FISHRENT; Bio-economic simulation and optimisation model

Key findings: The FISHRENT model is a major step forward in bio-economic model-ling, combining features that have not been fully integrated in earlier models: 1- Incorporation of any number of species (or stock) and/or fleets 2- Integration of simulation and optimisation over a period of 25 years 3- Integration of effort and TAC-driven management policies 4- Three independent relations for stock growth, production and investments. The feedbacks within the model allow for a dynamic simulation. The main application of the model is scenario analysis of policy options. Complementary findings: The model formulates a complete set of mathematical relations, but it also con-tains a number of important assumptions, which remain to be tested empirically. Therefore the model presents a challenging agenda for empirical research, which should lead to further qualitative and quantitative improvements of the in-dividual mathematical equations and parameter values. Method: This model was developed during the EU-funded project 'Remuneration of spawning stock biomass'. Its aim was to generate consistent sets of scenarios for an assessment of potential resource rents in different EU fisheries. The model comprises six modules, each focussing on a different aspect of the functioning of the fisheries system: biology (stocks), economy (costs, earnings and profits), policy (TACs, effort and access fees), behaviour (investments), prices (fish and fuel) and an interface linking the modules together. Input, calculation and output are clearly separated. The model produces a standard set of graphics, which provide a quick insight into the results of any model run. All output of the model runs can be exported to database software for further analysis. The model has been built in Excel, which makes it accessible for most us-ers. It has been used in new applications and even translated to other software. The model is continually further developed

Unsatisfying forecast of a Mediterranean cyclone: a verification study employing state-of-the-art techniques

International audienceOn 16?17 November 2000, a relatively intense precipitation event on the north-western Italy was heavily underestimated, mainly due to shifting error, by three operational 10-km limited area models (LAMs) which differ about basic equations, domain size, and parameterisation schemes. The scope of the work is to investigate possible common error-sources independent from the single model, in particular the effect of initialisation. Thus, the complex evolution over the western Mediterranean Sea of the cyclone responsible for the event was investigated. Several objective and subjective verification techniques have been employed to check one of the LAMs' forecast against the available observations (precipitation from rain gauge and retrieved from ground-based radar, and satellite-retrieved atmospheric humidity patterns). Despite a clear statement is not achieved, results indicate that high sensitivity to the initial conditions, and the inadequacy of the observational network on the southern Mediterranean area, can play a major role in producing the forecast shifting error on the target area

On the economic nature of consumers\u2019 willingness to pay for a selective and sustainable fishery: A comparative empirical study

Special issue on Discards regulation vs Mediterranean fisheries sustainability.-- 6 pages, 2 tables[EN] The EU Landing Obligation (LO) bans discards to incentivize a more selective and sustainable fishery. This regulation may induce a cost to the fishing industry that could be transferred to final fish consumers. We aim to assess the consumers’ reservation price for a sustainable and selective fishery. The methodology follows two steps: We first assess the value of the reservation price (willingness to pay, WTP) for a sustainable and selective fishery by using contingent valuation methods from a comparative perspective in Spain and Italy. We then attempt to empirically assess the components of WTP by using an original model specification that, unlike those presented in the literature, exogenizes socio-economic variables and uses ideological indicators to explain WTP in a two-line simultaneous model estimated by instrumental variable regression. The results show a positive, though low, WTP across the two samples, and very different impacts of estimated coefficients on the WTP for the two samples. A preliminary interpretation of this divergence highlights that Italian consumers consider LO-incentivized sustainable fishery a pure public good linked to issues of legality, and Spanish consumers consider it an impure public good linked to environmental issues. These differences may indicate how strongly the institutions and the policies in each region are perceived by a different human capital structure. They may also indicate that the problem, the perceptions of it and the solutions to it differ according to the context[ES] La obligación de desembarque de la Unión Europea (LO) prohíbe los descartes para incentivar una pesquería más selectiva y sostenible. Esta regulación puede inducir costes a la industria pesquera que a su vez pueden ser transferidos al consumidor final. Nuestro objetivo es evaluar el precio de reserva del consumidor para una pesquería más sostenible y selectiva. La metodología se basa en dos fases: primero, evaluamos el precio de reserva (disposición a pagar, WTP) para una pesquería sostenible y selectiva mediante métodos de valoración contingente (CV) en un estudio comparativo entre España e Italia. En una segunda fase intentamos estimar empíricamente los componentes de esta WTP mediante la especificación original de un modelo que, a diferencia de la literatura existente, exogeniza las variables socioeconómicas y usa indicadores ideológicos para explicar la WTP, en una regresión bi-funcional con variables instrumentales (IV). Los resultados muestran una WTP positiva, aunque reducida, en ambas muestras, y permiten deducir un impacto distinto de los coeficientes estimados en la WTP. La interpretación preliminar de esta divergencia hace destacar que los consumidores italianos consideran como un bien público puro a una pesquería sostenible incentivada mediante LO, relacionado con aspectos de legalidad, mientras que los consumidores españoles consideran ese modelo de pesquería como un bien público impuro, relacionado con conservación ambiental. Estas diferencias pueden indicar la fortaleza con la que dos estructuras distintas de capital humano perciben las instituciones y las políticas de cada región. También sugieren una distinta percepción, existencia y solución del problema en un contexto distintoThis research was funded by EU H2020 Research and Innovation Action “MINOUW” (contract nº 634495)Peer reviewe

A multiscale approach for precipitation verification applied to the FORALPS case studies

International audienceMultiscale methods, such as the power spectrum, are suitable diagnostic tools for studying the second order statistics of a gridded field. For instance, in the case of Numerical Weather Prediction models, a drop in the power spectrum for a given scale indicates the inability of the model to reproduce the variance of the phenomenon below the correspondent spatial scale. Hence, these statistics provide an insight into the real resolution of a gridded field and must be accurately known for interpolation and downscaling purposes. In this work, belonging to the EU INTERREG IIIB Alpine Space FORALPS project, the power spectra of the precipitation fields for two intense rain events, which occurred over the north-eastern alpine region, have been studied in detail. A drop in the power spectrum at the shortest scales (about 30 km) has been found, as well as a strong matching between the precipitation spectrum and the spectrum of the orography. Furthermore, it has also been shown how the spectra help understand the behavior of the skill scores traditionally used in Quantitative Precipitation Forecast verification, as these are sensitive to the amount of small scale detail present in the fields

Localizing compact binary inspirals on the sky using ground-based gravitational wave interferometers

The inspirals and mergers of compact binaries are among the most promising events for ground-based gravitational-wave (GW) observatories. The detection of electromagnetic (EM) signals from these sources would provide complementary information to the GW signal. It is therefore important to determine the ability of gravitational-wave detectors to localize compact binaries on the sky, so that they can be matched to their EM counterparts. We use Markov Chain Monte Carlo techniques to study sky localization using networks of ground-based interferometers. Using a coherent-network analysis, we find that the Laser Interferometer Gravitational Wave Observatory (LIGO)-Virgo network can localize 50% of their ~8 sigma detected neutron star binaries to better than 50 sq.deg. with 95% confidence region. The addition of the Large Scale Cryogenic Gravitational Wave Telescope (LCGT) and LIGO-Australia improves this to 12 sq.deg.. Using a more conservative coincident detection threshold, we find that 50% of detected neutron star binaries are localized to 13 sq.deg. using the LIGO-Virgo network, and to 3 sq.deg. using the LIGO-Virgo-LCGT-LIGO-Australia network. Our findings suggest that the coordination of GW observatories and EM facilities offers great promise.Comment: 6 pages, 4 figures, 1 table, matches published version in ApJ (incorporates referee's comments

Detection, Localization and Characterization of Gravitational Wave Bursts in a Pulsar Timing Array

Efforts to detect gravitational waves by timing an array of pulsars have focused traditionally on stationary gravitational waves: e.g., stochastic or periodic signals. Gravitational wave bursts --- signals whose duration is much shorter than the observation period --- will also arise in the pulsar timing array waveband. Sources that give rise to detectable bursts include the formation or coalescence of supermassive black holes (SMBHs), the periapsis passage of compact objects in highly elliptic or unbound orbits about a SMBH, or cusps on cosmic strings. Here we describe how pulsar timing array data may be analyzed to detect and characterize these bursts. Our analysis addresses, in a mutually consistent manner, a hierarchy of three questions: \emph{i}) What are the odds that a dataset includes the signal from a gravitational wave burst? \emph{ii}) Assuming the presence of a burst, what is the direction to its source? and \emph{iii}) Assuming the burst propagation direction, what is the burst waveform's time dependence in each of its polarization states? Applying our analysis to synthetic data sets we find that we can \emph{detect} gravitational waves even when the radiation is too weak to either localize the source of infer the waveform, and \emph{detect} and \emph{localize} sources even when the radiation amplitude is too weak to permit the waveform to be determined. While the context of our discussion is gravitational wave detection via pulsar timing arrays, the analysis itself is directly applicable to gravitational wave detection using either ground or space-based detector data.Comment: 43 pages, 13 figures, submitted to ApJ

A Technique for In-situ Measurement of Free Spectral Range and Transverse Mode Spacing of Optical Cavities

Length and g-factor are fundamental parameters that characterize optical cavities. We developed a technique to measure these parameters in-situ by determining the frequency spacing between the resonances of fundamental and spatial modes of an optical cavity. Two laser beams are injected into the cavity, and their relative frequency is scanned by a phase-lock loop, while the cavity is locked to either laser. The measurement of the amplitude of their beat note in transmission reveals the resonances of the longitudinal and the transverse modes of the cavity and their spacing. This method proves particularly useful to characterize complex optical systems, including very long and/or coupled optical cavities, as in gravitational wave interferometers. This technique and the results of its application to the coupled cavities of a 40-meter-long gravitational wave interferometer prototype are here presented

Cryogenic and room temperature strength of sapphire jointed by hydroxide-catalysis bonding

Hydroxide-catalysis bonding is a precision technique used for jointing components in opto-mechanical systems and has been implemented in the construction of quasi-monolithic silica suspensions in gravitational wave detectors. Future detectors are likely to operate at cryogenic temperatures which will lead to a change in test mass and suspension material. One candidate material is mono-crystalline sapphire. Here results are presented showing the influence of various bonding solutions on the strength of the hydroxide-catalysis bonds formed between sapphire samples, measured both at room temperature and at 77 K, and it is demonstrated that sodium silicate solution is the most promising in terms of strength, producing bonds with a mean strength of 63 MPa. In addition the results show that the strengths of bonds were undiminished when tested at cryogenic temperatures