Small scale modelling of brickwork arch bridges using a centrifuge

AbstractThe shallow, gently sloping, sandy-silty seabed of the Venetian coast (Italy) is studded by a number of outcropping rocky systems of different size encouraging the development of peculiar zoobenthic biocenoses with considerably higher biodiversity indexes compared to neighbouring areas. In order to protect and enhance the growth of settling communities, artificial monolithic reefs were deployed close to the most important formations, providing further nesting sites and mechanical hindrance to illegal trawl fishing.In this framework, a multi-step and multi-scale numerical modelling activity was carried out to predict the perturbations induced by the presence of artificial structures on sediment transport over the outcroppings and their implications on turbidity and water quality. After having characterized wave and current circulation climate at the sub-basin scale over a reference year, a set of small scale simulations was carried out to describe the effects of a single monolith under different geometries and hydrodynamic forcings, encompassing the conditions likely occurring at the study sites. A dedicated tool was then developed to compose the information contained in the small-scale database into realistic deployment configurations, and applied in four protected outcroppings identified as test sites. With reference to these cases, under current meteomarine climate the application highlighted a small and localised increase in suspended sediment concentration, suggesting that the implemented deployment strategy is not likely to produce harmful effects on turbidity close to the outcroppings.In a broader context, the activity is oriented at the tuning of a flexible instrument for supporting the decision-making process in benthic environments of outstanding environmental relevance, especially in the Integrated Coastal Zone Management or Maritime Spatial Planning applications. The dissemination of sub-basin scale modelling results via the THREDDS Data Server, together with an user-friendly software for composing single-monolith runs and a graphical interface for exploring the available data, significantly improves the quantitative information collection and sharing among scientists, stakeholders and policy-makers.

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EMPOL 1.0: a new parameterization of pollen emission in numerical weather prediction models

Geoscientific Model Development ◽

10.5194/gmd-6-1961-2013 ◽

2013 ◽

Vol 6 (6) ◽

pp. 1961-1975 ◽

Cited By ~ 26

Author(s):

K. Zink ◽

A. Pauling ◽

M. W. Rotach ◽

H. Vogel ◽

P. Kaufmann ◽

...

Keyword(s):

Numerical Weather Prediction ◽

Prediction Models ◽

Weather Prediction ◽

Birch Pollen ◽

Small Scale ◽

Pollen Emission ◽

Numerical Weather ◽

Pollen Concentrations ◽

Scale Modelling ◽

Reactive Trace Gases

Abstract. Simulating pollen concentrations with numerical weather prediction (NWP) systems requires a parameterization for pollen emission. We have developed a parameterization that is adaptable for different plant species. Both biological and physical processes of pollen emission are taken into account by parameterizing emission as a two-step process: (1) the release of the pollen from the flowers, and (2) their entrainment into the atmosphere. Key factors influencing emission are temperature, relative humidity, the turbulent kinetic energy and precipitation. We have simulated the birch pollen season of 2012 using the NWP system COSMO-ART (Consortium for Small-scale Modelling – Aerosols and Reactive Trace Gases), both with a parameterization already present in the model and with our new parameterization EMPOL. The statistical results show that the performance of the model can be enhanced by using EMPOL.

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Implementation of an Urban Parameterization Scheme into the Regional Climate Model COSMO-CLM

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-12-0209.1 ◽

2013 ◽

Vol 52 (10) ◽

pp. 2296-2311 ◽

Cited By ~ 28

Author(s):

Kristina Trusilova ◽

Barbara Früh ◽

Susanne Brienen ◽

Andreas Walter ◽

Valéry Masson ◽

...

Keyword(s):

Spatial Resolution ◽

Climate Model ◽

Spatial Scales ◽

Regional Climate ◽

Coupled Model ◽

Urban Land ◽

Urban Land Use ◽

Small Scale ◽

Model Simulations ◽

Scale Modelling

AbstractAs the nonhydrostatic regional model of the Consortium for Small-Scale Modelling in Climate Mode (COSMO-CLM) is increasingly employed for studying the effects of urbanization on the environment, the authors extend its surface-layer parameterization by the Town Energy Budget (TEB) parameterization using the “tile approach” for a single urban class. The new implementation COSMO-CLM+TEB is used for a 1-yr reanalysis-driven simulation over Europe at a spatial resolution of 0.11° (~12 km) and over the area of Berlin at a spatial resolution of 0.025° (~2.8 km) for evaluating the new coupled model. The results on the coarse spatial resolution of 0.11° show that the standard and the new models provide 2-m temperature and daily precipitation fields that differ only slightly by from −0.1 to +0.2 K per season and ±0.1 mm day−1, respectively, with very similar statistical distributions. This indicates only a negligibly small effect of the urban parameterization on the model's climatology. Therefore, it is suggested that an urban parameterization may be omitted in model simulations on this scale. On the spatial resolution of 0.025° the model COSMO-CLM+TEB is able to better represent the magnitude of the urban heat island in Berlin than the standard model COSMO-CLM. This finding shows the importance of using the parameterization for urban land in the model simulations on fine spatial scales. It is also suggested that models could benefit from resolving multiple urban land use classes to better simulate the spatial variability of urban temperatures for large metropolitan areas on spatial scales below ~3 km.

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Stochastic Small-Scale Modelling of Turbulent Wind Time Series

Wind Energy ◽

10.1007/978-3-540-33866-6_22 ◽

2007 ◽

pp. 123-127

Author(s):

Jochen Cleve ◽

Martin Greiner

Keyword(s):

Time Series ◽

Small Scale ◽

Turbulent Wind ◽

Scale Modelling

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The physical impact of towed demersal fishing gears on soft sediments

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv125 ◽

2015 ◽

Vol 73 (suppl_1) ◽

pp. i5-i14 ◽

Cited By ~ 30

Author(s):

F. G. O'Neill ◽

A. Ivanović

Keyword(s):

Mathematical Modelling ◽

Large Scale ◽

Lateral Displacement ◽

Field Measurements ◽

Small Scale ◽

Physical Interaction ◽

Soft Sediments ◽

Fishing Gears ◽

Scale Modelling ◽

Physical Impact

Abstract An improved understanding of the physical interaction of towed demersal fishing gears with the seabed has been developed in recent years, and there is a clearer view of the underpinning mechanical processes that lead to the modification and alteration of the benthic environment. The physical impact of these gears on soft sediments can be classified broadly as being either geotechnical or hydrodynamic in nature: penetration and piercing of the substrate, lateral displacement of sediment, and the influence of the pressure field transmitted through the sediment can be considered geotechnical, whereas the mobilization of sediment into the water column can be considered hydrodynamic. A number of experimental and numerical approaches have been used to gain better insights of these physical processes. These include small-scale modelling in towing tanks and sand channels; large-scale modelling in the field; measurements behind full-scale towed gears at sea; numerical/mathematical modelling of sediment mechanics; and numerical/mathematical modelling of hydrodynamics. Here, we will review this research, and that in associated fields, and show how it can form the basis of predictive models of the benthic impact of trawl gears.

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Cosmological constraints from galaxy–lensing cross-correlations using BOSS galaxies with SDSS and CMB lensing

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2922 ◽

2019 ◽

Vol 491 (1) ◽

pp. 51-68 ◽

Cited By ~ 3

Author(s):

Sukhdeep Singh ◽

Rachel Mandelbaum ◽

Uroš Seljak ◽

Sergio Rodríguez-Torres ◽

Anže Slosar

Keyword(s):

Cosmological Parameters ◽

Small Scale ◽

The Galaxy ◽

Scale Modelling ◽

Modelling Uncertainties ◽

Cent Level ◽

Cross Correlations ◽

Galaxy Bias ◽

The Impact ◽

Parameter Constraints

ABSTRACT We present cosmological parameter constraints based on a joint modelling of galaxy–lensing cross-correlations and galaxy clustering measurements in the SDSS, marginalizing over small-scale modelling uncertainties using mock galaxy catalogues, without explicit modelling of galaxy bias. We show that our modelling method is robust to the impact of different choices for how galaxies occupy dark matter haloes and to the impact of baryonic physics (at the $\sim 2{{\ \rm per\ cent}}$ level in cosmological parameters) and test for the impact of covariance on the likelihood analysis and of the survey window function on the theory computations. Applying our results to the measurements using galaxy samples from BOSS and lensing measurements using shear from SDSS galaxies and CMB lensing from Planck, with conservative scale cuts, we obtain $S_8\equiv \left(\frac{\sigma _8}{0.8228}\right)^{0.8}\left(\frac{\Omega _\mathrm{ m}}{0.307}\right)^{0.6}=0.85\pm 0.05$ (stat.) using LOWZ × SDSS galaxy lensing, and S8 = 0.91 ± 0.1 (stat.) using combination of LOWZ and CMASS × Planck CMB lensing. We estimate the systematic uncertainty in the galaxy–galaxy lensing measurements to be $\sim 6{{\ \rm per\ cent}}$ (dominated by photometric redshift uncertainties) and in the galaxy–CMB lensing measurements to be $\sim 3{{\ \rm per\ cent}}$, from small-scale modelling uncertainties including baryonic physics.

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Modelling a Snowdrift by Means of Activated Clay Particles

Annals of Glaciology ◽

10.3189/1985aog6-1-48-52 ◽

1985 ◽

Vol 6 ◽

pp. 48-52 ◽

Cited By ~ 1

Author(s):

Yutaka Anno

Keyword(s):

Angle Of Repose ◽

Scale Model ◽

Small Scale ◽

High Angle ◽

Clay Particles ◽

Wide Range ◽

Wet Snow ◽

Scale Modelling ◽

Natural Snow ◽

Small Scale Model

This paper presents a small scale modelling of a snowdrift using activated clay particles.Characteristic properties of activated clay particles, which are different from model snow particles proposed previously by other investigators, are fineness, high angle of repose and wide range of cohesion. Such properties may provide a similitude of a snowdrift and the phenomena caused by wet snow particles in a small scale model.Experimental results presented in this paper show that activated clay particles are the most suitable substitute for natural snow particles in modelling, and indicate also the possibility of using them to model wet snow particles.

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Spatial Postprocessing of Ensemble Forecasts for Temperature Using Nonhomogeneous Gaussian Regression

Monthly Weather Review ◽

10.1175/mwr-d-14-00210.1 ◽

2015 ◽

Vol 143 (3) ◽

pp. 955-971 ◽

Cited By ~ 41

Author(s):

Kira Feldmann ◽

Michael Scheuerer ◽

Thordis L. Thorarinsdottir

Keyword(s):

Bayesian Model Averaging ◽

Forecast Error ◽

Gaussian Random Field ◽

Rank Correlation ◽

Model Averaging ◽

Small Scale ◽

Ensemble Forecasts ◽

Weather Forecasts ◽

Scale Modelling ◽

Gaussian Regression

Abstract Statistical postprocessing techniques are commonly used to improve the skill of ensembles from numerical weather forecasts. This paper considers spatial extensions of the well-established nonhomogeneous Gaussian regression (NGR) postprocessing technique for surface temperature and a recent modification thereof in which the local climatology is included in the regression model to permit locally adaptive postprocessing. In a comparative study employing 21-h forecasts from the Consortium for Small Scale Modelling ensemble predictive system over Germany (COSMO-DE), two approaches for modeling spatial forecast error correlations are considered: a parametric Gaussian random field model and the ensemble copula coupling (ECC) approach, which utilizes the spatial rank correlation structure of the raw ensemble. Additionally, the NGR methods are compared to both univariate and spatial versions of the ensemble Bayesian model averaging (BMA) postprocessing technique.

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Towards opensource LOD2 modelling of urban spaces using an optimised machine learning and rules-based approach.

10.5194/egusphere-egu2020-21911 ◽

2020 ◽

Author(s):

Tom Rowan ◽

Adrian Butler

Keyword(s):

Water Management ◽

Machine Learning ◽

Water Conservation ◽

Three Dimensional ◽

Flood Management ◽

Local Scale ◽

Small Scale ◽

Test Case ◽

Local Planning ◽

Scale Modelling

In order to enable community groups and other interested parties to evaluate the effects of flood management, water conservation and other hydrological issues, better localised mapping is required.&#160; Although some maps are publicly available many are behind paywalls, especially those with three dimensional features. &#160;In this study London is used as a test case to evaluate, machine learning and rules-based approaches with opensource maps and LiDAR data to create more accurate representations (LOD2) of small-scale areas. &#160;Machine learning is particularly well suited to the recognition of local repetitive features like building roofs and trees, while roads can be identified and mapped best using a faster rules-based approach. In order to create a useful LOD2 representation, a user interface, processing rules manipulation and assumption editor have all been incorporated. Features like randomly assigning sub terrain features (basements) - using Monte-Carlo methods - and artificial sewage representation enable the user to grow these models from opensource data into useful model inputs. This project is aimed at local scale hydrological modelling, rainfall runoff analysis and other local planning applications. &#160;The goal is to provide turn-key data processing for small scale modelling, which should help advance the installation of SuDs and other water management solutions, as well as having broader uses. The method is designed to enable fast and accurate representations of small-scale features (1 hectare to 1km2), with larger scale applications planned for future work. &#160;This work forms part of the CAMELLIA project (Community Water Management for a Liveable London) and aims to provide useful tools for local scale modeller and possibly the larger scale industry/scientific user.

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