ACCESS-CM2 Aimed For CMIP6: overview, introduction, and preliminary results (ocean & Sea ice) Dave Bi, Peter Dobrohotoff, Arnold Sullivan Ocean and Coupled Modelling Team CSIRO O&A Aspendale, Vic 3195 COSIMA 2017 UNSW May 25, 2017

Overview: Features and History of ACCESS-CM2 New Versions of All Components: Atmosphere: N96 UM10.6/GA7.1 (85 levels, active aerosol) Land: CABLE2.x (currently Jules) Ocean: 1-deg MOM5 Sea ice: 1-deg CICE5 (multi-layer) Coupler: OASIS3-MCT (real parallel coupling) New Framework/Control System: Cylc-Rose (“easier” for general users) History 2014/15 started from ACCESS1.4 framework  Prototype version ACCESS-CM2 (with UM8.6/GA6) 2016 switched to Cylc-Rose  Beta version ACCESS-CM2 (with UM10.3/GA7) [really tough year for CSIRO] 2017 upgraded UM to UM10.6/GA7.1  Official version ACCESS-CM2 (after long waiting……) Various delays because of strong dependence on collaborators’ delivery, especially the UKMO UM development (GA6GA7GA7.1) and difficult CABLE-UM coupling…… Current Status Just started tuning (mainly ocean and sea ice) for “acceptable” present day climate simulation CMIP6 delivery depends on model performance and timing……

Rose/Cylc ACCESS-CM2 Development | Peter Dobrohotoff | Page 3

Rose/Cylc ACCESS-CM2 Development | Peter Dobrohotoff | Page 4

Rose/Cylc ACCESS-CM2 Development | Peter Dobrohotoff | Page 5

ACCESS-CM2 Atmosphere: UM 10.x N96 (~130 km) Ocean: MOM5, 1 deg Sea Ice: CICE5 Coupler: OASIS3-MCT Atmosphere Present Day Test Compute UM 10.3 + JULES, GA7 - aerosol climatologies 200 yr 532 cores > 4 sim yr / day UM 10.6 + JULES, GA7.1 - full aerosol scheme 100 yr 532 cores > 3 sim yr / day UM 10.6 + CABLE, GA7.1 - full aerosol scheme Next ACCESS-CM2 Development | Peter Dobrohotoff | Page 6

SST time series & SST Bias ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1 ACCESS-CM2 with GA7-MAM ACCESS-CM2 with GA7.1-MAM

SON: ENSO and IOD ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1 Presentation title | Presenter name | Page 8

GMOC ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

AMOC ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

ACC via Drakepassage Present day with GA7 & mom5

Sea ice extent climatology Observation Present day with GA7 & mom5 Present day with GA7.1 & mom5 Historical with GC3

Sea Ice Thickness

NH: Ice thickness (AMJ) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

SH: Ice thickness (JAS) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

NH: Ice thickness (JFM) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

SH: Ice thickness (JFM) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

Sea Ice Concentration

NH: Ice concentration (AMJ) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

SH: Ice concentration (JAS) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

NH: Ice concentration (JFM) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1

SH: Ice concentration (JFM) ACCESS-CM2 with GA7 ACCESS-CM2 with GA7.1