Domain Decomposition in space-time of 4D-VAR Data Assimilation problem: a case study on the ROMS software

TL;DR

This paper explores domain decomposition techniques for 4D-VAR data assimilation using ROMS software, focusing on mathematical formulation and MPI-based implementation to improve computational efficiency.

Contribution

It introduces a novel domain decomposition approach for 4D-VAR data assimilation within ROMS, detailing both mathematical and software implementation aspects.

Findings

Effective domain decomposition reduces computational load.

MPI-based implementation enhances scalability and performance.

Framework applicable to large-scale ocean modeling problems.

Abstract

Domain Decomposition of 4D-VAR Data Assimilation (DD-4DVAR) is made up of decomposition of the spate-time domain, solution of reduced forecast model and minimization of local 4D-VAR functionals. Relying on the existing software implementation of ROMS software, we describe main components of DD-4D VAR DA method, highlighting the topics that we will should address both on the mathematical problem underlying ROMS and the MPI-based code implementation of the ROMS-IS4DVAR formulation.