Status of HyMeX th Joint Science Committee of the World Weather Research Programme – WMO Genève February 2011 Véronique Ducrocq On behalf of the HyMeX ISSC

 to improve our understanding of the water cycle, with emphases on the predictability and evolution of intense events  by monitoring and modelling: the Mediterranean coupled system (atmosphere-land-ocean), its variability (from the event scale, to the seasonal and interannual scales) and characteristics over one decade ( ) in the context of global change  to evaluate the societal and economical vulnerability to extreme events and the adaptation capacity. HyMeX objectives Science topics The five science Topics

EOP: Enhanced existing observatories and operational observing systems in the target areas of high-impact events: budgets and process studies (+ dedicated short field campaigns) LOP : Current operational observing system and observatories over the whole Mediterranean basin: budgets (data access) SOP: Special observing periods of high-impact events in selected regions of the EOP target areas (aircraft, R/V, balloons,…): process studies  A « Nested » approach necessary to tackle the whole range of processes and interactions and estimate budgets HyMeX Implementation Plan Observation strategy

 The LOP covers the whole Mediterranean basin  Three Target Areas (TA) canditates to the first EOP/SOP series, with embedded hydrometeorological and « upstream » atmospheric sites  Heavy precipitation, flash- flooding and flooding  Severe regional winds (Mistral, Bora, Tramontana,…) and cyclogeneses (Gulf of Genoa, …)  the four main regions of dense water formation and ocean convection The 3 TA covers all the intense phenomena:  Major rivers (Rhône, Evros/Maritsa), but also many small-medium size fast- response watersheds rivers,  Drought states (Israel,…)

 The HyMeX modelling strategy includes:  The improvement of convective-scale deterministic forecast systems to improve the prediction capabilities of Mediterranean high-impact weather event. HyMeX field campaigns should provide an unique high-resolution database to validate these new NWP systems: microphysical properties (polarimetric radars, aircraft measurements), marine boundary layer characteristics and air-sea fluxes measurements (buoys, research vessels), novel high-resolution moisture measurements (GPS delays on board ships, radar refractivity, water vapour from lidar, etc).  The design of high-resolution ensemble modelling systems dedicated to the study of the predictability of Mediterranean heavy precipitation and severe cyclogenesis, and their coupling with hydrological models to issue probabilistic forecast of the impact in terms of hydrological response. HyMex is proposed as a testbed for these ensemble systems  The set-up, validation and improvements of multi-components regional climate models dedicated to the Mediterranean area: ocean, atmosphere, land surface, hydrology in order to study interannual variability, past trends and future climate change  The development of new process modelling, parameterization development, novel data assimilation systems for the different Earth compartments. For example, improvement of air-sea flux parameterizations or development of data assimilation in cloud and precipitation systems are major objectives of HyMeX and part of the observation strategy is designed to serve these objectives. HyMeX Implementation Plan Modeling strategy

Highlights of WWRP-related activities Mesoscale modeling  Goal : Process understanding for improving the parameterizations of high- resolution NWP systems  Microphysical processes: Cloud-aerosol interaction (CCN, ICN), Cold-pool formation, Hydrometeor retrievial methods and validation of the microphysical parameterizations with in-situ and airbone microphysical observations  Turbulence, cloud and precipitation parameterisations (« grey zone ») MCS du 20 octobre: réflectivité radar à 16 UTC (dBz) Observations2.5 km run0.5 km run 1D Turb.3D Turb. reflectivity  Air-sea flux interactions: ocean-atmosphere coupled models to study the interaction and their importance to take them into account for short-range high-resolution NWP

Highlights of WWRP-related activities Ensemble prediction  THORPEX/TIGGE LAM: TIGGE LAM has proposed at the 4 th HyMeX Workshop to use the HyMEX SOPs as a test-bed for evaluating the LAM EPS performances and to have a collective contribution to answer scientific questions (mainly with WG3)  example of activities that should be conducted in synergy between programs: quantification of the additional benefits of multimodel LAM EPS with parameterized convection, sharing methodologies and use of same data standards (e.g. GRIB2, output parameter list).  Convection permitting ensemble prediction systems with explicit convection and horizontal resolution of a few kilometers:  Design, implementation and validation of, employed for short range predictions, is an important objectives of HyMeX  Coupling of these atmospheric ensemble systems with hydrological models to issue hydrological ensemble predictions is an other important objectives  HyMeX SOP serves as a testbed for these new EPS

Highlights of WWRP-related activities Ensemble prediction Streamflow simulated by the hydrological model ISBA-TOPMODEL for a flash-flood case over Southern France watersheds The model is driven by hourly precipitation forecast from an ensemble simulation based on the AROME model (resolution:2.5 km) - Global ARPEGE EPS used as LBC combined with ensemble data assimilation - Vié et al (2010) The model is driven by hourly precipitation fields derived from the AROME NWP operational suite - A object-oriented perturbation method is applied to the determinist QPF – Vincendon et al (2011) ensemble spread between q 0.25 and q 0.75 ensemble median AROME determinist run ensemble members observations Streamflow simulated using: Legend:

Highlights of WWRP-related activities Mesoscale data assimilation  Goals :  Preparation of the real-time operating mesoscale models over the Mediterranean during the field campaigns  Incl. Real Time assimilation of EOP-SOP specific observation Datasets (Drifting balloons,…)  Improvements in satellite radiance assimilation : – Mesoscale observation operator (Duffourg et al 2010), – Over the Sea, Enhanced density (correlations in observation errors), – Over land, surface emissivity parametrisation and retrieval of skin Temperature for hyperspectral sounders –In cloudy conditions, use of model cloud variables for the brightness temperature simulation  More European radar data assimilated in AROME WMED (work on radar data format for assimilation purposes) AROME-WMED

Highlights of WWRP-related activities Mesoscale data assimilation  Assimilation of new observational data types, in particular those directly related to precipitation: – Water vapour lidar (Bielli et al, 2011) – Moisture related data from wind profilers – Radar refractivity and polarimetric parameters from weather radar, – Dual polarization radar data – Ground based radiometric data  Background error modelling – Comparison of background error statistics (AROME, WRF…) – Heterogeneous background error covariances (rainy/non-rainy areas): comparison, modelling (Montmerle and Berre, 2010) – Dataset to study background error statistics for hydrometeors (Michel et al 2011)

Highlights ofn WWRP/WCRP-related activities Regional climate modeling  HyMeX regional climate modeling activities:  contribute to the MED-CORDEX initiative included in the WCRP/CORDEX program, which aims to improve the coordination of international efforts on regional climate downscaling.  MED-CORDEX will make use of both regional atmospheric climate models and regional coupled systems. Strong air-sea interactions take place in the Mediterranean basin, motivating the use of coupled regional models.  Two main phases have been envisaged within the MED-CORDEX action: – performing state-of-the-art coupled runs feeding the next IPCC report (AR5) by mid 2011; – developing new experiments to test new components and improved schemes, based on the HyMeX field campaign outcomes and process- oriented diagnostics (e.g. water budget of the Mediterranean Sea)

Highlights on WWRP-related activities Regional climate modeling

HyMeX organization Main Phases and associated documents Phase 1 White Book International Science Plan (ISP) Phase International Implementation Plan (IIP) International HyMeX Workshops May th HyMeX Workshop LOP Sept EOP SOP HyMeX Operations HyMeX Preparation Phase A

 Data policy defined in 2010 by the HyMeX ISSC:  International membership: Over 400 members from about 20 countries registered to the Science Working Groups and Implementation Task Teams. A national level structuring for France, Italy, Spain, Germany, Croatia, Netherlands, Israel. In France, HyMeX is inserted in a program cluster, called MISTRALS, about the monitoring and evolution of the habitability in Mediterranean (HyMeX sponsors: CNRS/INSU, Météo-France, CNES, INRA, CEMAGREF). Other MISTRALS programs: Charmex, Mermex, Termex, Sicmed, Paleomex, Biodivmex Core users Associated users Public domain Associated scientists are involved in scientific studies that meet the HyMeX objectives or educational activities related to HyMeX, access to the data once the period of core- user exclusive access is over Core users are HyMeX funded scientists, they are granted exclusive access for a period of 2-years HyMeX organization International organization

 WMO status  HyMeX is endorsed by the WWRP/THORPEX program (high-impact weather events)  HyMeX is a a Regional Hydroclimate Project (RHP) of WCRP/GHP (GEWEX Hydroclimatology Projects 3 sites: CV (France), NE (Italy), IS (Israel)  MED-CORDEX regional climate modeling activities of HyMeX are part of WCRP/CORDEX HyMeX organization International organization

The 5th HyMeX Workshop will take place in Punta Prima, Menorca, Spain, May 2011 Hotel Barcelo Pueblo WWRP participation is welcome