade model, to quantify the medium-term household welfare impacts of global warming in rural India. Using an hedonic approach grounded in the theory combined with detailed microdata, we estimate that three decades of warming will reduce agricultural productivity in the range of 7%–13%, with the arid northwest of India especially hard hit. Our analysis shows that the proportional welfare cost of climate change is likely to be both modest and evenly distributed across percentiles of the per capita income distribution, but this latter conclusion emerges only when the flexibility of rural wages is taken into account.
    Keywords: Q17 - Agriculture in International Trade, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 52
    facet.materialart.
    Unknown
    On the use of thermal equations of state and the extrapolation at high temperature and pressure for geophysical and petrological applications (2015)
    Oxford University Press
    Details
    Publication Date: 2015-07-17
    Description: The equation that relates pressure, temperature and volume and is described by parameters that are function of temperature at 1 bar (hereafter called thermal equation of state, TEOS), has practical computational advantages for petrological and geophysical applications over the equation that considers explicitly a thermal pressure. Some considerations that justify the use of the TEOS are discussed here. (1) The assumption that the parameters are function of temperature is perhaps better understood by looking at the Helmholtz energy function that is implicitly assumed in the case of an equation of state (EOS) derived from interatomic potentials. A test case shows that the Helmholtz energy related to the Vinet EOS and the Helmholtz energy from the Debye model are very similar. (2) The TEOS should be able to reproduce thermal expansion (α), isothermal bulk modulus ( K T ) and heat capacity ( C p and C v ) at high P , T computed from a lattice vibration model. The generalized Rydberg EOS applied to MgO is able to fit reasonably well the properties computed using Jacobs’ lattice dynamics formulation ( T range = 300–3000 K, P range = 1 bar–1500 kbar). (3) It is shown that in the case of MgO, the TEOS can be used quite successfully for extrapolation that goes beyond the P , T range of the measured/given data. Some physical constraints need to be applied to the derivation of the volume, bulk modulus and derivative of the bulk modulus with pressure at 1 bar. (4) The pressure dependence of the reference parameters in the TEOS that was inferred several decades ago is only apparent. A numerical computation demonstrates that the combined pressure effect in the terms defining the partial derivative of the reference V and K (and K') over temperature cancels out, making the reference parameters independent of pressure at any condition.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 53
    facet.materialart.
    Unknown
    A Green's function approach for assessing the thermal disturbance caused by drilling deep boreholes in rock or ice (2015)
    Oxford University Press
    Details
    Publication Date: 2015-10-30
    Description: A knowledge of subsurface temperatures in sedimentary basins, fault zones, volcanic environments and polar ice sheets is of interest for a wide variety of geophysical applications. However, the process of drilling deep boreholes in these environments to provide access for temperature and other measurements invariably disturbs the temperature field around a newly created borehole. Although this disturbance dissipates over time, most temperature measurements are made while the temperature field is still disturbed. Thus, the measurements must be ‘corrected’ for the drilling-disturbance effect if the undisturbed temperature field is to be determined. This paper provides compact analytical solutions for the thermal drilling disturbance based on 1-D (radial) and 2-D (radial and depth) Green's functions (GFs) in cylindrical coordinates. Solutions are developed for three types of boundary conditions (BCs) at the borehole wall: (1) prescribed temperature, (2) prescribed heat flux and (3) a prescribed convective condition. The BC at the borehole wall is allowed to vary both with depth and time. Inclusion of the depth dimension in the 2-D solution allows vertical heat-transfer effects to be quantified in situations where they are potentially important, that is, near the earth's surface, at the bottom of a well and when considering finite-drilling rates. The 2-D solution also includes a radial- and time-dependent BC at the earth's surface to assess the impact of drilling-related infrastructure (drilling pads, mud pits, permanent shelters) on the subsurface temperature field. Latent-heat effects due to the melting and subsequent refreezing of interstitial ice while drilling a borehole through ice-rich permafrost can be included in the GF solution as a moving-plane heat source (or sink) located at the solid–liquid interface. Synthetic examples are provided illustrating the 1-D and 2-D GF solutions. The flexibility of the approach allows the investigation of thermal drilling effects in rock or ice for a wide variety of drilling technologies. Numerical values for the required radial GFs G R are available through the Advanced Cooperative Arctic Data and Information Service at doi:10.5065/D64F1NS6.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 54
    facet.materialart.
    Unknown
    Responsiveness of Crop Yield and Acreage to Prices and Climate (2015)
    Oxford University Press
    Details
    Publication Date: 2015-12-13
    Description: We investigate the effect of crop price and climate variables on rainfed corn and soybean yields and acreage in the United States using a large panel dataset for the 1977–2007 period. Instrumental variables are used to control for endogeneity of prices in yield and acreage regressions, while allowing for spatially auto-correlated errors. We find that an increase in corn price has a statistically significant positive impact on corn yield, but the effect of soybean price on soybean yields is not statistically significant. The estimated price elasticities of corn yield and acreage are 0.23 and 0.45, respectively. Of the increase in corn supply caused by an increase in corn price, we find that 33.8% is due to price-induced yield enhancement and 66.2% is due to price-induced acreage expansion. We also find that the impact of climate change on corn production ranges from $-$ 7% to $-$ 41% and on soybean ranges from $-$ 8% to $-$ 45%, depending on the climate change scenarios, time horizon, and global climate models used to predict climate change. We show that the aggregate net impact of omitting price variables is an overestimation of the effect of climate change on corn yield by up to 9% and on soybean yield by up to 15%.
    Keywords: Q11 - Aggregate Supply and Demand Analysis ; Prices, Q15 - Land Ownership and Tenure ; Land Reform ; Land Use ; Irrigation, Q54 - Climate ; Natural Disasters ; Global Warming
    Print ISSN: 0002-9092
    Electronic ISSN: 1467-8276
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Economics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 55
    facet.materialart.
    Unknown
    New heat flow determination in northern Tarim Craton, northwest China (2015)
    Oxford University Press
    Details
    Publication Date: 2015-01-08
    Description: Tarim Craton is a Precambrian block situated in northwest China, just north of the Tibetan Plateau, where a large sedimentary basin with abundant hydrocarbon potential has developed. Accurate heat flow data for Tarim is vital for understanding the lithospheric evolution and hydrocarbon generation in this area; however, there were unavailable until now, due to a lack of high quality steady-state temperature logging data. Here, we report 10 new heat flow values derived from steady-state temperature logging and measured thermal conductivity data. New heat flow values range from 40.1 to 49.4 mW m –2 , with a mean of 43.1 ± 3.0 mW m –2 . In addition, radiogenic heat production from the sediments accounts for 20 per cent of the observed surface heat flow, whilst the mantle heat flow is estimated to be as low as 6–15 mW m –2 ; this indicates a dominant contribution from crustal heat, to the observed heat flow. The average heat flow and crustal temperature in the Tarim Craton are markedly lower than those in the Tibetan Plateau, whilst the calculated rheological strength of the lithosphere, beneath Tarim, is sufficiently large to resist the elevation-induced gravitational potential energy difference between Tarim and Tibet. This inherited thermal and rheological contrast, between the craton and Plateau, can be traced back to before the India–Asia collision; this accounts for the differential active deformation pattern in the Tarim Craton and adjacent areas.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 56
    facet.materialart.
    Unknown
    Calculation of thermal conductivity, thermal diffusivity and specific heat capacity of sedimentary rocks using petrophysical well logs (2015)
    Oxford University Press
    Details
    Publication Date: 2015-11-05
    Description: In this study, equations are developed that predict for synthetic sedimentary rocks (clastics, carbonates and evapourates) thermal properties comprising thermal conductivity, specific heat capacity and thermal diffusivity. The rock groups are composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities of 0–30 per cent. Petrophysical properties and their well-logging-tool-characteristic readings were assigned to these rock-forming minerals and to pore-filling fluids. Relationships are explored between each thermal property and other petrophysical properties (density, sonic interval transit time, hydrogen index, volume fraction of shale and photoelectric absorption index) using multivariate statistics. The application of these relations allows computing continuous borehole profiles for each rock thermal property. The uncertainties in the prediction of each property vary depending on the selected well-log combination. Best prediction is in the range of 2–8 per cent for the specific heat capacity, of 5–10 per cent for the thermal conductivity, and of 8–15 for the thermal diffusivity, respectively. Well-log derived thermal conductivity is validated by laboratory data measured on cores from deep boreholes of the Danish Basin, the North German Basin, and the Molasse Basin. Additional validation of thermal conductivity was performed by comparing predicted and measured temperature logs. The maximum deviation between these logs is 〈3 °C. The thermal-conductivity calculation allowed an evaluation of the depth range in which the palaeoclimatic effect on the subsurface temperature field can be observed in the North German Basin. This effect reduces the surface heat-flow density by 25 mW m –2 .
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 57
    facet.materialart.
    Unknown
    Electrokinetic experimental study on saturated rock samples: zeta potential and surface conductance (2015)
    Oxford University Press
    Details
    Publication Date: 2015-03-18
    Description: It is important to know the electrokinetic properties of crustal rocks for interpreting the conductivity mechanisms and seismoelectric phenomena during earthquakes and seismoelectric well logging. In this study, electrokinetic experiments are conducted using a special core-holder by employing an AC lock-in technique. A series of experiments are conducted on 10 sandstone samples to measure the streaming potentials and streaming currents, and the experiments on each sample are done at six different salinities. The streaming potential coefficient and streaming current coefficient are calculated from the measured streaming potentials and streaming currents. The experimental results show that streaming potential coefficient and streaming current coefficient decrease as the salinity increases. The dependence of these two coefficients on permeability and pore radius are analysed and compared with previous works. At low salinities, the streaming potential coefficient and streaming current coefficient increase with the increasing permeability and pore radius. At high salinities, the streaming potential coefficient (streaming current coefficient) almost share a same value for 10 different samples. This conclusion indicates that the differences of rock parameters can only be well recognized at lower salinities, and the electrokinetic signals are invalid at high salinities, which offers a restrictive condition for using the amplitude of electrokinetic signals to estimate rock parameters. The zeta-potential have also been estimated through combined measurements of streaming potential and streaming current. The surface conductivity and its contribution to electrokinetic effects are determined from a comparison of zeta-potentials by two different methods, and then the validation of the Helmholz–Smoluchowski equation for a capillary tube is tested in rocks. We also compare our date with theoretical and experimental works, and set up an expression about the relationship between zeta potential and salinity, which fits the experimental data well.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 58
    facet.materialart.
    Unknown
    Elastic properties of ferrous bearing MgSiO3 and their relevance to ULVZs (2015)
    Oxford University Press
    Details
    Publication Date: 2015-03-04
    Description: We used ab initio molecular dynamics to calculate the elastic constants of MgSiO 3 , FeSiO 3 and (Fe 0.5 Mg 0.5 )SiO 3 perovskite under lower-most mantle conditions (136 GPa, 2000–4000 K). At 0 K, V p and V s for FeSiO 3 perovskite are 12 and 18 per cent lower, respectively than those for MgSiO 3 , in agreement with previous work. The difference in velocity, however, increases with temperature for high spin (but not low spin) states and at 4000 K, V p and V s for the end-member FeSiO 3 are, respectively, 19 and 34 per cent lower than those of MgSiO 3 . We find that (dln V s /dln V p ) T,P of Fe x Mg 1- x O 3 remains below 2 for all relevant iron concentrations and lower than the value of 3 seen in most ultralow velocity zones (ULVZ). Moreover, we are unable to match simultaneously the observed density increase and shear wave velocity reduction shown by ULVZs by increasing the ferrous iron content in perovskite except for the largest density increases and the smallest shear wave decreases observed in ULVZs. Assuming that current seismic estimates of ULVZ properties are accurate, our results suggest that ferrous iron enrichment alone cannot explain ULVZs.
    Keywords: Mineral Physics, Rheology, Heat Flow and Volcanology
    Print ISSN: 0956-540X
    Electronic ISSN: 1365-246X
    Topics: Geosciences
    Published by Oxford University Press on behalf of The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...