Salinity and Stratification at the Sea Ice Edge (SASSIE): An oceanographic field campaign in the Beaufort Sea

Abstract

Abstract. As our planet warms, Arctic sea ice coverage continues to decline resulting in complex feedbacks with the climate system. The core objective of NASA’s Salinity and Stratification at the Sea Ice Edge (SASSIE) mission is to understand how ocean salinity and near-surface stratification affect upper ocean heat content, and thus sea ice freeze and melt. SASSIE specifically focuses on the formation of Arctic sea ice in autumn. The SASSIE field campaign in 2022 collected detailed observations of upper ocean properties and meteorology near the sea ice edge in the Beaufort Sea using ship-based and piloted and drifting assets. The observations collected during SASSIE include vertical profiles of stratification up to the sea surface, air-sea fluxes, and ancillary measurements that are being used to better understand the role of salinity in coupled Arctic air-sea-ice processes. This publication provides a detailed overview of the activities during the 2022 SASSIE campaign and presents the publicly available datasets generated by this mission, inducing an accompanying repository that highlights the numerical routines used to generate the figures shown in this manuscript.

Autumnal Equinox Shift in Arctic Surface Energy Budget: Beaufort‐Chukchi Seas Case Study

“…The vessel steered northward, heading toward the designated study area in the Beaufort Sea. On 8th September 2022, it arrived the marginal ice zone near 72°N, 150°W, marking the commencement of continuous shipboard air-sea measurements that lasted until 2nd October 2022 (Drushka et al, 2024). A chronology of the ship's movements and the time spent in each region is depicted in Figure 1, showing the ship's course through the Beaufort Sea, its transition across the Chukchi Sea, and the completion of its data collection near Cape Lisburne.…”

“…Given the low Arctic temperatures, which limit the moisture-holding capacity of the air (Andreas et al, 2002;Gettelman et al, 2006), a constant RH of 89% was assumed for the duration of the observation. The Q LH estimates derived from serve as the standard reference (Drushka et al, 2024). To assess potential uncertainties stemming from this assumption, two additional Q LH calculations were conducted.…”

“…Prominent among these field efforts are the Surface Heat Budget of the Arctic Ocean field experiment in the 1990s (Perovich et al, 1999;Uttal et al, 2002), and the more recent Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC) campaign, recognized as the most extensive Arctic drift campaign in the central Arctic to date (Cox et al, 2023;Shupe et al, 2022). Another significant recent initiative is NASA's Salinity and Stratification at the Sea Ice Edge (SASSIE) program (Drushka et al, 2024), conducted from 5th September to 2nd October 2022, in the Beaufort and Chukchi Seas (Figure 1). This program aimed to enhance our understanding of how salinity anomalies from summer ice melt affect the initiation of sea ice formation in early autumn.…”