The National Computational Infrastructure is a key part of Australia's climate modelling efforts. The CSIRO is using the supercomputing capability available at NCI to lead the development of the ACCESS climate model, in conjunction with the Bureau of Meteorology and the ARC Centre of Excellence for Climate System Science (ARCCSS).

ACCESS, the Australian Community Climate and Earth-System Simulator, couples together models of the atmosphere, oceans, land and sea ice to understand the behaviour of the Earth system as a whole. Recently, the team at CSIRO has added a carbon cycle model to ACCESS, producing an even more realistic representation of the interactions taking place within the climate system worldwide.

Running these models is a hugely data intensive process that cannot happen anywhere other than at NCI. By providing highly parallel computing infrastructure to the researchers, NCI makes this kind of large scale modelling possible. Lead Chief Investigator Dr Tony Hirst says that "All the ACCESS climate modelling is done on NCI."

The ACCESS model gives Australia an important role in international climate change planning. CSIRO and the ARCCSS produced simulations for the Intergovernmental Panel on Climate Change's Fifth Assessment Report in 2013, all of which were done on NCI. Dr Hirst says "We did 3700 years of simulation in total. It's important to do several simulations for each of the CO­­­2 emissions scenarios in order to separate the underlying trend from the variability."

The data from the simulations has now been connected to a worldwide network of Earth data, the Earth Systems Grid, through a dedicated NCI node. Researchers around the world can easily get access to the data and download the model output. This data has now been used in around 250 scientific papers in the last 2 years alone.

The partnership between NCI and CSIRO remains vital to Australia's climate modelling capability. As Dr Hirst says "We see ourselves as doing all our work on NCI going forward. Without exception, there is no other facility in Australia that allows us to work in the climate space in this way."

*Dr Tony Hirst has been working at the Bureau of Meteorology since July 2016.