Development of a Nested 4-Dimensional Variational (N4D-Var) Data Assimilation Capability for the Regional Ocean Modeling System (ROMS)

Abstract

The Regional Ocean Modeling System (ROMS) is one of the most widely used ocean models, both nationally and internationally. ROMS capabilities include both one-way and two-way nesting on a variety of composite and mosaic grid configurations, and a sophisticated, state-ofthe- art 4-dimensional variational (4D-Var) data assimilation system. The objective of this project is to combine the nested capabilities of ROMS with the 4D-Var system (and the associated suite of 4D-Var tools), which will allow users to assimilate data seamlessly across nested model grids. Importantly, this will allow for the greater utility of observations from new rapid-sampling platforms, such as gliders and AUVs, and high resolution remote sensing platforms such as SWOT and SAR imagery, thereby allowing for the maximum information return from such observations when combined with data assimilation into very high resolution nested grids capable of resolving the sub-mesoscale circulation. This project will extend the current separate ROMS 4D-Var and nested modeling capabilities, and allow assimilation of ocean observations across multiple one-way and two-way nested grids. The project is of considerable significance because it will open the door to data assimilation atthe sub-mesoscale and in the littoral zone, and allow seamless data assimilation from the gyrescale (~ 1000 s km) to the small scales (~ 1km or less) that characterize the near-shore circulation. This capability will be unique within the ocean modeling community, and expand considerably DoD capabilities in the realm of ocean data assimilation, nowcasting, and forecasting across multiple scales.

Document Details

Document Type
DoD Grant Award
Publication Date
Sep 04, 2018
Source ID
N000141812816

Entities

People

  • Andrew Moore

Organizations

  • Office of Naval Research
  • United States Navy
  • University of California, Santa Cruz

Tags

Fields of Study

  • Environmental science

Readers

  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Research Science/Academic Research

Technology Areas

  • Autonomy