The Common Community Physics Package (CCPP): Unifying Physics across NOAA and NCAR Models Using a Common Software Framework

Years of independent development work have led to largely incompatible model components among the different U.S. agencies. To facilitate the transition of innovations from the research community to operations, the Global Model Test Bed (GMTB) with staff at NOAA and NCAR has been tasked to develop a collection of physical parameterizations and a software framework, called the Common Community Physics Package (CCPP). Recently, an agreement was made between NOAA and NCAR to jointly develop the CCPP framework as part of their Unified Forecasting System (UFS) and System for Integrated Modeling of the Atmosphere (SIMA) programs. This places the CCPP in the heart of several of the U.S. flagship models as a single, standardized way to interface physics with models of the atmosphere (and other components of the Earth system), and lowers the costs for the development and maintenance of the CCPP framework.

In this contribution, we will provide a brief overview of the concept of the CCPP, present its technical design and the requirements for parameterizations to be considered as CCPP-compliant, and describe the integration of CCPP with the host model. We will report on the recent transition of the CCPP to the UFS authoritative code base for use at the National Weather Service, and on the roadmap for a future transition into operations. We will also touch upon the challenges in creating a flexible modeling framework while maintaining high computational performance, reliability and reproducibility for operational applications. We will further demonstrate how the joint development of the CCPP framework has benefited and will benefit both research and operations in the form of a revised metadata standard and an improved code generator and system integration.