The Navy Earth System Prediction Capability: Overview and Future Developments

The Navy Earth System Predictability Capability (Navy ESPC) is a global coupled forecast system that consists of the NAVy Global Environmental Model (NAVGEM) atmosphere model, the HYbrid Coordinate Ocean Model (HYCOM) and the Community Ice CodE (CICE). This system has been developed to meet the U. S. Navy needs for high-resolution global environmental forecasts on timescales from days to months, and a unique aspect of the system is the eddy resolving ocean model at the ensemble and deterministic resolutions. Navy ESPC-E (ensemble) v1 (version 1), consisting of weekly 45-day 16-member ensemble forecasts, became operational in August 2020. Navy ESPC-E v1 products are used by the Joint Typhoon Warning Center for tropical cyclone genesis and the National Ice Center for resupply mission and exercise planning. Navy ESPC-E v2 (version 2) and Navy ESPC-D (deterministic) v2 systems are currently undergoing testing for operational transition. New capabilities and upgrades in version 2 include one-way coupling to the WAVEWATCH III wave model, an extension of the NAVGEM top from 72 to 110 km and improved representation of the middle atmosphere, the inclusion of arctic land-fast ice in CICE, increased NAVGEM horizontal resolution and inclusion of ocean tides in the ensemble configuration. Navy ESPC-D v2 performance is comparable or superior to the stand-alone systems for most (but not all) metrics. Future upgrades to Navy ESPC include improvements to the data assimilation and ensemble design, and eventual replacement of NAVGEM with the Navy’s next generation atmospheric model NEPTUNE (The Navy Environmental Prediction sysTem Using a Nonhydrostatic Engine).