The Consortium forof Ocean and Sea Ice Modelling in Australia (COSIMA): Where we've come from and where we are going

We will present an overview of the Consortium forof Ocean -and Sea Ice Modelling in Australia (COSIMA), including our ethical foundations, approaches to community building, and model development achievements and plans. COSIMA was formed to support the development of model configurations for the Australian community, with a focus on Southern Ocean science. COSIMA grew from foundational efforts to establish national partnerships that began in 2012 and received funding in 2016 that covers the salary of one research fellow and a part-time software engineer. From this modest funding base, COSIMA has transformed ocean-sea ice modelling in Australia, leveraging a community of >100 researchers to produce and freely distribute the ACCESS-OM2 model at three different resolutions. The ACCESS-OM2 model has been widely adopted in Australia, underpinning over 77 published papers and forming part of the ACCESS-CM2 and, ACCESS-CM2-025 climate models and OceanMAPS ocean forecasting system (Bluelink). However, ACCESS-OM2 is built on legacynow-obsolescent code (MOM5 and CICE5), so COSIMA and the ACCESS-NRI are building its successor, ACCESS-OM3, which will update Australia's modelling systems to keep abreast of (and better engage with) the leading edge of international model development. ACCESS-OM3 couples the WaveWatch 3 (WW3) surface wave model with the latest MOM6 and CICE6, which will enableing representation of ice-wave and ice-ocean interaction, floe size distribution, landfast ice and ice shelf cavity circulation, and provideing more efficient biogeochemistry and reduced numerical diffusion. Global configurations at resolutions up to 1/25° are planned, together with much higher-resolution regional configurations. 1° and 0.25°Lower-resolution global configurations (without WW3) have beenwill be coupled with UM-CABLE via NUOPC and willto form the ACCESS-CM3 and ACCESS-ESM3 climate models intended for Australia's CMIP7 submission. We will present initial results from test runs of global 1° and 0.25° configurations.