August 20, 2020 | Published by |

by Claire Carouge
Although we are waiting on the official release of ACCESS-ESM1.5, it is time to highlight the part played by the CMS team in delivering this model to the community. First, we want to acknowledge the work done by the CSIRO’s ACCESS team in creating the model: coupling the different codes together, tuning the model and delivering the core simulations of CMIP6. The CMS involvement started quite late with the need to develop model configurations for several paleoclimate runs, including some contributions to PMIP4, the paleoclimate component of CMIP6.

When we received the model from the CSIRO, it was managed by a suite of shell scripts. Those scripts were used for the version 1.0 of ACCESS but they are difficult for both users and support to navigate. In order to improve on the usability and supportability of ACCESS-ESM1.5, we first decided to migrate it to the Payu workflow management system. The Payu system was first developed by the CMS team for managing the Modular Ocean Model (MOM) simulations. It allows users to learn how to use the model much more quickly and simplifies the handling of very long simulations. The management of the files needed and generated by the model is also simplified. Additionally, by using the same workflow system for several models (ACCESS-ESM1.5, MOM5 and other ocean models) researchers can migrate faster between those codes as needed. Finally, it facilitates the support to users by providing a well-known interface to the model and by handling version control of the model configurations and user’s modifications.

At the end of 2019, NCI upgraded their high-performance computer (HPC) to Gadi. Holger Wolff worked with the ACCESS-ESM team at CSIRO to port the model to the new HPC. It was also decided to develop a proper building system for the model. This will facilitate modifications to the source code of ACCESS-ESM and will decrease the amount of modelling support needed in those cases. Due to the porting to the new HPC, the processor decomposition has been revised and ACCESS-ESM is now about twice as fast for the same cost (~1 hour / model year for 1KSU).

Payu is now the official configuration and run tool for ACCESS-ESM. Currently, only the piControl, Last Interglacial and Mid-Holocene configurations are available. You can see instructions here. A configuration for the Last Millenium simulation in PMIP4 is being developed. Moreover, we are able to port other CMIP6 configurations to Payu on request.

Lastly, we would like to warn researchers that no version of ACCESS-CM 1 has been ported to Gadi. We strongly encourage researchers to upgrade to ACCESS-ESM1.5 or ACCESS-CM2. If you require ACCESS-CM 1 to be ported, please contact the CMS team to discuss your needs and potential solutions.

Precipitation datasets

Paola Petrelli and some researchers from the Extreme Rainfall research program have put together a new data collection for precipitation datasets. In addition to regrouping the datasets already present and adding new ones, work was undertaken to present the various datasets following comparable formats as much as possible. This data collection currently lives in the staging area for CLEX datasets but ultimately, we are working on delivering this collection from its own area at NCI. Information on the precipitation datasets we manage can be found on the CMS wiki.

CleF 1.0.1

Paola Petrelli and Scott Wales have delivered the version 1.0.1 of CleF.  This version uses a database redesigned by NCI. This new database fixes some previous mistakes or omissions and introduces some improvements. In addition to allowing some simplifications in the CleF code, this new database now allows CleF to search the ACCESS data published by NCI for CMIP6. The latest version of CleF can be used from the conda environments we manage at NCI.