Climate SPHINX: evaluating the impact of resolution and stochastic physics parameterisations in climate simulations
Paolo Davini1,2, Jost von Hardenberg2, Susanna Corti3, Hannah M. Christensen4, Stephan Juricke4, Aneesh Subramanian4, Peter A. G. Watson4, Antje Weisheimer4,5, and Tim N. Palmer41Laboratoire de Météorologie Dynamique/IPSL, Ecole Normale Supérieure, Paris, France 2Institute of Atmospheric Sciences and Climate (ISAC-CNR), Torino, Italy 3Institute of Atmospheric Sciences and Climate (ISAC-CNR), Bologna, Italy 4Atmospheric, Oceanic and Planetary Physics, University of Oxford, Oxford, UK 5National Centre for Atmospheric Science (NCAS), University of Oxford, Oxford, UK
Received: 07 May 2016 – Accepted for review: 20 Jun 2016 – Discussion started: 23 Jun 2016
Abstract. The Climate SPHINX (Stochastic Physics HIgh resolutioN eXperiments) project is a comprehensive set of ensemble simulations aimed at evaluating the sensitivity of present and future climate to model resolution and stochastic parameterisation. The EC-Earth Earth-System Model is used to explore the impact of stochastic physics in a large ensemble of 30-year climate integrations at five different atmospheric horizontal resolutions (from 125 km up to 16 km). The project includes more than 120 simulations in both a historical scenario (1979–2008) and a climate change projection (2039–2068), together with coupled transient runs (1850–2100). A total of 20.4 million core hours have been used, made available from a single year grant from PRACE (the Partnership for Advanced Computing in Europe), and close to 1.5 PBytes of output data have been produced on SuperMUC IBM Petascale System at the Leibniz Supercomputing Center (LRZ) in Garching, Germany. About 140 TBytes of post-processed data are stored on the CINECA supercomputing center archives and are freely accessible to the community thanks to an EUDAT Data Pilot project. This paper presents the technical and scientific setup of the experiments, including the details on the forcing used for the simulations performed, defining the SPHINX v1.0 protocol. In addition, an overview of preliminary results is given: an improvement in the simulation of Euro-Atlantic atmospheric blocking following resolution increases is observed. It is also shown that including stochastic parameterisation in the low resolution runs helps to improve some aspects of the tropical climate – specifically the Madden-Julian Oscillation and the tropical rainfall variability. These findings show the importance of representing the impact of small scale processes on the large scale climate variability either explicitly (with high resolution simulations) or stochastically (in low resolution simulations).
Davini, P., von Hardenberg, J., Corti, S., Christensen, H. M., Juricke, S., Subramanian, A., Watson, P. A. G., Weisheimer, A., and Palmer, T. N.: Climate SPHINX: evaluating the impact of resolution and stochastic physics parameterisations in climate simulations, Geosci. Model Dev. Discuss., doi:10.5194/gmd-2016-115, in review, 2016.