A first-of-its-kind multi-model convection permitting ensemble for investigating convective phenomena over Europe and the Mediterranean

Erika Coppola (1) , Stefan Sobolowski (2) , E. Pichelli (1) , F. Raffaele (1) , B. Ahrens (3) , I. Anders (4) , N. Ban (5) , Sophie Bastin (6) , M. Belda (7) , D. Belusic (8) , A. Caldas-Alvarez (9) , R. M. Cardoso (10) , S. Davolio (11) , A. Dobler (12) , J. Fernandez (13) , L. Fita (14) , Q. Fumiere (15) , F. Giorgi (1) , K. Goergen (16, 17) , I. Güttler (18) , T. Halenka (7) , D. Heinzeller (19, 20) , Ø. Hodnebrog (21) , D. Jacob (22) , S. Kartsios (23) , E. Katragkou (23) , E. Kendon (24) , S. Khodayar (25) , H. Kunstmann (19, 26) , S. Knist (17, 27) , A. Lavín-Gullón (13) , P. Lind (8) , T. Lorenz (2) , D. Maraun (28) , Louis Marelle (21) , E. Van Meijgaard (29) , J. Milovac (30) , G. Myhre (21) , H.-J. Panitz (9) , M. Piazza (28) , M. Raffa (31) , T. Raub (22) , B. Rockel (32) , C. Schär (5) , K. Sieck (22) , P. M. M. Soares (10) , S. Somot (15) , L. Srnec (18) , P. Stocchi (33) , M. H. Tölle (34) , H. Truhetz (28) , R. Vautard (35) , H. De Vries (29) , K. Warrach-Sagi (30)

1 ICTP - Abdus Salam International Centre for Theoretical Physics [Trieste]
2 BCCR - Bjerknes Centre for Climate Research
3 Goethe-Universität Frankfurt am Main
4 ZAMG - Central Institute for Meteorology and Geodynamics [Vienna]
5 IAC - Institute for Atmospheric and Climate Science [Zürich]
6 SPACE - LATMOS
7 Faculty of Mathematics and Physics [Praha/Prague]
8 SMHI - Swedish Meteorological and Hydrological Institute
9 IMK-TRO - Institut für Meteorologie und Klimaforschung - Troposphärenforschung
10 Instituto Dom Luiz
11 ISAC - Istituto di Scienze dell'Atmosfera e del Clima
12 MET - Norwegian Meteorological Institute [Oslo]
13 Grupo de Meteorología de Santander
14 CIMA - Centro de Investigaciones del Mar y la Atmósfera
15 CNRM - Centre national de recherches météorologiques
16 IBG - Institute of Bio- and Geosciences [Jülich]
17 HPSC TerrSys - Centre for High-Performance Scientific Computing in Terrestrial Systems
18 DHMZ - Croatian Meteorological and Hydrological Service
19 IMK-IFU - Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung
20 ESRL - NOAA Earth System Research Laboratory
21 CICERO - Center for International Climate and Environmental Research [Oslo]
22 GERICS - Climate Service Center [Hambourg]
23 Department of Meteorology and Climatology [Thessaloniki]
24 MOHC - Met Office Hadley Centre
25 IMK - Institute for Meteorology and Climate Research
26 Institut für Geographie [Augsburg]
27 Meteorologisches Institut [Bonn]
28 WEGC - Wegener Center for Climate and Global Change
29 KNMI - Royal Netherlands Meteorological Institute
30 IPM - Institut für Physik und Meteorologie [Stuttgart]
31 CMCC - Euro-Mediterranean Center on Climate Change
32 GKSS - Helmholtz-Zentrum Geesthacht
33 ISAC - Istituto di Scienze dell'Atmosfera e del Clima [Bologna]
34 Klimatologie, Klimadynamik und Klimawandel [Giessen]
35 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]

A recently launched project under the auspices of the World Climate Research Program’s (WCRP) Coordinated Regional Downscaling Experiments Flagship Pilot Studies program (CORDEX-FPS) is presented. This initiative aims to build first-of-its-kind ensemble climate experiments of convection permitting models to investigate present and future convective processes and related extremes over Europe and the Mediterranean. In this manuscript the rationale, scientific aims and approaches are presented along with some preliminary results from the testing phase of the project. Three test cases were selected in order to obtain a first look at the ensemble performance. The test cases covered a summertime extreme precipitation event over Austria, a fall Foehn event over the Swiss Alps and an intensively documented fall event along the Mediterranean coast. The test cases were run in both “weather-like” (WL, initialized just before the event in question) and “climate” (CM, initialized 1 month before the event) modes. Ensembles of 18–21 members, representing six different modeling systems with different physics and modelling chain options, was generated for the test cases (27 modeling teams have committed to perform the longer climate simulations). Results indicate that, when run in WL mode, the ensemble captures all three events quite well with ensemble correlation skill scores of 0.67, 0.82 and 0.91. They suggest that the more the event is driven by large-scale conditions, the closer the agreement between the ensemble members. Even in climate mode the large-scale driven events over the Swiss Alps and the Mediterranean coasts are still captured (ensemble correlation skill scores of 0.90 and 0.62, respectively), but the inter-model spread increases as expected. In the case over Mediterranean the effects of local-scale interactions between flow and orography and land–ocean contrasts are readily apparent. However, there is a much larger, though not surprising, increase in the spread for the Austrian event, which was weakly forced by the large-scale flow. Though the ensemble correlation skill score is still quite high (0.80). The preliminary results illustrate both the promise and the challenges that convection permitting modeling faces and make a strong argument for an ensemble-based approach to investigating high impact convective processes.

Mots clés: Convection-permitting; Ensemble models; Climate applications

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]; Climatologie

Erika Coppola, Stefan Sobolowski, E. Pichelli, F. Raffaele, B. Ahrens, et al.. A first-of-its-kind multi-model convection permitting ensemble for investigating convective phenomena over Europe and the Mediterranean. Climate Dynamics, 2020, 55, pp.3-34. ⟨10.1007/s00382-018-4521-8⟩. ⟨insu-01923722⟩