Profiling Floats for Sustained Arctic Observing
Abstract
The distribution of heat and freshwater within the Arctic Ocean play critical roles in modulating sea ice evolution, the Arctic ener,gy balance and the Arctic s impact on global climate (e.g. Prowse et al., 2015; Carmack et al., 2016). The Arctic serves as a freshw,ater source and heat sink for global ocean circulation. Freshwater enters through riverine inflow, excess precipitation and Bering S,trait inflow, and exits the Arctic through the Canadian Arctic Archipelago and Fram Fram Strait, flowing southward into sensitive de,ep water formation regions in the subpolar North Atlantic. Freshwater inputs also contribute to the formation of a shallow, cold hal,ocline, which inhibits mixing, insulating sea ice from heat stored in warmer layers below (e.g. Aagaard and Coachman, 1975). Atlanti,c waters that enter through Fram Strait and circulate throughout the Arctic provide the largest oceanic heat source. In the western,Arctic, relatively warm Pacific waters that enter through Bering Strait provide a second, shallower reservoir. Solar warming of the,surface layer and subsequent capping by fresher, colder waters produced by sea ice melt produce a third, shallowest layer, commonly,referred to as the Near-Surface Temperature Maximum (NSTM, e.g., McPhee et al., 1998; Perovich et al., 2008; Jackson el al. 2010). T,he distribution of stored subsurface heat and the associated stratification that modulates its vertical exchange govern the impact o,f these reservoirs on sea ice evolution. Seasonal, interannual and interdecadal variability in large-scale atmospheric forcing patte,rns drive circulation within the Arctic Ocean that redistributes freshwater and heat between basins. The Beaufort Gyre offers a prom,inent example, where shifts between anticyclonic and cyclonic atmospheric regimes cause the basin to shift from sequestering to rele,asing freshwater (Proshutinsky and Johnson, 1997), with significant impacts on upper ocean structure and freshwater outflows at the,CAA and Fram Straitgateways. Broad, sustained measurements are needed to quantify changing heat and freshwater distributions within,the Arctic Ocean interior and to understand the processes that govern their evolution.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 01, 2022
- Source ID
- N000142212347
Entities
People
- Craig Lee
Organizations
- Office of Naval Research
- United States Navy
- University of Washington