Accommodating migration to promote adaptation to climate change

This paper explains how climate change may increase future migration, and which risks are associated with such migration. It also examines how some of this migration may enhance the capacity of communities to adapt to climate change. Climate change is likely to result in some increase above baseline rates of migration in the next 40 years. Most of this migration will occur within developing countries. There is little reason to think that such migration will increase the risk of violent conflict. Not all movements in response to climate change will have negative outcomes for the people that move, or the places they come from and go to. Migration, a proven development strategy, can increase the capacity of communities to adapt to climate change. The fewer choices people have about moving, however, the less likely it is that the outcomes of that movement will be positive. Involuntary resettlement should be a last resort. Many of the most dire risks arising from climate-motivated migration can be avoided through careful policy. Policy responses to minimize the risks associated with migration in response to climate change, and to maximize migration’s contribution to adaptive capacity include: ensuring that migrants have the same rights and opportunities as host communities; reducing the costs of moving money and people between areas of origin and destination; facilitating mutual understanding among migrants and host communities; clarifying property rights where they are contested; ensuring that efforts to assist migrants include host communities; and strengthening regional and international emergency response systems.Population Policies,Climate Change Mitigation and Green House Gases,Health Monitoring&Evaluation,Climate Change Economics,Voluntary and Involuntary Resettlement

Why forums? An empirical analysis into the facilitating factors of carding forums

Over the last decade, the nature of cybercrime has transformed from naive vandalism to profit-driven, leading to the emergence of a global underground economy. A noticeable trend which has surfaced in this economy is the repeated use of forums to operate online stolen data markets. Using interaction data from three prominent carding forums: Shadowcrew, Cardersmarket and Darkmarket, this study sets out to understand why forums are repeatedly chosen to operate online stolen data markets despite numerous successful infiltrations by law enforcement in the past. Drawing on theories from criminology, social psychology, economics and network science, this study has identified four fundamental socio-economic mechanisms offered by carding forums: (1) formal control and coordination; (2) social networking; (3) identity uncertainty mitigation; (4) quality uncertainty mitigation. Together, they give rise to a sophisticated underground market regulatory system that facilitates underground trading over the Internet and thus drives the expansion of the underground economy

Evaluation of power generation operations in response to changes in surface water reservoir storage

We used a customized, river basin-based model of surface water rights to evaluate the response of power plants to drought via simulated changes in reservoir storage. Our methodology models surface water rights in 11 river basins in Texas using five cases: (1) storage decrease of existing capacity of 10%, (2) storage decrease of 50%, (3) complete elimination of storage, (4) storage increase of 10% (all at existing locations), and (5) construction of new reservoirs (at new locations) with a total increase in baseline reservoir capacity for power plant cooling of 9%. Using the Brazos River basin as a sample, we evaluated power generation operations in terms of reliability, resiliency, and vulnerability. As simulated water storage decreases, reliability generally decreases and resiliency and vulnerability remain relatively constant. All three metrics remain relatively constant with increasing reservoir storage, with the exception of one power plant. As reservoir storage changes at power plants, other water users in the basin are also affected. In general, decreasing water storage is beneficial to other water users in the basin, and increasing storage is detrimental for many other users. Our analysis reveals basin-wide and individual power plant-level impacts of changing reservoir storage, demonstrating a methodology for evaluation of the sustainability and feasibility of constructing new reservoir storage as a water and energy management approach.Mechanical Engineerin

Microeconomic foundations of geographical variations in labour productivity

This paper initially presents an exploratory spatial data analysis which indicates the presence of small-scale geographical variations in levels and standard deviations of labour productivity across England and Wales in 2005. We identify the presence of spatial autocorrelation for both measures. This finding motivates a subsequent review and extension of theories which suggest the possible presence of small-scale geographical patterns of labour productivity.Labour productivity; standard deviation; districts and local authorities; geographical autocorrelation

Winners and Losers: Spatial variations in labour productivity in England and Wales

This paper presents an investigation into the static and dynamic spatial pattern of aggregate labour productivity across England and Wales at the district and unit authority level. This analysis is complemented by plant-level regressions to identify the contribution of industrial sectors to each NUTS1 region’s average labour productivity. Using data for 1998 and 2005, our exploratory data analysis illustrates that there are stable spatial patterns in levels of labour productivity and that labour productivity change does not appear to be spatially dependent, at least not at this spatial scale. Furthermore the economic importance of different sectors to different regions evolves over time, which makes regional industrial policy formation problematic.Labour productivity; districts and local authorities; sectors; spatial autocorrelation

Ultrasonic propagation in liquid alloy systems

Imperial Users onl

Job Loss and Effects on Firms and Workers

This paper serves as an introduction and (incomplete) survey of the wide-ranging literature on job loss. We begin with a discussion of job stability in the US and the commitment between firms and workers, and how this has changed in recent years. We then focus on the short and long-term consequences to workers (i.e. wages, health outcomes) following a layoff, and the effect which mass layoffs have on future firm performance. The changing nature of these relationships over the past several decades is a central theme of this paper. We review the common data sources used to examine these questions, and identify many influential papers on each topic. Additionally, we discuss alternative policies to the typical mass layoff, such as worksharing

Can switching fuels save water? A life cycle quantification of freshwater consumption for Texas coal-and natural gas-fired electricity

Thermal electricity generation is a major consumer of freshwater for cooling, fuel extraction and air emissions controls, but the life cycle water impacts of different fossil fuel cycles are not well understood. Much of the existing literature relies on decades-old estimates for water intensity, particularly regarding water consumed for fuel extraction. This work uses contemporary data from specific resource basins and power plants in Texas to evaluate water intensity at three major stages of coal and natural gas fuel cycles: fuel extraction, power plant cooling and power plant emissions controls. In particular, the water intensity of fuel extraction is quantified for Texas lignite, conventional natural gas and 11 unconventional natural gas basins in Texas, including major second-order impacts associated with multi-stage hydraulic fracturing. Despite the rise of this water-intensive natural gas extraction method, natural gas extraction appears to consume less freshwater than coal per unit of energy extracted in Texas because of the high water intensity of Texas lignite extraction. This work uses new resource basin and power plant level water intensity data to estimate the potential effects of coal to natural gas fuel switching in Texas’ power sector, a shift under consideration due to potential environmental benefits and very low natural gas prices. Replacing Texas’ coal-fired power plants with natural gas combined cycle plants (NGCCs) would reduce annual freshwater consumption in the state by an estimated 53 billion gallons per year, or 60% of Texas coal power’s water footprint, largely due to the higher efficiency of NGCCs.Mechanical Engineerin

Infrared Renormalons and Power Suppressed Effects in e+e−e^+e^- Jet Events

We study the effect of infrared renormalons upon shape variables that are commonly used to determine the strong coupling constant in $e^+e^-$ annihilation into hadronic jets. We consider the model of QCD in the limit of large $n_f$. We find a wide variety of different behaviours of shape variables with respect to power suppressed effects induced by infrared renormalons. In particular, we find that oblateness is affected by $1/Q$ non--perturbative effects even away from the two jet region, and the energy--energy correlation is affected by $1/Q$ non--perturbative effects for all values of the angle. On the contrary, variables like thrust, the $c$ parameter, the heavy jet mass, and others, do not develop any $1/Q$ correction away from the two jet region at the leading $n_f$ level. We argue that $1/Q$ corrections will eventually arise at subleading $n_f$ level, but that they could maintain an extra \as(Q) suppression. We conjecture therefore that the leading power correction to shape variables will have in general the form $\alpha^n_{\rm S}(Q)/Q$, and it may therefore be possible to classify shape variables according to the value of $n$.Comment: 20 pages, Latex, epsfig, 3 tar-gzip-uuencoded figures. Also available from http://surya11.cern.ch/users/nason/misc

Rayleigh-Gauss-Newton optimization with enhanced sampling for variational Monte Carlo

Variational Monte Carlo (VMC) is an approach for computing ground-state wavefunctions that has recently become more powerful due to the introduction of neural network-based wavefunction parametrizations. However, efficiently training neural wavefunctions to converge to an energy minimum remains a difficult problem. In this work, we analyze optimization and sampling methods used in VMC and introduce alterations to improve their performance. First, based on theoretical convergence analysis in a noiseless setting, we motivate a new optimizer that we call the Rayleigh-Gauss-Newton method, which can improve upon gradient descent and natural gradient descent to achieve superlinear convergence with little added computational cost. Second, in order to realize this favorable comparison in the presence of stochastic noise, we analyze the effect of sampling error on VMC parameter updates and experimentally demonstrate that it can be reduced by the parallel tempering method. In particular, we demonstrate that RGN can be made robust to energy spikes that occur when new regions of configuration space become available to the sampler over the course of optimization. Finally, putting theory into practice, we apply our enhanced optimization and sampling methods to the transverse-field Ising and XXZ models on large lattices, yielding ground-state energy estimates with remarkably high accuracy after just 200-500 parameter updates.Comment: 12 pages, 7 figure