Large-Scale Modelling of the Divergent Spectrin Repeats in Nesprins: Giant Modular Proteins

Global change and GHG emission modelling are dependent on accurate wetness estimations for predictions of e.g. methane emissions. This study aims to quantify how the slope, drainage area and the TWI vary with the resolution of DEMs for a flat peatland area. Six DEMs with spatial resolutions from 0.5 to 90 m were interpolated with four different search radiuses. The relationship between accuracy of the DEM and the slope was tested. The LiDAR elevation data was divided into two data sets. The number of data points facilitated an evaluation dataset with data points not more than 10 mm away from the cell centre points in the interpolation dataset. The DEM was evaluated using a quantile-quantile test and the normalized median absolute deviation. It showed independence of the resolution when using the same search radius. The accuracy of the estimated elevation for different slopes was tested using the 0.5 meter DEM and it showed a higher deviation from evaluation data for steep areas. The slope estimations between resolutions showed differences with values that exceeded 50%. Drainage areas were tested for three resolutions, with coinciding evaluation points. The model ability to generate drainage area at each resolution was tested by pair wise comparison of three data subsets and showed differences of more than 50% in 25% of the evaluated points. The results show that consideration of DEM resolution is a necessity for the use of slope, drainage area and TWI data in large scale modelling.

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Biotic stress accelerates formation of climate-relevant aerosols in boreal forests

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-12139-2015 ◽

2015 ◽

Vol 15 (21) ◽

pp. 12139-12157 ◽

Cited By ~ 25

Author(s):

J. Joutsensaari ◽

P. Yli-Pirilä ◽

H. Korhonen ◽

A. Arola ◽

J. D. Blande ◽

...

Keyword(s):

Boreal Forests ◽

Large Scale ◽

Transport Model ◽

Cloud Condensation Nuclei ◽

Fold Increase ◽

Global Scale ◽

Satellite Observations ◽

Insect Outbreaks ◽

Voc Emissions ◽

Scale Modelling

Abstract. Boreal forests are a major source of climate-relevant biogenic secondary organic aerosols (SOAs) and will be greatly influenced by increasing temperature. Global warming is predicted to not only increase emissions of reactive biogenic volatile organic compounds (BVOCs) from vegetation directly but also induce large-scale insect outbreaks, which significantly increase emissions of reactive BVOCs. Thus, climate change factors could substantially accelerate the formation of biogenic SOAs in the troposphere. In this study, we have combined results from field and laboratory experiments, satellite observations and global-scale modelling in order to evaluate the effects of insect herbivory and large-scale outbreaks on SOA formation and the Earth's climate. Field measurements demonstrated 11-fold and 20-fold increases in monoterpene and sesquiterpene emissions respectively from damaged trees during a pine sawfly (Neodiprion sertifer) outbreak in eastern Finland. Laboratory chamber experiments showed that feeding by pine weevils (Hylobius abietis) increased VOC emissions from Scots pine and Norway spruce seedlings by 10–50 fold, resulting in 200–1000-fold increases in SOA masses formed via ozonolysis. The influence of insect damage on aerosol concentrations in boreal forests was studied with a global chemical transport model GLOMAP and MODIS satellite observations. Global-scale modelling was performed using a 10-fold increase in monoterpene emission rates and assuming 10 % of the boreal forest area was experiencing outbreak. Results showed a clear increase in total particulate mass (local max. 480 %) and cloud condensation nuclei concentrations (45 %). Satellite observations indicated a 2-fold increase in aerosol optical depth over western Canada's pine forests in August during a bark beetle outbreak. These results suggest that more frequent insect outbreaks in a warming climate could result in substantial increase in biogenic SOA formation in the boreal zone and, thus, affect both aerosol direct and indirect forcing of climate at regional scales. The effect of insect outbreaks on VOC emissions and SOA formation should be considered in future climate predictions.

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Modelling the attraction of travel to shopping destinations in large-scale modelling

Transport Policy ◽

10.1016/j.tranpol.2018.04.013 ◽

2018 ◽

Vol 68 ◽

pp. 52-62 ◽

Cited By ~ 5

Author(s):

Ida Kristoffersson ◽

Andrew Daly ◽

Staffan Algers

Keyword(s):

Large Scale ◽

Scale Modelling

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Aspects of Large Scale Modelling

Energy and Water Cycles in the Climate System ◽

10.1007/978-3-642-76957-3_2 ◽

1993 ◽

pp. 43-67

Author(s):

Ernst Klinker

Keyword(s):

Large Scale ◽

Scale Modelling

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Challenges in modelling isoprene and monoterpene emission dynamics of Arctic plants: a case study from a subarctic tundra heath

Biogeosciences ◽

10.5194/bg-13-6651-2016 ◽

2016 ◽

Vol 13 (24) ◽

pp. 6651-6667 ◽

Cited By ~ 9

Author(s):

Jing Tang ◽

Guy Schurgers ◽

Hanna Valolahti ◽

Patrick Faubert ◽

Päivi Tiiva ◽

...

Keyword(s):

Response Curve ◽

Large Scale ◽

Ecosystem Model ◽

The Arctic ◽

Short Term ◽

Response Curves ◽

Arctic Plants ◽

Scale Modelling

Abstract. The Arctic is warming at twice the global average speed, and the warming-induced increases in biogenic volatile organic compounds (BVOCs) emissions from Arctic plants are expected to be drastic. The current global models' estimations of minimal BVOC emissions from the Arctic are based on very few observations and have been challenged increasingly by field data. This study applied a dynamic ecosystem model, LPJ-GUESS, as a platform to investigate short-term and long-term BVOC emission responses to Arctic climate warming. Field observations in a subarctic tundra heath with long-term (13-year) warming treatments were extensively used for parameterizing and evaluating BVOC-related processes (photosynthesis, emission responses to temperature and vegetation composition). We propose an adjusted temperature (T) response curve for Arctic plants with much stronger T sensitivity than the commonly used algorithms for large-scale modelling. The simulated emission responses to 2 °C warming between the adjusted and original T response curves were evaluated against the observed warming responses (WRs) at short-term scales. Moreover, the model responses to warming by 4 and 8 °C were also investigated as a sensitivity test. The model showed reasonable agreement to the observed vegetation CO2 fluxes in the main growing season as well as day-to-day variability of isoprene and monoterpene emissions. The observed relatively high WRs were better captured by the adjusted T response curve than by the common one. During 1999–2012, the modelled annual mean isoprene and monoterpene emissions were 20 and 8 mg C m−2 yr−1, with an increase by 55 and 57 % for 2 °C summertime warming, respectively. Warming by 4 and 8 °C for the same period further elevated isoprene emission for all years, but the impacts on monoterpene emissions levelled off during the last few years. At hour-day scale, the WRs seem to be strongly impacted by canopy air T, while at the day–year scale, the WRs are a combined effect of plant functional type (PFT) dynamics and instantaneous BVOC responses to warming. The identified challenges in estimating Arctic BVOC emissions are (1) correct leaf T estimation, (2) PFT parameterization accounting for plant emission features as well as physiological responses to warming, and (3) representation of long-term vegetation changes in the past and the future.

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A fully distributed unstructured Navier-Stokes solver for large-scale aeroelasticity computations

The Aeronautical Journal ◽

10.1017/s0001924000012392 ◽

2001 ◽

Vol 105 (1050) ◽

pp. 419-426 ◽

Cited By ~ 10

Author(s):

G. Barakos ◽

M. Vahdati ◽

A.I. Sayma ◽

C. Bréard ◽

M. Imregun

Keyword(s):

Large Scale ◽

Numerical Models ◽

Navier Stokes ◽

Multiple Data ◽

Computational Mesh ◽

Blade Row ◽

Scale Modelling ◽

Modelling Methodology ◽

Speed Up ◽

Development And Validation

Abstract This paper presents the development and validation of a parallel unsteady flow and aeroelasticity code for large-scale numerical models used in turbo machinery applications. The work is based on an existing unstructured Navier-Stokes solver developed over the past ten years by the Aeroelasticity Research Group at Imperial College Vibration University Technology Centre. The single-process multiple-data paradigm was adopted for the parallelisation of the solver and several validation cases were considered. The computational mesh was divided into several sub-sections using a domain decomposition technique. The performance and numerical accuracy of the parallel solver was validated across several computer platforms for various problem sizes. In cases where the solution could be obtained on a single CPU, the serial and parallel versions of the code were found to produce identical results. Studies on up to 32 CPUs showed varying levels of parallelisation efficiency, an almost linear speed-up being obtained in some cases. Finally, an industrial configuration, a 17 blade row turbine with a 47 million point mesh, was discussed to illustrate the potential of the proposed large-scale modelling methodology.

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Induction Heat Treatment for an Automotive Crankshaft: Large Scale Modelling with Moving Inductors

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.554-557.1539 ◽

2013 ◽

Vol 554-557 ◽

pp. 1539-1544

Author(s):

Steffen Klonk ◽

Francois Bay

Keyword(s):

Heat Treatment ◽

Numerical Model ◽

Large Scale ◽

Moving Boundaries ◽

Discrete Level ◽

Mesh Quality ◽

Induction Heat ◽

Induction Heat Treatment ◽

Subsequent Time ◽

Scale Modelling

A numerical model for a multiphysics problem is presented. It includes the movement of subdomains, which are embedded in a global air domain. The description of the movement is based on a discrete level set representation of the moving boundaries. It is based on the original geometry of the moving tools, such that the mesh quality is not reduced in subsequent time steps.

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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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HydroSOS: a pilot global Hydrological Status and Outlook System integrating national to global scale hydrological services for increased resilience to hydro-climatic risks

10.5194/egusphere-egu2020-7554 ◽

2020 ◽

Author(s):

Katie Smith ◽

Luis Roberto Silva Vara ◽

Harry Dixon ◽

Victoria Barlow ◽

Alan Jenkins ◽

...

Keyword(s):

Large Scale ◽

Lake Victoria ◽

Pilot Project ◽

Global Scale ◽

Lake Victoria Basin ◽

Scale Modelling ◽

Technical Specifications ◽

Climatic Risks ◽

Main Activity ◽

Hydrological Services

Consistent hydrological status and outlook information across transboundary basins or regions of shared hydrological interest are not often available. Furthermore, whilst large-scale modelling capabilities are continually improving, there is an information and confidence gap between locally informed hydrological status information products and those developed globally.HydroSOS is World Meteorological Organisation initiative that aims to increase global resilience to hydro-climatic risks through the production of hydrological status and outlooks assessments at different scales around the world. Currently in a pilot phase, HydroSOS is being developed through a collaboration between National Hydrometeorological Services, transboundary basin organisations, global modelling centres and the research community. The system will provide an appraisal of where current hydrological status is different from &#8220;normal&#8221;, as well as sub-seasonal to seasonal outlooks indicating whether this is likely to get better or worse over the coming weeks and months.The HydroSOS programme consists of five main activity streams:<ol><li>Increasing the interoperability of hydrological status and outlook products through Common Technical Specifications.</li> <li>Increasing national capabilities to generate hydrological status and sub-seasonal to seasonal outlook products through Guidance on Methods and Tools.</li> <li>Increasing the utility of large-scale hydrological status and outlook modelling through Co-design of Global Products, with international partners working from local to global scale.</li> <li>Increasing shared production of transboundary hydrological status and outlook products through Regional Pilots, initially in South Asia and the Lake Victoria Basin.</li> <li>Integration of hydrological status and outlook products for national, regional and global users through a Demonstration Portal.</li> </ol>This PICO contribution will present progress in the pilot project to date, including a hands-on demonstration of the web portal.

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