The NOAA Research Global-Nest Initiative was founded in 2022 as a Congressionally mandated project to develop new kilometer-scale global-nested and global-storm resolving models. Its principal goal was to improve prediction and understanding of extreme weather events, their impacts, and their role in the broader Earth system. To accomplish this task, several institutions worked towards enhancing capabilities in the GFDL SHiELD, an FV3-based global weather-to-subseasonal prediction system.
The primary deliverables of the first phase of this Initiative have been met. The global 6.5-km SHiELD provides real-time global extreme weather prediction, a NOAA first. A new version of the X-SHiELD Global-Storm-Resolving Model (GSRM) has been created and applied to multi-year integrations. Significant improvements to global-nested SHiELD, the Contiguous United States SHiELD (C-SHiELD) and the Tropical SHiELD (T-SHiELD), have been implemented and applied to a range of prediction problems. These models have all shown major scientific improvements, especially in the prediction of tropical cyclones, heavy precipitation, and severe convective storms, and have begun to be applied to extended-range prediction of severe weather outbreaks, machine learning applications, and atmospheric rivers. These models have also been submitted to a variety of testbeds and international comparisons, in particular SHiELD is the only US model participating in both Data Integration, Modeling, and Observations for Subseasonal-to-seasonal Impact Capabilities (DIMOSIC) and Weather and Precipitation – Model Intercomparison Project (WP-MIP).
The Global-Nest Initiative is already working to push into new areas. The AI-SHiELD emulator, powered by the Ai2 Climate Emulator (ACE), and the performance-portable Pace implementation in Python, show new technologies being integrated into the Initiative. A new Three‑Dimensional Turbulent Kinetic Energy (3D TKE) scheme in FV3 opens the doors to multi-nested large-eddy simulation. SHiELD is leveraging the powerful Flexible Modeling System (FMS) Coupler for integration into the famous GFDL coupled model suite for kilometer-scale atmosphere-ocean-wave coupling. New frontiers include compound drought-heatwave prediction, sub-kilometer extremes such as hurricane gusts and tornado vortices, coupling of explicit convection to large scales and external forcing, and subseasonal prediction of impactful weather events.
This webinar will conclude with prospects for future development and community involvement, as well as a demonstration of the major advance in tropical cyclone prediction achieved since the implementation of FV3 into the GFS in 2019, a huge success for the NOAA community.
Global-Nest Initiative home page: https://www.gfdl.noaa.gov/noaa-research-global-nest-initiative/
SHiELD: https://www.gfdl.noaa.gov/shield/
FV3: https://www.gfdl.noaa.gov/fv3/
