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This article focuses on the science–policy interaction in international negotiations in the context of the United Nations Economic Commission for Europe's Convention for Long Range Transboundary Air Pollution (CLRTAP). It addresses the question how participants in the assessment process divide and co-ordinate work between science and policy and how this enhances credibility, legitimacy and relevance with multiple audiences. For this purpose the article combines an analytical framework to approach effectiveness of scientific assessment in policy making, with the notion of boundary work and co-production of science and policy. The article argues that knowledge produced within the CLRTAP process and the institutional setting in which this knowledge production takes place cannot be separated from each other. Furthermore credibility, legitimacy and relevance are to a large extent determined by boundary work in an early stage of the process. At the same time boundary work has to take place continuously in order keep the assessment process credible, legitimate and relevant for new audiences. The application of a combined framework for analysing credibility, legitimacy and relevance and for analysing boundary work turns out to be helpful in describing in detail what happens in practice at the science–policy interface. In particular it helps to address the question of the way participants in the assessment process divide and co-ordinate work, how this shapes design elements and how this enhances credibility legitimacy and relevance of an assessment. 相似文献
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Edsko E. Havinga Leen W. Horssen Wolter Hoeve Hans Wynberg E. W. Meijer 《Astrophysics and Space Science》2002,282(1):359-359
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Author Index 相似文献3.
Hilde Eggermont Oliver Heiri James Russell Mathias Vuille Leen Audenaert Dirk Verschuren 《Journal of Paleolimnology》2010,43(3):413-435
Fossil assemblages of chironomid larvae (non-biting midges) preserved in lake sediments are well-established paleothermometers
in north-temperate and boreal regions, but their potential for temperature reconstruction in tropical regions has never before
been assessed. In this study, we surveyed sub-fossil chironomid assemblages in the surface sediments of 65 lakes and permanent
pools in southwestern Uganda (including the Rwenzori Mountains) and central and southern Kenya (including Mount Kenya) to
document the modern distribution of African chironomid communities along the regional temperature gradient covered by lakes
situated between 489 and 4,575 m above sea level (a.s.l). We then combined these faunal data with linked Surface-Water Temperature
(SWTemp: range 2.1–28.1°C) and Mean Annual Air Temperature (MATemp: range 1.1–24.9°C) data to develop inference models for
quantitative paleotemperature reconstruction. Here we compare and discuss the performance of models based on different numerical
techniques [weighted-averaging (WA), weighted-averaging partial-least-squares (WA-PLS) and a weighted modern analogue technique
(WMAT)], and on subsets of lakes with varying gradient lengths of temperature and other environmental variables. All inference
models calibrated against MATemp have a high coefficient of determination (
r\textjack2 r_{\text{jack}}^{2} = 0.81–0.97), low maximum bias (0.84–2.59°C), and low root-mean-squared error of prediction (RMSEP = 0.61–1.50°C). The statistical
power of SWTemp models is generally weaker (
r\textjack2 r_{\text{jack}}^{2} = 0.77–0.95; maximum bias 1.55–3.73°C; RMSEP = 1.39–1.98°C), likely because the surface-water temperature data are spot measurements
failing to catch significant daily and seasonal variation. Models based on calibration over the full temperature gradient
suffer slightly from the limited number of study sites at intermediate elevation (2,000–3,000 m), and from the presence of
morphologically indistinguishable but ecologically distinct taxa. Calibration confined to high-elevation sites (>3,000 m)
has poorer error statistics, but is less susceptible to biogeographical and taxonomic complexities. Our results compare favourably
with chironomid-based temperature inferences in temperate regions, indicating that chironomid-based temperature reconstruction
in tropical Africa can be achieved. 相似文献
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During the last decade, several offshore wind-farms were built and offshore wind energy promises to be a suitable alternative to provide green energy. However, there are still some engineering challenges in placing the foundations of offshore wind turbines. For example, wave run-up and wave impacts cause unexpected damage to boat landing facilities and platforms. To assess the forces due to wave run-up, the distribution of run-up around the pile and the maximum run-up height need to be known. This article describes a physical model study of the run-up heights and run-up distribution on two shapes of foundations for offshore wind turbines, including both regular and irregular waves. The influence of wave steepness, wave height and water depth on run-up is investigated. The measured run-up values are compared with applicable theories and previous experimental studies predicting run-up on a circular pile. 相似文献
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Together with new opportunities, offshore wind farms raise new engineering challenges. An important aspect relates to the erosion of bottom material around the foundation of the wind turbines, caused by the local increase of the wave and current induced flow velocities by the pile's presence. Typically, the expected scour has a considerable impact on the stability and dynamic behavior of the wind turbine and a scour protection is placed to avoid erosion of the soil close to the foundation. Although much experience exists on the design of scour protections around bridge piers (which are placed in a current alone situation), at present, little design guidelines exist for the specific case of a scour protection around a monopile foundation subjected to a combined wave and current loading. 相似文献
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Fast data assimilation using a nonlinear Kalman filter and a model surrogate: An application to the Columbia River estuary 总被引：3，自引：0，他引：3
Sergey Frolov Antnio M. Baptista Todd K. Leen Zhegdong Lu Rudolph van der Merwe 《Dynamics of Atmospheres and Oceans》2009,48(1-3):16
A fast and adjoint-free nonlinear data assimilation (DA) system was developed to simulate 3D baroclinic circulation in estuaries, leveraging two recently developed technologies: (1) a nonlinear model surrogate that executes forward simulation three orders of magnitude faster than a forward numerical circulation code and (2) a nonlinear extension to the reduced-dimension Kalman filter that estimates the state of the model surrogate. The noise sources in the Kalman filter were calibrated using empirical cross-validation and accounted for errors in model and model forcing.The DA system was applied to assimilate in situ measurements of water levels, salinities, and temperatures in simulations of the Columbia River estuary. To validate the DA results, we used a combination of cross-validation studies, process-oriented studies, and tests of statistical and dynamical consistency. The validation studies showed that DA improved the representation of several important processes in the estuary, including nonlinear tidal propagation, salinity intrusion, estuarine residual circulation, heat balance, and response of the estuary to coastal winds. 相似文献
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