Chukchi Sea circulation and Bering Strait flow reversals from reprocessed satellite altimetry

While difficult accessibility leads to a lack of oceanographic in-situ measurements in the Arctic Ocean, and in particular in the Chukchi Sea, satellite altimetry provides precise information on the sea surface at different spatial and temporal scales and can be used for studies of current patterns. Here, we created a novel long-term altimetry-based observational dataset of sea level and ocean currents, processed with the implementation of the recent advanced algorithms and special techniques for the reliable detection of leads and the determination of sea surface heights in the sea-ice-covered ocean. The dataset allowed us to observe the general patterns and synoptic variability of regional sea level and geostrophic flow. In the analysis, the reversals of the northward flow through the Bering Strait were investigated and linked to the anomalously strong northeasterly wind events over the Chukchi Shelf. While this phenomenon was previously described in purely oceanographic studies, the satellite altimetry-based dataset made it possible to assess its development, forcing, and variability with a high temporal-spatial resolution (10d/8km) over 2013–2023. The response of the along-strait flow to anomalously strong along-strait northerly winds is strong during fall in the absence of sea ice and well-correlated during winter and spring during partial ice cover.