The climate model: EC-Earth 3

The climate model used for simulations is EC-Earth version 3.1, a state-of-the-art, high-resolution earth-system model, developed by a large consortium of European research institutions and researchers. The EC-Earth model contains advanced, robust and validated components for the atmosphere (the ECMWF IFS model), the ocean (NEMO; Madec 2008), sea ice (LIM; Fichefet and Morales Maqueda 1997) and land processes (H-Tessel; Balsamo et al. 2009). EC-Earth has been validated and applied in a series of recent publications (Hazeleger 2000 and 2012; Johnston 2011; Sterl 2011; Wouters 2011). Version 3 of EC-Earth has been recently officially released, and includes several important updates in the components, including IFS 36r4, NEMO version 3 and an improved sea-ice scheme LIM3.  The model consists of two separate codes running in MPMD mode, the ocean model NEMO and the atmospheric model IFS. IFS is a parallel spectral atmospheric model developed at ECMWF, highly optimized, tested, and used for operational production of forecasts at high resolution. NEMO is based on the OPA physical ocean model based on finite differences with MPI communication. The coupler OASIS3 (Valcke 2006) synchronizes the two submodels and manages the exchange and interpolation of physical coupling fields. Communications between the models and the OASIS3 coupler is enabled by a set of library routines based on the MPI1 library. All models are written in C and FORTRAN. In this project we will use EC-Earth version 3.1, released in April 2014,  the result of over 18 months of testing and tuning of the model by the consortium. 

The code has been already been successfully implemented and tested on different supercomputing platforms by groups participating in the consortium. The group at ISAC-CNR has implemented and used EC-Earth3 on different supercomputing platforms including SuperMUC at LRZ, Germany and Fermi/CINECA.

The institution of three of the partners (ISAC-CNR) is a full contributing (core) partner of the EC-Earth consortium and has signed the relevant Memorandum of Understanding and Letter of Intent with the consortium. NEMO (open source) and OASIS3 (LGPL license) are integral part of the EC-Earth model and distributed together with the model.