Adaptation of NEMO-LIM3 model for multigrid high resolution Arctic simulation

TL;DR

This paper presents a modified NEMO-LIM3 model with a multigrid setup for high-resolution Arctic ocean and sea ice simulations, improving flexibility and computational efficiency for regional risk assessment.

Contribution

The authors adapted NEMO-LIM3 for multigrid high-resolution Arctic modeling, reducing computational costs and enhancing simulation accuracy and flexibility.

Findings

Multigrid setup with 14 km and 5 km resolutions implemented.

Modified boundary-condition schemes for better grid interaction.

Ice-restoring scheme reduces spin-up time.

Abstract

High-resolution regional hindcasting of ocean and sea ice plays an important role in the assessment of shipping and operational risks in the Arctic Ocean. The ice-ocean model NEMO-LIM3 was modified to improve its simulation quality for appropriate spatio-temporal resolutions. A multigrid model setup with connected coarse- (14 km) and fine-resolution (5 km) model configurations was devised. These two configurations were implemented and run separately. The resulting computational cost was lower when compared to that of the built-in AGRIF nesting system. Ice and tracer boundary-condition schemes were modified to achieve the correct interaction between coarse- and fine grids through a long ice-covered open boundary. An ice-restoring scheme was implemented to reduce spin-up time. The NEMO-LIM3 configuration described in this article provides more flexible and customisable tools for high-resolution regional Arctic simulations.