This document summarizes a study comparing mesoscale models for modeling icing climate. It finds that while the major models (AROME, COAMPS, WRF) capture overall meteorological conditions similarly, they show differences in key variables like temperature near 0°C and hours of active icing. Sensitivity tests show the modeled icing load depends on the model, initialization data, microphysics scheme, and planetary boundary layer parameterization used. No single model or setup emerges as definitively best, but model timing of icing events compares well to observations.
Simulation of icing events over Gaspé regionWinterwind
Presentation by Jing Yang, Climate Research Division, Environment Canada on Winterwind 2012, session 3b. "Simulation of icing events over Gaspé region"
This is a brief presentation of the services offered under the E-Safetransfer S.A. Loyaly division (SafeLoyalty).
You can witness a unique innovation: prepaid cards that also gather client usage information to feed CRM platforms, enhancing customer satisfaction through bonuses, points or frequency based discounts.
Simulation of icing events over Gaspé regionWinterwind
Presentation by Jing Yang, Climate Research Division, Environment Canada on Winterwind 2012, session 3b. "Simulation of icing events over Gaspé region"
This is a brief presentation of the services offered under the E-Safetransfer S.A. Loyaly division (SafeLoyalty).
You can witness a unique innovation: prepaid cards that also gather client usage information to feed CRM platforms, enhancing customer satisfaction through bonuses, points or frequency based discounts.
In the first part of the talk, we will present a sensitivity analysis of a novel sea ice model. neXtSIM is a continuous Lagrangian numerical model that uses an elastobrittle rheology to simulate the ice response to external forces. The response of the model is evaluated in terms of simulated ice drift distances from its initial position and from the mean position of the ensemble. The simulated ice drift is decomposed into advective and diffusive parts that are characterized separately both spatially and temporally and compared to what is obtained with a free-drift model, i.e. when the ice rheology does not play any role. Overall the large-scale response of neXtSIM is correlated to the ice thickness and the wind velocity fields while the free-drift model response is mostly correlated to the wind velocity pattern only. The seasonal variability of the model sensitivity shows the role of the ice compactness and rheology at both local and Arctic scales. Indeed, the ice drift simulated by neXtSIM in summer is close to the free-drift model, while the more compact and solid ice pack is showing a significantly different mechanical and drift behavior in winter. In contrast of the free-drift model, neXtSIM reproduces the sea ice Lagrangian diffusion regimes as found from observed trajectories. The forecast capability of neXtSIM is also evaluated using a large set of real buoy’s trajectories. We found that neXtSIM performs better in simulating sea ice drift, both in terms of forecast error and as a tool to assist search-and-rescue operations. Adaptive meshes, as the one used in neXtSIM, are used to model a wide variety of physical phenomena. Some of these models, in particular those of sea ice movement, use a remeshing process to remove and insert mesh points at various points in their evolution. This represents a challenge in developing compatible data assimilation schemes, as the dimension of the state space we wish to estimate can change over time when these remeshings occur.
In the second part of the talk, we highlight the challenges that such a modeling framework represents for data assimilation setup. We then describe a remeshing scheme for an adaptive mesh in one dimension. The development of advanced data assimilation methods that are appropriate for such a moving and remeshed grid is presented. Finally we discuss the extension of these techniques to two-dimensional models, like neXtSIM.
Modelling wind flow in forested area - study by Meteodyn and Iberdrola Renewa...Jean-Claude Meteodyn
Meteodyn and Iberdrola Renovables have undertaken a systematic analysis of measurements data obtained in numerous sites, compared with Computation Fluid Dynamic approach. The analysis has consisted in highlighting the influence of several parameters on the shear defined as the vertical gradient of wind speed and the turbulence intensity at the wind turbine hub height. The influence is studied according to the forest description (density, height, shape of trees) and according to modelling parameters (Turbulent length scales, Dissipation parameter). Evaluation of the error ranges on wind shear and turbulence intensity is made according to the location of the wind turbines regarding the forest....
Comparison of satellite imagery based ice drift with wind model for the Caspi...Sergey Vernyayev
Many factors influencing the movement of ice such as wind, ice concentration, ice thickness,
roughness, water currents, Coriolis force, bathymetry, artificial and natural obstacles in the area. Current speeds in the Caspian Sea are relatively small and so the main driving force for ice movements is wind. Therefore, main goal of this work was to study wind-ice movement velocities dependence in the region and check how ice concentration and thickness influence on the movement of ice. A high number of measurements and observations was made to describe ice drift in the region, although the data was collected areas and usually not publicly available. In our work, we have used timely consequent optical and SAR satellite images to observe ice movements and its displacement over the area. Wind data for the same period and area was taken from wind models. Ice charts were prepared using visual interpretation of satellite imagery. Ice information (concentration, stage of development, floe size) were stored as vector data in SIGRID3 format. The described data has been correlated and analyzed. The analysis provided in the work can be used for the forecast of short term ice drift on the operational basis and can be the first step for creation of ice drift forecast model for the region of North Caspian Sea. The used data, methods and results of the study are described in this paper.
Optimal combinaison of CFD modeling and statistical learning for short-term w...Jean-Claude Meteodyn
After almost three decades of active research, short-term wind power forecasting is now considered as a mature field. It has been widely and successfully put into operation within the past ten years. Meteodyn with over a decade of experience in wind engineering has contributed to this spread with tens of wind farm equipped with forecast solutions around the world. Our next-generation short-term forecasting solution has been designed to makes the most of both a tailored micro-scale CFD modeling and advanced statistical learning. In the frame of our model design, various options have been considered and evaluated taking into account both model performance and operational constraints. Two main approaches for wind power forecasting are usually considered in the literature (and sometimes opposed): “physical” and “statistical”. It is widely admitted that an optimal combination of both is necessary to build a high performance forecasting system. However, behind "optimal combination" resides a wide variety of design options. We propose here to shed some light on what performances one should expect from several modeling options for combining physics (mesoscale/CFD modeling) and statistics (grey/black box statistical learning, phase/magnitude correction, data filtering). Case studies are taken from real wind farms in various climate and terrain conditions.
Mapping of icing in Sweden – On the influence from icing on wind energy produ...Winterwind
Presentation by Øyvind Byrkjedal, Kjeller Vindteknikk on Winterwind 2012, session 3a. "Mapping of icing in Sweden – On the influence from icing on wind energy production"
Energy Yield Assessment and Site Suitability using OpenFOAM - Crasto, Castell...Giorgio Crasto
A procedure has been implemented in order to assess the Annual Energy Production (AEP) of a wind farm. The pieces of software used for the porpoise are Octave, Meshlab and OpenFOAM. Two test cases are presented, in the second one also a first comparison with real production data.
Title: ''Solar 3D printing of lunar regolith "
Abstract: In-Situ Resource Utilization (ISRU) has become in the last decades one of the most prominent approaches for the building of a settlement on the Moon. The use of local resources to reduce up-mass, cost and risk of mission is now an essential consideration in future exploration scenarios. Within this trend, lunar regolith, the loose layer of crushed rock covering the Moon surface, has a key role to play. Its high metallic oxides content could offer a sustainable way of producing oxygen and it could also be used as a construction material via, for instance, a sintering process. By means of solar concentration, microwaves or radial heating elements, this process would create solid building elements that could be used for roads, launch pads or habitats. Additive manufacturing (AM) technology, commonly called 3D-printing, is widely used on Earth. Building parts layer by layer allows the realization of complex shapes, does not create wasted material, and requires low post-processing work. The shift from casting to AM in aerospace and automotive industries shows the leading place given today to such technology. AM in microgravity has already been used in space since 2014 with a first polymer 3D printer on-board the International Space Station (ISS). Combining AM with ISRU offers a way of building-up a permanent lunar outpost with a limited amount of upload from Earth. Proof of concepts using lunar regolith as main building material were given with the contour crafting and D-shape approaches. Both technologies create a mixture similar to concrete with the lunar soil and terrestrial consumable materials. Making any large-scale construction is therefore dependent on Earth shipments which is not viable for long term missions. In this work we demonstrate how, only using concentrated sunlight, we can 3D print a solid material from lunar regolith.
In the DLR solar oven, a custom solar 3D printer was constructed capable of sintering building elements using only lunar regolith simulants and concentrated sunlight. The realisation of various shapes has proven the concept, opening the path to further improvements and more challenging constructions designs.
In the first part of the talk, we will present a sensitivity analysis of a novel sea ice model. neXtSIM is a continuous Lagrangian numerical model that uses an elastobrittle rheology to simulate the ice response to external forces. The response of the model is evaluated in terms of simulated ice drift distances from its initial position and from the mean position of the ensemble. The simulated ice drift is decomposed into advective and diffusive parts that are characterized separately both spatially and temporally and compared to what is obtained with a free-drift model, i.e. when the ice rheology does not play any role. Overall the large-scale response of neXtSIM is correlated to the ice thickness and the wind velocity fields while the free-drift model response is mostly correlated to the wind velocity pattern only. The seasonal variability of the model sensitivity shows the role of the ice compactness and rheology at both local and Arctic scales. Indeed, the ice drift simulated by neXtSIM in summer is close to the free-drift model, while the more compact and solid ice pack is showing a significantly different mechanical and drift behavior in winter. In contrast of the free-drift model, neXtSIM reproduces the sea ice Lagrangian diffusion regimes as found from observed trajectories. The forecast capability of neXtSIM is also evaluated using a large set of real buoy’s trajectories. We found that neXtSIM performs better in simulating sea ice drift, both in terms of forecast error and as a tool to assist search-and-rescue operations. Adaptive meshes, as the one used in neXtSIM, are used to model a wide variety of physical phenomena. Some of these models, in particular those of sea ice movement, use a remeshing process to remove and insert mesh points at various points in their evolution. This represents a challenge in developing compatible data assimilation schemes, as the dimension of the state space we wish to estimate can change over time when these remeshings occur.
In the second part of the talk, we highlight the challenges that such a modeling framework represents for data assimilation setup. We then describe a remeshing scheme for an adaptive mesh in one dimension. The development of advanced data assimilation methods that are appropriate for such a moving and remeshed grid is presented. Finally we discuss the extension of these techniques to two-dimensional models, like neXtSIM.
Modelling wind flow in forested area - study by Meteodyn and Iberdrola Renewa...Jean-Claude Meteodyn
Meteodyn and Iberdrola Renovables have undertaken a systematic analysis of measurements data obtained in numerous sites, compared with Computation Fluid Dynamic approach. The analysis has consisted in highlighting the influence of several parameters on the shear defined as the vertical gradient of wind speed and the turbulence intensity at the wind turbine hub height. The influence is studied according to the forest description (density, height, shape of trees) and according to modelling parameters (Turbulent length scales, Dissipation parameter). Evaluation of the error ranges on wind shear and turbulence intensity is made according to the location of the wind turbines regarding the forest....
Comparison of satellite imagery based ice drift with wind model for the Caspi...Sergey Vernyayev
Many factors influencing the movement of ice such as wind, ice concentration, ice thickness,
roughness, water currents, Coriolis force, bathymetry, artificial and natural obstacles in the area. Current speeds in the Caspian Sea are relatively small and so the main driving force for ice movements is wind. Therefore, main goal of this work was to study wind-ice movement velocities dependence in the region and check how ice concentration and thickness influence on the movement of ice. A high number of measurements and observations was made to describe ice drift in the region, although the data was collected areas and usually not publicly available. In our work, we have used timely consequent optical and SAR satellite images to observe ice movements and its displacement over the area. Wind data for the same period and area was taken from wind models. Ice charts were prepared using visual interpretation of satellite imagery. Ice information (concentration, stage of development, floe size) were stored as vector data in SIGRID3 format. The described data has been correlated and analyzed. The analysis provided in the work can be used for the forecast of short term ice drift on the operational basis and can be the first step for creation of ice drift forecast model for the region of North Caspian Sea. The used data, methods and results of the study are described in this paper.
Optimal combinaison of CFD modeling and statistical learning for short-term w...Jean-Claude Meteodyn
After almost three decades of active research, short-term wind power forecasting is now considered as a mature field. It has been widely and successfully put into operation within the past ten years. Meteodyn with over a decade of experience in wind engineering has contributed to this spread with tens of wind farm equipped with forecast solutions around the world. Our next-generation short-term forecasting solution has been designed to makes the most of both a tailored micro-scale CFD modeling and advanced statistical learning. In the frame of our model design, various options have been considered and evaluated taking into account both model performance and operational constraints. Two main approaches for wind power forecasting are usually considered in the literature (and sometimes opposed): “physical” and “statistical”. It is widely admitted that an optimal combination of both is necessary to build a high performance forecasting system. However, behind "optimal combination" resides a wide variety of design options. We propose here to shed some light on what performances one should expect from several modeling options for combining physics (mesoscale/CFD modeling) and statistics (grey/black box statistical learning, phase/magnitude correction, data filtering). Case studies are taken from real wind farms in various climate and terrain conditions.
Mapping of icing in Sweden – On the influence from icing on wind energy produ...Winterwind
Presentation by Øyvind Byrkjedal, Kjeller Vindteknikk on Winterwind 2012, session 3a. "Mapping of icing in Sweden – On the influence from icing on wind energy production"
Energy Yield Assessment and Site Suitability using OpenFOAM - Crasto, Castell...Giorgio Crasto
A procedure has been implemented in order to assess the Annual Energy Production (AEP) of a wind farm. The pieces of software used for the porpoise are Octave, Meshlab and OpenFOAM. Two test cases are presented, in the second one also a first comparison with real production data.
Title: ''Solar 3D printing of lunar regolith "
Abstract: In-Situ Resource Utilization (ISRU) has become in the last decades one of the most prominent approaches for the building of a settlement on the Moon. The use of local resources to reduce up-mass, cost and risk of mission is now an essential consideration in future exploration scenarios. Within this trend, lunar regolith, the loose layer of crushed rock covering the Moon surface, has a key role to play. Its high metallic oxides content could offer a sustainable way of producing oxygen and it could also be used as a construction material via, for instance, a sintering process. By means of solar concentration, microwaves or radial heating elements, this process would create solid building elements that could be used for roads, launch pads or habitats. Additive manufacturing (AM) technology, commonly called 3D-printing, is widely used on Earth. Building parts layer by layer allows the realization of complex shapes, does not create wasted material, and requires low post-processing work. The shift from casting to AM in aerospace and automotive industries shows the leading place given today to such technology. AM in microgravity has already been used in space since 2014 with a first polymer 3D printer on-board the International Space Station (ISS). Combining AM with ISRU offers a way of building-up a permanent lunar outpost with a limited amount of upload from Earth. Proof of concepts using lunar regolith as main building material were given with the contour crafting and D-shape approaches. Both technologies create a mixture similar to concrete with the lunar soil and terrestrial consumable materials. Making any large-scale construction is therefore dependent on Earth shipments which is not viable for long term missions. In this work we demonstrate how, only using concentrated sunlight, we can 3D print a solid material from lunar regolith.
In the DLR solar oven, a custom solar 3D printer was constructed capable of sintering building elements using only lunar regolith simulants and concentrated sunlight. The realisation of various shapes has proven the concept, opening the path to further improvements and more challenging constructions designs.
Climate Impact of Software Testing at Nordic Testing DaysKari Kakkonen
My slides at Nordic Testing Days 6.6.2024
Climate impact / sustainability of software testing discussed on the talk. ICT and testing must carry their part of global responsibility to help with the climat warming. We can minimize the carbon footprint but we can also have a carbon handprint, a positive impact on the climate. Quality characteristics can be added with sustainability, and then measured continuously. Test environments can be used less, and in smaller scale and on demand. Test techniques can be used in optimizing or minimizing number of tests. Test automation can be used to speed up testing.
GraphSummit Singapore | The Art of the Possible with Graph - Q2 2024Neo4j
Neha Bajwa, Vice President of Product Marketing, Neo4j
Join us as we explore breakthrough innovations enabled by interconnected data and AI. Discover firsthand how organizations use relationships in data to uncover contextual insights and solve our most pressing challenges – from optimizing supply chains, detecting fraud, and improving customer experiences to accelerating drug discoveries.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Alt. GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using ...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Maruthi Prithivirajan, Head of ASEAN & IN Solution Architecture, Neo4j
Get an inside look at the latest Neo4j innovations that enable relationship-driven intelligence at scale. Learn more about the newest cloud integrations and product enhancements that make Neo4j an essential choice for developers building apps with interconnected data and generative AI.
Enchancing adoption of Open Source Libraries. A case study on Albumentations.AIVladimir Iglovikov, Ph.D.
Presented by Vladimir Iglovikov:
- https://www.linkedin.com/in/iglovikov/
- https://x.com/viglovikov
- https://www.instagram.com/ternaus/
This presentation delves into the journey of Albumentations.ai, a highly successful open-source library for data augmentation.
Created out of a necessity for superior performance in Kaggle competitions, Albumentations has grown to become a widely used tool among data scientists and machine learning practitioners.
This case study covers various aspects, including:
People: The contributors and community that have supported Albumentations.
Metrics: The success indicators such as downloads, daily active users, GitHub stars, and financial contributions.
Challenges: The hurdles in monetizing open-source projects and measuring user engagement.
Development Practices: Best practices for creating, maintaining, and scaling open-source libraries, including code hygiene, CI/CD, and fast iteration.
Community Building: Strategies for making adoption easy, iterating quickly, and fostering a vibrant, engaged community.
Marketing: Both online and offline marketing tactics, focusing on real, impactful interactions and collaborations.
Mental Health: Maintaining balance and not feeling pressured by user demands.
Key insights include the importance of automation, making the adoption process seamless, and leveraging offline interactions for marketing. The presentation also emphasizes the need for continuous small improvements and building a friendly, inclusive community that contributes to the project's growth.
Vladimir Iglovikov brings his extensive experience as a Kaggle Grandmaster, ex-Staff ML Engineer at Lyft, sharing valuable lessons and practical advice for anyone looking to enhance the adoption of their open-source projects.
Explore more about Albumentations and join the community at:
GitHub: https://github.com/albumentations-team/albumentations
Website: https://albumentations.ai/
LinkedIn: https://www.linkedin.com/company/100504475
Twitter: https://x.com/albumentations
Goodbye Windows 11: Make Way for Nitrux Linux 3.5.0!SOFTTECHHUB
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Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
Generative AI Deep Dive: Advancing from Proof of Concept to ProductionAggregage
Join Maher Hanafi, VP of Engineering at Betterworks, in this new session where he'll share a practical framework to transform Gen AI prototypes into impactful products! He'll delve into the complexities of data collection and management, model selection and optimization, and ensuring security, scalability, and responsible use.
Dr. Sean Tan, Head of Data Science, Changi Airport Group
Discover how Changi Airport Group (CAG) leverages graph technologies and generative AI to revolutionize their search capabilities. This session delves into the unique search needs of CAG’s diverse passengers and customers, showcasing how graph data structures enhance the accuracy and relevance of AI-generated search results, mitigating the risk of “hallucinations” and improving the overall customer journey.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
1. Mesoscale modelling of icing climate:
Sensitivity to model and model setup
Stefan Söderberg(1), Magnus Baltscheffsky(1), Hans Bergström(2), Petra
Thorsson(2), Per Undén(3), Esbjörn Olsson(3)
(1) WeatherTech Scandinavia AB, (2) Uppsala University, (3) SMHI
WeatherTech
Winterwind 2013 - Östersund
2. WeatherTech
Vindforsk V-313, Wind power in cold climates
- develop methods for estimating the icing climate and
production losses due to icing.
Tools:
- Observations
wind speed, temperature, ice load, wind farm data
- Ice load model
ISO 12494:2001 – Atmospheric icing on structures
- Mesoscale models:
WRF, COAMPS® (US Navy), AROME (e.g., SMHI),
different forcings, microphysics, and PBL schemes
Winterwind 2013 - Östersund
5. WeatherTech
Numerical experiment setup
Initial and lateral boundary conditions: Example of model domains
- i) NCEP Final Analysis (FNL from GFS)
ii) ERA Interim
iii) NCEP/NCAR Reanalysis
Vertical grid configuration:
- 11 levels in the lowest 300 m
Horizontal grid configuration:
- nested grids
Outer nest: 27 x 27 km2
3:1 nest ratio
Innermost nest: 1 x 1 km2
Winterwind 2013 - Östersund
6. WeatherTech
Model results – pressure
Large scale
weather systems
captured in a
similar way in all
three models
Winterwind 2013 - Östersund
7. WeatherTech
Model results – temperature
Differences found
during cold
periods and in
March.
Differences in
temperature close
to 0 oC have a
strong influence
on the ice load.
Winterwind 2013 - Östersund
8. WeatherTech
Model evaluation – brief summary
- Standard meteorological variables (wind, temperature,
pressure) are well captured by all three models
(AROME, COAMPS®, WRF).
- In the upcoming Vindforsk report statistics for all sites
are given.
Winterwind 2013 - Östersund
9. WeatherTech
Why so many models?
It is important to understand:
- A model is a model, not a perfect description of the real
world. Each model has its strengths and weaknesses.
- A modern weather forecast model should be viewed as
a model system.
- The results depend not only on choice of model but also
on model setup.
Winterwind 2013 - Östersund
11. WeatherTech
Modelled ice load – 3 models
Number of hours with active icing, ice growth > 10 g/h
2010/2011 2011/2012
AROME 138 337
COAMPS 290 641
WRF 389 604
Not the same model that gives the largest number of
hours with active icing over the two seasons.
Winterwind 2013 - Östersund
12. WeatherTech
WRF sensitivity study
Full name Category Description
FNL GFS Final analysis Forcing Final analysis of GFS operational forecast
ERA ERA Interim Forcing Re-analysis produced by ECMWF
NCAR NCEP/NCAR Forcing Re-analysis produced by NCEP/NCAR
WSM3 WRF Single-Moment 3-class Microphysics Simple, efficient scheme with ice and snow
processes
WSM6 WRF Single-Moment 6-class Microphysics A scheme with ice, snow and graupel
processes
Morr Morrison 2-moment Microphysics Prognostic mixing ratio for 6 classes and
double-moment ice, snow, rain and graupel
MYJ Mellor-Yamada-Janjic PBL Eta operational scheme. Prognostic turbulent
kinetic energy scheme with local vertical mixing
QNSE Quasi-Normal Scale PBL A TKE-prediction option that uses a new theory
Elimination for stably stratified regions
MYNN2 Mellor-Yamada Nakanishi and PBL Predicts TKE and other second-moment terms.
Niino Level 3
Winterwind 2013 - Östersund
21. WeatherTech
Conclusions
- Modelling ice load is not straight forward. The end result depend on
which model that is used and how the model is set up.
- Measuring ice is not trivial. State of the art instruments are not
accurate enough.
=> On a scientific level we cannot say which model and model setup
that is “the best”.
But (don’t despair!)
- The timing of the icing events are quite well captured.
- A newly developed power loss model have shown promising results
(Magnus Baltscheffsky at 10.30 tomorrow).
Winterwind 2013 - Östersund