Development of a Met Office NERC cloud model (MONC)

Very high resolution (~10 to 50 m) modelling of clouds, precipitation and cloud feedbacks is one of the tools that is used very effectively to further our understanding of the interactions of aerosol, clouds and radiation processes.

Within the UK one tool that is regularly used to conduct such research is the Met Office Large Eddy Model (LEM). The LEM and data generated by the LEM has been fundamental in the development and testing of the core functionalities in UK's main weather forecasting software, the Unified Mode (UM). As well as having a direct impact on the further development of the UM, over the past two decades the LEM has been regularly used by the Met Office and NERC scientists to conduct fundamental research into turbulence, clouds, convection and radiation.

The aim of this project is to use the LEM as a basis for the creation a Met Office/NERC cloud model (MONC). The development of MONC will address any shortcomings of the LEM, as well as upgrade and modernise its current structure with a view to enabling it on modern supercomputers.

The development of the Met Office NERC cloud (MONC) model will result in a very high resolution (~2 to 50 meters), flexible and portable cloud modeling framework. It will supported and administered through collaboration between the National Centre for Atmospheric Science (NCAS), and the UK Met Office. MONC will be developed from the UK Met Office LEM, which over the past two decades has been a very important tool for fundamental research and parametrisation development in cloud microphysics, turbulence and aerosol-cloud interactions within the UK. The development of MONC will ensure that this tool is maintained and enhanced for the NERC atmospheric science community. The new model will be designed in such a way so that it will capitalise on future enhancements in massively parallel processing (MPP) architectures, which will benefit all present and future Met Office and NERC users. More specifically the code architecture of MONC will enable very high resolution modelling of important atmospheric science problems e.g. high resolution (~10s of metres) large domain convection research or high resolution (~1s metres) stable boundary layer research, which with present LEM could not be tackled. This development will benefit parametrisation development within the NERC community and the Met Office, by providing a modern parallel numerical model, that is easy to set-up, modify and use and is portable across parallel systems in the UK. There is already significant interest within NCAS for the development of such a model. Th MONC model will also be an important tool for testing atmospheric dispersion problems and assumptions in parametrisations, and hence it will benefit the air quality and air dispersion communities in the UK. In addition to the modelling community, the development of the user friendly MONC model, will be of benefit to the observational community in that it will provide a system that can be easily used by observational scientists to test theories and compare with data. Thus, the MONC model should enhance pull-through of science from the atmospheric observational community. Finally, and importantly, the development of MONC will directly enable more effective collaboration between the Met Office and NERC by the development and a Met Office-NERC system. It will also indirectly enable collaboration by harmonising the MONC systems with the UM systems, where possible. Where applicable this will make the pull-through of NERC science to the Met Office UM more efficient.