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Abstract The freshwater content of the Arctic Ocean has increased dramatically in the last two decades, particularly in the Beaufort Gyre. However, quantifying the sources of this change is an observational challenge and has historically been limited by methodological differences across studies. Here we derive observation‐based freshwater budgets from volume and mass budgets for the Arctic Ocean and the Beaufort Gyre from 2003 to 2020. Our budgets include all sources and sinks (river runoff, precipitation minus evaporation, land ice melt, sea ice export, sea ice melt, and ocean fluxes) as well as volume and mass storage terms measured by satellite. We find that Arctic freshwater changes are dominated by changes in the Beaufort Gyre, and we reconcile this with previous studies that argue for freshwater compensation between the Beaufort Gyre and the rest of the Arctic. We use inverse methods to close the volume and mass budgets within observational uncertainty and link the observed Arctic freshwater changes to the sources and sinks. Our budget analysis demonstrates that small changes to the ocean fluxes (smaller than we can measure) can account for all freshwater storage changes in the Arctic, highlighting the need for more careful accounting and detailed ocean observations in this rapidly changing environment.
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90 years of Arctic Ocean Exploration at the Woods Hole Oceanographic Institution
In 2020, the Woods Hole Oceanographic Institution (WHOI) celebrates 90 years of research, education, and exploration of the World Ocean. Since inception this has included Arctic studies. In fact, WHOI’s first technical report is on the oceanographic data obtained during the submarine “Nautilus” polar expedition in 1931. In 1951 and 1952, WHOI scientists supervised the collection of hydrographic data during the U.S. Navy SkiJump I & II expeditions utilizing ski-equipped aircraft landings in the Beaufort Sea, and inferred the Beaufort Gyre circulation cell and existence of a mid-Arctic ridge. Later classified studies, particularly concerning under-ice acoustics, were conducted by WHOI personnel from Navy and Air Force ice camps. With the advent of simple satellite communications and positioning, WHOI oceanographers began to deploy buoys on sea ice to obtain surface atmosphere, ice, and upper ocean time series data in the central Arctic beginning in 1987. Observations from these first systems were limited technologically to discrete depths and constrained by power considerations, satellite throughput, as well as high costs. As technologies improved, WHOI developed the drifting Ice-Tethered Profiler (ITP) to obtain vertically continuous upper ocean data several times per day in the ice-covered basins and telemeter the data back in near real time to the lab. Since the 1980s, WHOI scientists have also been involved in geological, biological, ecological and geochemical studies of Arctic waters, typically from expeditions utilizing icebreaking vessels, or air supported drifting platforms. Since the 2000s, WHOI has maintained oceanographic moorings on the Beaufort Shelf and in the deep Canada Basin, the latter an element of the Beaufort Gyre Observing System (BGOS). BGOS maintains oceanographic moorings via icebreaker, and conducts annual hydrographic and geochemical surveys each summer to document the Beaufort Gyre freshwater reservoir that has changed significantly since earlier investigations from the 1950s–1980s. With the experience and results demonstrated over the past decades for furthering Arctic research, WHOI scientists are well positioned to continue to explore and study the polar oceans in the decades ahead
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- PAR ID:
- 10205787
- Date Published:
- Journal Name:
- Journal of Oceanological Research
- Volume:
- 48
- Issue:
- 3
- ISSN:
- 1564-2291
- Page Range / eLocation ID:
- 164 to 198
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.29006/1564-2291.JOR-2020.48(3).10
