A 4.5 km resolution Arctic Ocean simulation with the global multi-resolution model FESOM 1.4

Abstract

Abstract. In the framework of developing a global modeling system which can facilitate modeling studies on Arctic Ocean and high-to midlatitude linkage, we evaluate the Arctic Ocean simulated by the multi-resolution Finite Element Sea ice-Ocean Model (FESOM). To explore the value of using high horizontal resolution for Arctic Ocean modeling, we use two global meshes differing in the horizontal resolution only in the Arctic Ocean (24 km vs. 4.5 km). The high resolution significantly improves the model's representation of the Arctic Ocean. The most pronounced improvement is in the Arctic intermediate layer, in terms of both Atlantic Water (AW) mean state and variability. The deepening and thickening bias of the AW layer, a common issue found in coarse-resolution simulations, is significantly alleviated by using higher resolution. The topographic steering of the AW is stronger and the seasonal and interannual temperature variability along the ocean bottom topography is enhanced in the high-resolution simulation. The high resolution also improves the ocean surface circulation, mainly through a better representation of the narrow straits in the Canadian Arctic Archipelago (CAA). The representation of CAA throughflow not only influences the release of water masses through the other gateways but also the circulation pathways inside the Arctic Ocean. However, the mean state and variability of Arctic freshwater content and the variability of freshwater transport through the Arctic gateways appear not to be very sensitive to the increase in resolution employed here. By highlighting the issues that are independent of model resolution, we address that other efforts including the improvement of parameterizations are still required.

Arctic Sea Ice Decline Significantly Contributed to the Unprecedented Liquid Freshwater Accumulation in the Beaufort Gyre of the Arctic Ocean

“…Details of the latest stable model version are provided in Wang et al (2014) and Danilov et al (2015). The model has been applied in different Arctic Ocean studies (e.g., Wang et al, 2016Wang et al, , 2018. Only a brief description of the specific model configuration used in this work is given below.…”

The Relative Influence of Atmospheric and Oceanic Model Resolution on the Circulation of the North Atlantic Ocean in a Coupled Climate Model

“…Increasing ocean model resolution in ocean models has a critical impact on the role that eddies play in the ocean heat budget and in the dynamics of major frontal systems (see, e.g., Iovino et al, 2016;Von Storch et al, 2016). Enhanced resolution improves the representation of narrow boundary currents (e.g., Marzocchi et al, 2015;Sein et al, 2017;Wang et al, 2018) and the connectivity between ocean basins (e.g., Chang et al, 2009). Increases of resolution in atmosphere-only models have also beneficial impacts on many aspects of the large-scale circulation and lead to a more realistic simulation of regional climate and small-scale phenomena (Jung et al, 2012, andHaarsma et al, 2016, for a comprehensive review).…”

Improving the Upper‐Ocean Temperature in an Ocean Climate Model (FESOM 1.4): Shortwave Penetration Versus Mixing Induced by Nonbreaking Surface Waves

“…The Finite Element Sea ice‐Ocean Model (FESOM), unlike most of the unstructured‐mesh ocean models that are intended for coastal and regional applications, is the first mature global unstructured‐mesh ocean model that was developed mainly for the purpose of climate research (Danilov et al, ; Sidorenko et al, ; Timmermann et al, ; Q. Wang et al, ). It has been assessed for various applications (e.g., Scholz et al, ; Q. Wang et al, , ) and used as the ocean sea‐ice component of the coupled AWI climate model (Rackow et al, ; Sidorenko et al, ).…”