Lasting impact of winds on Arctic sea ice through the ocean's memory

Abstract

Abstract. In this paper we studied the impact of winds on Arctic sea ice through the ocean's memory by using numerical simulations. We found that the changes in halosteric height induced by wind perturbations can significantly affect the Arctic sea ice drift, thickness, concentration and deformation rates regionally even years after the wind perturbations. Changes in the Arctic liquid freshwater content and thus in halosteric height can cause changes in the sea surface height and surface geostrophic currents, which further enforce a lasting and strong impact on sea ice. The changes in both sea surface height gradient force (due to changes in sea surface height) and ice–ocean stress (due to changes in surface geostrophic currents) are found to be important in determining the overall ocean effects. The revealed ocean effects are mainly associated with changes in sea ice dynamics, not thermodynamics. Depending on the preceding atmospheric mode driving the ocean, the ocean's memory of the wind forcing can lead to changes in Arctic sea ice characteristics with very different spatial patterns. We obtained these spatial patterns associated with Arctic Oscillation, Arctic Dipole Anomaly and Beaufort High modes through dedicated numerical simulations. The dynamical impact of the ocean has strong seasonal variations, stronger in summer and weaker in winter and spring. This implies that declining trends of Arctic sea ice will very possibly allow a stronger ocean impact on the sea ice in a warming climate.

A Synthesis of the Upper Arctic Ocean Circulation During 2000–2019: Understanding the Roles of Wind Forcing and Sea Ice Decline

“…We note that the applied wind perturbations also lead to changes in sea ice thickness (that is, solid freshwater), sea ice concentration and drift (Figure S4). Both the ocean circulation and sea ice state respond to the wind perturbations as a coupled system with interaction between them, which is investigated in Wang et al (2021a) and not the focus of the current study. The results shown in this section will serve as a reference when understanding the role of winds in impacting the upper Arctic Ocean changes during 2000-2019 in the next section.…”

Sea Ice Rheology Experiment (SIREx): 1. Scaling and Statistical Properties of Sea‐Ice Deformation Fields

“…We also note that the role of the ocean in setting the observed and simulated deformation statistics has not yet been fully evaluated, even though eddies (e.g., Cassianides et al, 2021), tides (e.g., Heil et al, 2008, and ocean circulation patterns (e.g., Wang et al, 2021;Willmes & Heinemann, 2016) are known to impact sea-ice dynamics. A major difficulty in assessing the role of varying ocean model complexity in coupled ice-ocean simulations resides in the fact that the spatial (and temporal) resolution of the sea-ice model is closely tied, if not the same, to that of the ocean model.…”

Surface and Interior Dynamics of Arctic Seas Using Surface Quasi-Geostrophic Approach

“…The East Siberian Sea (see Figure 2e,f) is characterized by a more stable, highly stratified water column throughout the year in the reanalysis data, with a less dense layer on the surface (22.8-23.8 kg/m 3 ), associated with cold and low-salinity waters, a pronounced pycnocline, and the denser Atlantic water (higher-salinity), with densities higher than 27.6 kg/m 3 below 150-200 m [4]. Riverine discharge has a great influence on the East Siberian Sea, and we would expect the density and stratification profiles to present a stronger seasonal variability than the reanalysis data reproduce, as the river discharge and advection processes are seasonal.…”

“…Changes in the hydrography of the upper Arctic Ocean, a hotspot for climate change, have been observed in recent observational and modeling studies. In particular, an increase in its liquid freshwater content, shifts in frontal locations and ocean currents, such as the intensification of the anticyclonic circulation in the Beaufort Gyre, or the shift of the transpolar drift have been described in the last decade [1][2][3][4]. An increase in the summer geostrophic currents of the Beaufort Gyre was linked to sea ice melt in the Beaufort Sea throughout the 2000s [5], evidencing the effects of climate change in high-latitude ocean dynamics.…”

“…Apart from the influence of AW transported from the Nordic Seas, the upper Arctic Ocean is largely influenced by the transport and transformation of water masses happening in the East Siberian Seas (ESS) [4], where the Arctic halocline water is partly produced [18]. The ESS is characterized by a buoyancy-driven eastward-flowing boundary current, which transports low-salinity and low-temperature waters from great Russian river discharges.…”