How The Earth System Prediction Suite Contributes To A Coordinated U.S. S2s Research and Prediction Capability

Abstract

In order to extend predictions from weather to S2S timescales, atmospheric forecast models are often coupled to models of physical domains with slower dynamical processes, such as ocean and sea ice. The major patterns that affect S2S predictions, including ENSO, are created through such interactions. The need for model coupling for S2S prediction, and the distributed nature of model development across U.S. agencies, make standards for component interfaces important for S2S community building, coordination, and R2X. These standards minimize the effort required to build systems with components from multiple centers. The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. models and model components that span weather to climate timescales. They are being instrumented to conform to interoperability conventions, documented in a consistent manner, and made available either under open-source terms or to credentialed users. The ESPS represents a culmination of efforts to create a common Earth system model architecture, and the advent of increasingly coordinated model development activities in the United States. ESPS component interfaces are based on the Earth System Modeling Framework (ESMF), community-developed software for building and coupling models, and the National Unified Operational Prediction Capability (NUOPC) Layer, a set of ESMF-based component templates and interoperability conventions. This shared infrastructure simplifies the process of model coupling by guaranteeing that components conform to a set of technical and semantic behaviors. The ESPS encourages distributed, multiagency development of coupled modeling systems; controlled experimentation and testing; and exploration of novel model configurations, such as those motivated by research involving managed and interactive ensembles. The National Earth System Prediction Capability (NESPC) partner agencies are developing major modeling systems and components as part of the ESPS. Components and models in the ESPS include the Navy Global Environmental Model (NAVGEM), Hybrid Coordinate Ocean Model (HYCOM), and Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS); the NOAA Environmental Modeling System (NEMS) and Modular Ocean Model (MOM); the NSF Community Earth System Model (CESM); and the Goddard Earth Observing System Model, version 5 (GEOS-5). The standard interfaces in the ESPS enable its atmosphere, ocean, sea ice, wave, and other components to be run without change in multiple modeling systems. For example, the same ESPS version of HYCOM runs within Navy, NSF, and NOAA coupled modeling systems. In this way the ESPS and its underlying standards begin to transform the S2S modeling community from one in which multiple modeling centers strive to understand each other’s efforts, to one in which each agency can leverage resources across the nation.