THORPEX European Plan D. Majewski, DWD, Germany THORPEX - Overview Aims and structure of THORPEX European Plan Some comments on each section Possible contributions from European Met. Services

THORPEX – Overview, Part I THORPEX: a Global Atmospheric Research Programme for the 21st Century. International research programme to accelerate improvements in the accuracy of 1-day to 2-week high-impact weather forecasts. High-impact weather forecasts are defined by their effect on society, the economy and the environment. The programme developed from the initially planned experiment called “The Observing System Research and Predictability Experiment (THORPEX)” into a broad programme in atmospheric and related sciences. International collaboration among academic institutions, operational forecast centres and users of forecast products.

THORPEX – Overview, Part II THORPEX is part of the WMO World Weather Research Programme (WWRP). THORPEX International Core Steering Committee (ICSC): Members are nominated by Permanent Representatives of countries with the WMO. Research objectives are developed under four sub-programmes: 1) Predictability and Dynamical Processes (PDP, global-to- regional influences on the evolution and predictability of weather systems); 2) Observing Systems (OS, global observing-system design and demonstration); 3) Data Assimilation and Observing Strategies (DAOS, targeting and assimilation of observations); 4) Societal and Economic Research and Applications (SERA, societal, economic, and environmental benefits of improved forecasts).

THORPEX – Overview, Part III THORPEX Interactive Grand Global Ensemble (TIGGE) THORPEX Website: THORPEX International Research Implementation Plan: mentation_plan_v1_002.pdf mentation_plan_v1_002.pdf Funding of THORPEX is the big issue (estimated costs of between 1.2 and 1.8 Mill. US$ per year). THORPEX Trust Fond:

Aims of THORPEX European Plan Version 1.0 (7 June 2007) by G. Craig, E. Richard et al. Builds on THORPEX Science Plan, focuses on implementation. Prioritisation of the scientific aims relative to European requirements and recommendations for actions to be initiated within Europe. Reflect the special circumstances of meteorological research in Europe (large number of nations, trans-national organizations like EUMETNET, EUMETSAT, ECMWF). Significant emphasis on limited area modelling and multi-model ensembles.

Structure of THORPEX European Plan 1.Needs and requirements for weather research in Europe, based on societal and economic applications (p3 – p4). 2.Scientific challenges - Meteorological phenomena of greatest interest in Europe (p5 – p15). 3.Action plans for PDP (p16 – p18), OS+DAOS (p19 – p23), SERA (p24 – 25) and TIGGE (p26 – 33). 4.Organization and cooperation (p34).

Some comments on Section 1 (p2) Three larger Met. Services (DWD, Météo France, UKMO) and ECMWF with global NWP systems. Many National Met. Services with regional NWP systems, mainly organized in consortia (ALADIN, COSMO, HIRLAM, LACE, UKMO) developing unique systems. Diversity of modelling approaches (spectral and grid point, hydrostatic and non-hydrostatic, whole range of physical parameterizations; different data assimilation techniques). Operational NWP systems made available to universities in many countries. Eastern Europe not yet fully integrated in EUMETNET. Private service providers for many commercial activities (e.g. media, ship routing).

EUMETNET – Members (2006)

Some comments on Section 2 (p3 – p4) Economic value of ’ordinary’ vs. ‘high impact’ weather forecasts, e.g. for energy consumption and trading, traffic management. High impact weather: Main duty of National Met. Services. Flow of information from NMS to the emergency response managers on local level and to the public should be mentioned. Meteoalarm: Diversity of applications based on NWP data, e.g. hydrological, agrometeorological models, road condition, tracer transport. Automation of the forecasting process and the role of the trained forecaster. Role of private service providers with respect to high impact weather (e.g. cooperation with insurance companies).

EUMETNET - Meteoalarm Weather warnings: Europe: Austria AT France FR Spain ES United Kingdom UK awareness types: Display: Awareness Reports You can find detailed information about the warnings in the awareness reports issued for each country. Select the relevant country. 10 elements 5 colours

Some comments on Section 3 (p5 – p15) Extensive list of different meteorological systems leading to high impact weather is given first. From SERA point of view, a better approach would be to list high impact weather elements (close to the surface), e.g. strong mean wind/gusts, strong vertical wind shear, heavy precipitation (and rapid snow melt) leading to flooding, heavy snowfall, freezing rain, hail, lightning, extremely high (or low) temperature, draughts, fog/poor visibility, prolonged periods of strong temperature inversions leading to poor air quality; plus coastal event, forest fire, avalanches (from Meteoalarm page). Relate these weather elements to certain meteorological features (which might differ from region to region); study their genesis, life cycle and predictability. Quantify damages due to these weather elements; order them according to the possible damage reduction due to improved forecasts.

Some comments on Section 4 (p16 – p33) PDP (p16 – p18) A1: T-NA(W)DEX far beyond European capabilities because measurements mainly in the western Atlantic; without US involvement not doable. Autumn not the best season for measurements of disturbances of the North Atlantic waveguide, winter would be better. A2+A3: Strongly supported. A4: More on Ensembles, e.g. multi-model (INM-SREPS, PEPS) vs. single model EPS; distinguish different forecast ranges: 0-3d, 3-5d, 5-14d. A5: Strongly supported.

OS/DAOS (p19 – p23) Diversity of DA-methods in Europe: Disadvantage or chance? What is the general “European data assimilation and observing strategy”? Is day 5 to 14 most important for high impact weather? SERA studies should answer this question! In Europe, short range (0- 3d) forecasts have high priority (because of LAMs) More DA for surface parameters strongly supported! A1 – A7: Strongly supported. A5: More on ETKF! Additional Actions: Assimilation of radar data in km-scale models. Surface DA, including the use of data from special observatories.

SERA (p24 – p25) See comments on Section 3: As a starting point list high impact weather elements and quantify the corresponding damage in different European regions. Order them according to the possible damage reduction due to improved forecasts on different temporal scales. Indicate forecast lead time and temporal/spatial accuracy (as well as FAR and POD) needed by responsible users to take appropriate actions. For the Actions: Why emphasis only on the medium range? High impact forecasts probably mainly short range due to the accuracy required (cost/loss ratio of prevention/damage). Additional Actions: Study flow of information from NMS to decision makers to public for high impact weather in all European countries. Improve cross- national flow of information. Role of private service providers in high impact weather forecasts (“single voice”?)

TIGGE (p26 – p33) Europe is well-placed to contribute to the regional component of TIGGE. The general statement “deterministic short range forecasts give reliable prediction of synoptic scale features” is often not true for high impact weather systems over Europe, e.g. track and intensity of cyclones. Evaluate the value of multi-model ensembles (INM-SREPS, PEPS)! Table 1 items are rather incoherent (cyclones, QPF, polar influences). Action 3: TIGGE-LAM up to 3 days; dx~10 km. Global EPS normally diverge > 2d; do we really need LBC data from global EPS? Initial data from EPS may be enough! Huge data volume for LBC! Evaluate SRNWP PEPS, INM SREPS, COSMO SREPS, GLAM EPS first before taking steps towards TIGGE-LAM!

TIGGE (p26 – p33) Action 5: Design a European TIGGE-LAM up to 3 days; dx~10 km in conjunction with EUMETNET SRNWP! Here we have to give input! Who, when, how? Actions Strongly supported.

Some comments on Section 5 (p34) Why Eastern Europe separately? The “Iron Wall” does not exist since more than 15 years! Concrete involvement of the European National Meteorological services in THORPEX European Plan! Financing of THORPEX still a critical issue! For the Appendix: List of NWP consortia in Europe including their Websites. List of NWP systems in all European countries (plus ECMWF).

Final remarks The paper does not cover (except on p27) the general improvement of the models by work e.g. on numerics or physics. The paper concentrates too much on medium range forecasts; this is not the main forecast range of LAMs. The paper does not discuss lead times for high impact weather. The content of the paper is too inhomogeneous, sometimes very detailed (e.g. mentioning a certain plane), sometimes too general. The lead authors should try to homogenize the paper. What’s about the private service providers? Should they be included in THORPEX European Plan, e.g. via SERA Actions?

Possible contributions from European Met. Services ???