Modelling the Earth System. Understanding and predicting climate changes and fluctuations

Transcription

1 02/02/2014 Modelling the Earth System Understanding and predicting climate changes and fluctuations IPSL Climate Modelling Centre J-L Dufresne Comité de visite de l AERES à l IPSL, 3-4 février 2014

2 Presentation The IPSL Climate Modelling Centre (ICMC) ICMC started in At that time major climate groups were already existing Integration of the various scientific topics necessary to built and ESM, distributed among the different IPSL laboratories A multi-disciplinary approach of the climate system and a coherent study of past, current and future climate changes were adopted since the beginning About persons contribute to ICMC (LMD, LSCE, LOCEAN, LATMOS mainly) Organisation: a steering committee, 13 working groups, a board, a leader Location: in Jussieu and Gif-sur-Yvette, mainly Institut Pierre Simon Laplace Page 2 Page 2

3 Presentation The IPSL Climate Modelling Centre (ICMC) The main fields of interest are: Anthropogenic climate changes Paleoclimate Cloud feedbacks Climate-bieogeochemistry feedbacks Chemical composition Variability, predictability Institut Pierre Simon Laplace Page 3 Page 3

4 Development of the IPSL-CM climate model 1995: ICMC beginning 1997: first Atm-Ocean coupled run with the IPSL model 1997: PMIP1 simulations, small contribution to CMIP1 & : coupled climate-carbon simulation : contribution to CMIP3 (and IPCC AR4) with IPSL-CM : broad development of IPSL-CM4 IPSL-CM5: gather the various developments in a single, common model Institut Pierre Simon Laplace Page 4 Page 4

5 The IPSL-CM5 Earth System Model Institut Pierre Simon Laplace Page 5 Page 5 All models are developed at IPSL, except the coupler

6 The IPSL-CM models for CMIP5 Earth System Model IPSL-CM5A-LR Low Resolution atm: 3.75 x2 L39 oce: 2 L31 IPSL-CM5A-MR Medium Resolution atm: 2.5 x1.25 L39 oce: 2 L31 Same + New atmospheric parameterisations Cold pools PBL: thermal plumes and cloud scheme Institut Pierre Simon Laplace Page 6 Page 6 Triggering and closure of convection IPSL-CM5B-LR Low Resolution atm: 3.75 x2 L39 oce: 2 L31

7 latitude O 3 concentration (ppb) Ozone zonal mean Mean ozone near surface [Bekki et al. 2013, Dufresne et al. 2013] [Szopa et al., 2013] Aerosols in 2100 Radiative forcing (W.m -2 ) particulate organic matter Black Carbone Sulphates [Szopa et al., 2013]

8 Carbon sink (PgC/y) Carbon Emission (PgC/y) Atmospheric CO 2 (ppm) Permissible CO 2 emissions Historical RCP8.5 RCP6.0 RCP4.5 RCP Institut Pierre Simon Laplace Page 8 Page 8

9 Decadal predictability Can the initialisation of the ocean improve the climate predictability? Atlantic Meridional Overturning Circulation (AMOC) AMOC at 48 N Reconstructions Understand the processes at play over the last 60 years Focus on the North Atlantic and the meridional overturning circulation using IPSL-CM5A-LR Mt Agung eruption leads to an AMOC maximum 15 after Adding the SST anomalies increase the second maximum through NAO signature on the SST (cooling) and increase in convection a few years earlier Initialised Historical Control [Swingedouw et al. 2013] Institut Pierre Simon Laplace Page 9 Page

10 Data distribution and CMIP5 analysis Large ensemble of simulations, from paleoclimate to aquaplanets 180 simulations (+ decadal), years, 3 models, 800 variables Due to the lack of maturity of ESGF, we have to install the data nodes and to distribute the data ourselves. IPSL 20 papers on IPSL-CM5 model analysis in a special issue of Clim. Dynamics Down-load part of the CMIP5 data base on the IPSL data centre (Prodiguer-Ciclad) to facilitate multi-model analysis More than 20 additional papers already published based on multi-model analysis Institut Pierre Simon Laplace Page 10 Page 10

11 Last glacial maximum Paleoclimate study using a proxy simulator Institut Pierre Simon Laplace Page 11 Page 11

12 Paleoclimate study using a proxy simulator Last glacial maximum Dabundance [G.Ruber] (DMG PI) Dexport (DMG PI) IPSL-ESM + proxy simulators biomes foraminifera Institut Pierre Simon Laplace Page 12 Page 12 [Kageyama et al, C Dyn 2013]

13 Holocene - PI Holocene - PI Future - PI Past and future precipitation changes Mid-Holocene - preindustrial future (RCP8.5) mm/d Future - PI Institut Pierre Simon Laplace Page 13 Page 13 group 1 group 3 [Schmidt et al, 2013]

14 Normalized inter model standard deviation Climate sensitivity Cloud Feedbacks The spread of climate sensitivity is still mainly due to cloud feedbacks The response of low level clouds plays a dominant role in this spread Half of this spread may be explain by the strength of the mixing between the PBL and the free troposphere Inter-model spread of the climate feedbacks Climate sensitivity vs mixing strength in present-day climate [Vial, et al., 2013] cloud [Sherwood, et al., 2014 feedbacks Institut Pierre Simon Laplace Page 14 Page 14

15 IPSL contribution to CMIP5 CMIP5 experiments analysis The IPSL-CM5 model represents a major step in the development of parameterizations and in the coupling between physical and many biogeochemical processes The IPSL contribution to CMIP5 represents a qualitative step forward compared to CMIP3: large amount of model simulations, large diversities of experiments, many publications on IPSL-CM5 model analysis and on multi-model CMIP5 analysis The IPSL is an important actor of these international projects: choice of the experiments, comparison with observations, model documentation, tools for ESGF CMIP5 lessons: Major biases remains in most of the CMIP5 models, including IPSL-CM5 (small improvements between CMIP3 and CMIP5) Large spread in climate change estimate, even for basic quantities (generally small or no decrease between CMIP3 and CMIP5) Institut Pierre Simon Laplace Page 15 Page 15

16 Prospective: Better representation of processes Atmospheric parameterisations LES/CRM simulations, case study LMDZ in single column mode clouds same forcings D x= D y= 1km Large domain CRM simulations LMDZ in zoomed/nudged mode and/or with analysis restarts Diurnal cycle, coupling with surface Intermittent precipitation (stochastic triggering of convection) In collaboration with CNRM Institut Pierre Simon Laplace Page 16 Page 16 Organised convection Micro et macro-physique of clouds.

17 Ocean and Ice-sheets Increase of horizontal (1 and 0.25 ) and vertical (75 layers) resolution Diurnal cycle Physical parameterisations Mesh refining in key regions New sea-ice model In collaboration with Brest, Grenoble, UCL Prospective: Better representation of processes Fresh water flux due to icesheet melting Outbreak and transport of icebergs Ocean- Ice shelf interactions In collaboration with LGGE, Grenoble Institut Pierre Simon Laplace Page 17 Page 17

18 Prospective: Better representation of processes Climate-biogeochemistry interactions Ocean: Variable stoichiometry (Fe, Chl, C, Si, P, N) More plankton types, diatoms Link with marine resources Coupling with aerosols and chemistry In collaboration with LPO, Brest Land: New hydrology Nitrogen cycle Fires High latitudes (snow, permafrost ) Surface exchanges Forest and agriculture management Institut Pierre Simon Laplace Page 18 Page 18

19 Ocean: domain nesting Atmosphere: grid refinement Prospective: Refining spatial resolution Example of domains: Mediterranean Europe West Africa India China South Est Asia South America Antarctica Greenland Planed work: Automation of tools ESM (chemistry, aerosols ) Coupling with the ocean (West- Africa Gulf of Guinea, Arctic basin ) Institut Pierre Simon Laplace Page 19 Page 19

20 Number of simulated year/day DYNAMICO: new dynamical core, icosahedral Prospective: New dynamical core Bench for a low resolution model (96x96 L39) DYNAMICO Present: New transport schema Quasi-uniform mesh Energy conserving Participation to the ICOMEX project Collaborations with applied mathematic Collaboration with IIT Delhi (OP Sharma) Institut Pierre Simon Laplace Page 20 Page LMDZ 256 Number of cores degrees nb cores year/day ½ ¼ Bench with different resolutions Plans: Stretched grid Non hydrostatic In the IPSL-CM model Deep atmospheres (planets)

21 Prospective: Improvement of the modelling platform Facing Big Data era and Exascale challenges for Climate Sciences To ensure efficient and reliable execution of climate models on new computer architectures To develop a national platform capable of running large ensembles of simulations with a suite of models To handle the complex and voluminous datasets generated To facilitate the evaluation and validation of the models and the use of higher resolution models. ANR-project numerical methods CONVERGENCE( ) IPSL, CNRM, CERFACS IDRIS, MS Institut Pierre Simon Laplace Page 21 Page 21

22 Prospective: Contribution to CMIP6 Resolution and computer resources 1/ IPSLCM1/2 ( ) IPSLCM4 ( ) IPSLCM5 ( ) IPSLCM6 (2014- ) 0.5 CMIP6 Tests 1 CMIP3 PMIP2 CMIP5 PMIP3 Tests 2 4 CMIP2 PMIP1 Institut Pierre Simon Laplace Page 22 Page 22

23 Position, recognition Involvement in international programs or projects Very active in the WCRP (co-lead of WGCM, CFMIP, PMIP, C4MIP ), IGBP (PAGES), ENES Important contribution to CMIP5, PMIP3, CFMIP, C4MIP, ACCMIP, GeoMIP, LUCID, AEROCOM Active in the preparation of the IPCC AR5 (7 CLA, LA or RE) International working groups: ESGF European projects: IS-ENES, Metafore, Euclipse, Combine, Embrace National level: very active collaborations with Météo-France, Cerfacs, LGGE, LPO Institut Pierre Simon Laplace Page 23 Page 23

24 Conclusions Our Challenges To improve the representation of processes and the characteristics of the simulated climate To integrate the new dynamical core and to face the very high parallelism challenges To consolidate the model and data analysis platforms To face the new requirements that arises from the emergence of the climate services To pursue the analysis of climate changes and variability, with a focus on past versus future changes, complex versus simplified configurations, better understanding, use of observations Institut Pierre Simon Laplace Page 24 Page 24

25 Conclusions The support we are looking for: The recognition of the specificity of a climate modelling centre (work requiring close collaboration between many persons, with different interests in different domains of expertise) and the fragility introduced by too many and too complex structures, with possible opposite interests (IDEX, OSU ) The labelling of the IPSL-CM model and the data analysis platform, and the need of long term supports ICMC, as such, recognized as a direct partner of the national computer centers and infrastructures, with a need of dedicated and specific resources The possibility to promote scientific positions to fill a missing expertise that is not a priority for the laboratories Institut Pierre Simon Laplace Page 25 Page 25

26 Thank you for your attention Institut Pierre Simon Laplace Page 26 Page 26

27 Organisation of IPSL Climate Modelling Centre Head: J-L Dufresne; Board: J-L Dufresne; L. Bopp, MA Foujols, J. Mignot Steering Committee Modelling platform (IPSL-ESM) Arnaud Caubel (LSCE) - Marie-Alice Foujols (IPSL) Atmospheric and surface physics and dynamics (LMDZ) Frédéric Hourdin (LMD) - Laurent Fairhead (LMD) Ocean and sea ice physics and dynamics (NEMO-OPA,NEMO-LIM) C Ethé (IPSL) - Claire Lévy - Gurvan Madec (LOCEAN) Atmosphere and ocean interactions (IPSL-CM, different resolutions) Sébastien Masson (LOCEAN) - Olivier Marti (LSCE) Atmospheric chemistry and aerosols (INCA, INCA_aer, Reprobus) Anne Cozic (LSCE) - M. Marchand (LATMOS) Current and future climate changes Jean-Louis Dufresne(LMD) - Olivier Boucher (LMD) Paleoclimate and last millennium Pascale Braconnot - Masa Kageyama (LSCE) Near-term prediction (seasonal to decadal) Eric Guilyardi (LOCEAN) - Juliette Mignot (LOCEAN) Regional climates Robert Vautard (LSCE), Laurent Li (LMD) Biogeochemical cycles (NEMO-TOP-PISCES) Laurent Bopp (LSCE) - Patricia Cadule (IPSL) Continental processes (ORCHIDEE) Philippe Peylin (LSCE) - Josefine Ghattas (IPSL) Data Archive and Access Requirements Sébastien Denvil (IPSL) - Karim Ramage (IPSL) Evaluation of the models, present-day and future climate change analysis Sandrine Bony (LMD) - Patricia Cadule (IPSL) - Marion Marchand (LATMOS) - Juliette Mignot (LOCEAN) Jérôme Servonnat (LSCE)