Shortening the runtime using larger time steps for the simulation of marine ecosystem models

TL;DR

This study demonstrates that using larger time steps in marine ecosystem models can significantly reduce computational costs while maintaining acceptable accuracy in steady annual cycle simulations.

Contribution

It provides a systematic investigation showing that larger time steps can be used without compromising the accuracy of steady annual cycle solutions in biogeochemical models.

Findings

Larger time steps reduce simulation runtime.

Steady annual cycles remain accurate with bigger time steps.

Applicable across models of increasing complexity.

Abstract

The reduction of computational costs for marine ecosystem models is important for the investigation and detection of the relevant biogeochemical processes because such models are computationally expensive. In order to lower these computational costs by means of larger time steps we investigated the accuracy of steady annual cycles (i.e., an annual periodic solution) calculated with different time steps. We compared the accuracy for a hierarchy of biogeochemical models showing an increasing complexity and computed the steady annual cycles with offline simulations that are based on the transport matrix approach. For each of these biogeochemical models, we obtained practically the same solution even though larger time steps. This indicates that larger time steps shortened the runtime with an acceptable loss of accuracy.