A. Baklanov, DMI COST-728 workshop on “Model urbanization strategy” MetO, Exeter, UK, 3-4 May 2007 The aim of the workshop is to discuss and make recommendations on the best practice and strategy for urbanisation of different types of meteorological and air quality models. A logical continuation of the Special Section and Round Table on "Urban sub-layer parameterisations in meteorological, climate and environmental models" of the 6th International Conference on Urban Climate (ICUC- 2006) in Göteborg, Sweden, June 12th - 16th 2006

A. Baklanov, DMI International organising committee: Maria Athanassiadou (UKMO), Alexander Baklanov (Danish Meteorological Institute), Bob Bornstein (Jose State University, USA), Peter Clark, (UKMO), Stefano Galmarini (Joint Research Center, Italy), Sven-Erik Gryning (Risø NL, Denmark), Alberto Martilli (CIEMAT, Spain), Ranjeet Sokhi (University of Hertfordshire, UK), Sergej Zilitinkevich (Helsinki University, Finland).

A. Baklanov, DMI European COST Actions ( ): 728: "Enhancing Meso-scale Meteorological Modelling Capabilities for Air Pollution and Dispersion Applications" Coord. – Ranjeet S Sokhi, University of Hertfordshire WG1: Meteorological parameterization/ applications (Maria Athanassiadou, Met Office) WG2: Integrated systems of MetM and CTM: strategy, interfaces and module unification (Alexander Baklanov, DMI) WG3: Mesoscale models for air pollution and dispersion applications (Mihkail Sofiev, FMI) WG4: Development of evaluation tools and methodologies (Heinke Schluenzen, University of Hamburg) Action 732: ‘Quality Assurance and Improvement of Micro- Scale Meteorological Models’ Coord. –Michael Schatzmann, University of Hamburg

A. Baklanov, DMI Special Section: "Urban sublayer parameterisations in meteorological, climate and environmental models" on ICUC-2006, Göteborg, Sweden, June 15th 2006, 9:00-18:00 The main focuses of Section are: - Urban physiographic data classification and usage of satellite data on surface, - Parameterisations and models of urban soil/heat, roughness sublayer and internal boundary layers, - Urbanisation of meso-meteorological and numerical weather prediction models, - Urban sublayer models, parameterisations and meteo-preprocessors for urban air quality and emergency preparedness models, - Urban effects incorporation into regional climate models.

A. Baklanov, DMI Round Table Discussion (D1 section, 16:45) "Urban sublayer parameterisations in meteorological, climate and environmental models“ Main question to discuss: What approaches and sublayer parameterisations are the most suitable/ applicable for different types of the meteorological, climate and environmental models? Depend on the scales, items (for operational forecast, assessments or research), etc. Joint view & recommendations for urbanization of different models : a) Urban meteorology, b) Numerical weather prediction (NWP), c) Local and regional climate, d) Environmental / air quality, e) Emergency preparedness, f) Urban-scale research models, Discussion on urban databases (morphology, verification and intercomparison) Possible prototype(s) for models urbanisation for modellers community.

A. Baklanov, DMI Conclusions There is a need to build a common strategy(ies) for urbanisation of different types of models (NWP, UAQ, climate, etc. - they need different parameterisations/ approaches). It was decided to build a world-wide working group on 'Model urbanization strategy'. Further WG activities would include the following main topics: 1. Urban morphology and databases, 2. Parameterisations of urban canopy, 3. Strategy for urbanization of different types of models, 4. Verification and city case studies / experiments. There are several ideas under what umbrella to organize this group. COST728 as one of the options. It could be also WMO (e.g. GURME), JRC, NCAR, US EPA, etc.

A. Baklanov, DMI The initial core group was suggested: Alexander Baklanov (DK), Bob Bornstein (USA), Martin Best (UK), Jason Ching (USA), Sue Grimmond (UK), Chen Fei (USA), Alberto Martilli (Spain), Valery Masson (France), Patrice Mestayer (France), Kanda Manabu (Japan). To arrange a web-portal for information exchange between different groups of the WG (e.g. on existing sites, like Fumapex or Cost728) The 'Model urbanization' Special section results can be very useful for further model 'urbanization' work in many organizations and countries, so it would be nice to give these more accessible. Suggestions to publish it : (i) e.g. as a COST publication (like in COST 715), in form of proceedings (only a few 4pp abstracts were published in ICUC6 Preprints) or as an overview inviting some participants (to agree with MC of COST728); (ii) as a special web-presentation of the Section e.g. on ICUC/IAUC, FUMAPEX, COST728 web-site with all presentations (of course, who will agree). Conclusions (cont.)

A. Baklanov, DMI Overall Roundtable Article for IAUC Newsletter The following structure and moderators in brackets: 1. General information and problem statement (Alexander and Bob) 2. Statement of databases (Jason) 3. Parameterisations of urban canopy (Alberto, Patrice), links with CFD, LES, DNS (Kanda) 4. Implementation to (urbanization of) different types of models (Valery,...) 5. Verification and city case studies (Martin, Bob,...) 6. Conclusions and recommendations (all)

A. Baklanov, DMI Exeter COST728 Workshop Exeter COST728 Workshop Main emphasis on following main topics: 1. Urban morphology and databases, 2. Parameterisations of urban canopy, 3. Strategy for urbanization of different types of models, 4. Verification and city case studies / experiments.

A. Baklanov, DMI Discussions on the following questions are especially welcome: 1.Variables we want to model (and degree of precision) for different applications (air quality, emergency response, urban climatology, weather forecast, etc.), e.g: - Do we want values within the canopy or only total fluxes? - Do we want good turbulent values? - For dispersion applications, do we want mean concentrations or also variances? 2.Best way to evaluate the capability of the paramterizations to model the relevant variables i.e. - wind tunnel experiments - role of the CFD/LES models - urban measurement champagnes 3.Ways to realise and improve the parameterizations - For dynamics: porosity models, dispersive stress, role of CFD/LES models. - For energy: need for building energy models

A. Baklanov, DMI Programme of the workshop Welcome from UKMO Overview of results from the ICUC-06 'Model urbanisation' Roundtable Lectures for the main topics (30-40 min each) Presentations by participants (20 min each) Discussions / Round table to build a joint strategy, recommendations and requirements COST-728 publication of the Workshop materials Plans for Network/WG on 'Model urbanization strategy' and web-portal for information exchange

A. Baklanov, DMI Main discussion topics (and conveners): 1.Urban morphology and databases (Jason Ching,..) 2.Parameterisations of urban canopy (Alberto Martilli, …), 3.Strategy for urbanization of different types of models (Peter Clark, …) 4.Verification and city case studies / experiments (Bob Bornstein, ….)

A. Baklanov, DMI Some slides for discussion

A. Baklanov, DMI Discussions topics and questions: 1.Variables we want to model (and degree of precision) for different applications (air quality, emergency response, urban climatology, weather forecast, etc.), e.g: - Do we want values within the canopy or only total fluxes? - Do we want good turbulent values? - For dispersion applications, do we want mean concentrations or also variances? 2.Best way to evaluate the capability of the paramterizations to model the relevant variables i.e. - wind tunnel experiments - role of the CFD/LES models - urban measurement champagnes 3.Ways to realise and improve the parameterizations - For dynamics: porosity models, dispersive stress, role of CFD/LES models. - For energy: need for building energy models 1. Urban morphology and databases (Jason Ching,..) 2. Parameterisations of urban canopy (Alberto Martilli, …), 3. Strategy for urbanization of different types of models (Peter Clark, …) 4. Verification and city case studies / experiments (Bob Bornstein, ….)

A. Baklanov, DMI Strategy for model urbanization WMO, GURME Model scales (regional, city, local, micro, …) Climate models (regional, urban,..) Research meso- meteorological models Numerical weather prediction models Atmospheric pollution models (city-scale) Emergency preparedness models Meteo-preprocessors (or post-processors) Different requirements for NWP and environmental models (e.g. in UBL structure)

A. Baklanov, DMI Integrated Fumapex urban module for NWP models including 4 levels of complexity of the NWP 'urbanization'

A. Baklanov, DMI Urbanization of the FUMAPEX NWP models

A. Baklanov, DMI Approaches applicability The first module is the cheapest way of “urbanising” the model and can be easily implemented into operational NWP models as well as in Regional Climate Models. The second module is a relatively more expensive (≈ 5-10 % computational time increase), but it gives a possibility to consider the energy budget components and fluxes inside the urban canopy. However, this approach is sensitive to the vertical resolution of NWP models and is not very effective if the first model level is higher than 30 meters. Therefore, the increasing of the vertical resolution of current NWP models is required. The third module is considerably more expensive computationally than the first two modules (up to 10 times!). However, it provides the possibility to accurately study the urban soil and canopy energy exchange including the water budget. Therefore, the second and third modules are recommended for use in advanced urban-scale NWP and meso-meteorological research models.

A. Baklanov, DMI Further improvements The current versions of the considered urban modules have several shortcomings and have to be improved and further developed. For the first approach (module 1), the complemented analytical model for wind velocity and diffusivity profiles inside the urban canopy (Zilitinkevich and Baklanov, 2005) has to be tested with different NWP models and meteorological preprocessors, and carefully verified vs. experimental data for different regimes. Besides, it is advisable to extend this model for temperature and humidity profiles. The current version of the second module (BEP) does not consider the moisture and latent heat fluxes and does not completely incorporate the anthropogenic heat flux. Therefore, these should be included into a new version of the BEP module. Besides, recalculation of accessible meteorological fields in the lowest sub-layers is necessary. The third module (SM2-U) needs further development considering the building drag effect (it is realised in module 4), whereas snow and ice have to be included for NWP during winter periods, especially for northern areas. The existing version of this module, when run for every grid-cell, is too expensive for operational NWP models, therefore the module has to be optimised by making calculations only for the urban cells. The combined module (#4), including all non-overlapping mechanisms from the SM2-U and BEP models, have to be further tested.

A. Baklanov, DMI Urban Meteo-Preprocessor High-resolution urban-scale NWP data Calculation of effective roughnesses (for momentum and scalars) and displacement height Parameterization of wind and eddy profiles in urban canopy layer Calculation of anthropogenic and storage urban heat fluxes Prognostic parameterizations for Mixing Height Improved sigma parameterization for SBL Urban module as post-processor for NWP data

A. Baklanov, DMI Key parameters for urban models of different scales (COST715)

A. Baklanov, DMI Ways to resolve the UBL structure 1. Obstacles-resolved numerical models - CFD => turbulent closure, bc, geometry, etc. - LES, …, DNS - simple box models 2. Parameterization of sub-grid processes - theoretical - experimental - numerical 3. Downscaling of models / Nesting techniques - NWP-local-scale meteorological models - Mesoscale models – CFD tools - Mesoscale models – Parameterized models

A. Baklanov, DMI Extended FUMAPEX scheme of the UAQIFS including feedbacks Improvements of meteorological forecasts (NWP) in urban areas, interfaces and integration with UAP and population exposure models following the off-line or on-line integration