Facilitating the development of complex models with the Common Community Physics Package and its Single-Column Model
Authors: Bernardet Ligia , Firl Grant , Swales Dustin , Zhang Man , Kavulich Mike , Trahan Samuel , Li Weiwei , Dudhia Jimy , Ek Mike 
Published: February 2023

The Common Community Physics Package (CCPP) is a collection of atmospheric physical parameterizations and a framework that couples the physics for use in Earth system models. The CCPP Framework was developed by the U.S. Developmental Testbed Center (DTC) and is now an integral part of the Unified Forecast System (UFS). The UFS is a community-based, coupled, comprehensive Earth modeling system designed to support research and be the source system for NOAA&#8216;s multi-scale operational numerical weather prediction applications. The CCPP is also being used in the experimental U.S. Navy Environmental Prediction sysTem Utilizing the NUMA&#160; corE (NEPTUNE, which employs a modified version of the Non-hydrostatic United Model for the Atmosphere dynamical core) and is currently being integrated into the Community Atmosphere Model (CAM) utilized in the National Center for Atmospheric Research (NCAR) Community Earth System Model (CESM).A primary goal for this effort is to facilitate research and development of physical parameterizations, while simultaneously offering capabilities for use in operational models. The CCPP Framework supports configurations ranging from process studies to operational numerical weather prediction as it enables host models to assemble the parameterizations in flexible suites. Framework capabilities include flexibility with respect to the order in which schemes are called, ability to group parameterizations for calls in different parts of the host model, and ability to call some parameterizations more often than others. Furthermore, the CCPP is distributed with a single-column model (SCM) that can be used to test innovations,&#160; conduct hierarchical studies in which physics and dynamics are decoupled, and isolate processes to more easily identify issues associated with systematic model biases. The CCPP SCM can be driven using files in the DEPHY format (an internationally agreed-upon format for inputs and outputs of SCMs). This opens doors for collaborations using multiple initial and forcing datasets based on observational field campaigns. The CCPP SCM is also being updated to be forced by the UFS.The CCPP v6.0.0 public release includes 23 primary parameterizations (and six supported suites), representing a wide range of meteorological and land-surface processes. Experimental versions of the CCPP also contain chemical schemes, making it possible to represent processes in which chemistry and meteorology are tightly coupled.The CCPP is developed as open-source code and has received contributions from the wide community in the form of new schemes and innovations within existing schemes. In this presentation, we will provide an update on CCPP development and plans, as well as review existing resources for users and developers, such as the public releases, documentation, tutorial, and support mechanism. We will also provide information about the upcoming CCPP Visioning Workshop, indeed to be a forum for current and future CCPP users to learn about its capabilities and discuss requirements for new development.&#160;