Subinertial Variability in Four Southeast Greenland Fjords in Realistic Numerical Simulations

Gelderloos, Renske; Haine, Thomas W. N.; Almansi, Mattia

doi:10.1029/2022jc018820

Cited by 4 publications

(9 citation statements)

References 79 publications

(130 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During the winter, even though CTWs can drive a rapid fluctuation, they might contribute only modestly to mixing. Low dissipation would be consistent with modeling studies focusing on CTWs on Greenland's shelf and fjords (Gelderloos et al., 2021, 2022). During the summer, when the circulation is plume‐dominated, the weak mixing indicates that the outgoing exchange is primarily set by the subglacial discharge plume parameterization.…”

Section: Discussionsupporting

confidence: 86%

Relative Roles of Plume and Coastal Forcing on Exchange Flow Variability of a Glacial Fjord

Sanchez,

Straneo,

Hughes

et al. 2024

JGR Oceans

View full text Add to dashboard Cite

Glacial fjord circulation determines the import of oceanic heat to the Greenland Ice Sheet and the export of ice sheet meltwater to the ocean. However, limited observations and the presence of both glacial and coastal forcing—such as coastal‐trapped waves—make uncovering the physical mechanisms controlling fjord‐shelf exchange difficult. Here we use multi‐year, high‐resolution, realistically forced numerical simulations of Sermilik Fjord in southeast Greenland to evaluate the exchange flow. We compare models, with and without a plume, to differentiate between the exchange flow driven by shelf variability and that driven by subglacial discharge. We use the Total Exchange Flow framework to quantify the exchange volume transports. We find that a decline in offshore wind stress from January through July drives a seasonal reversal in the exchange flow increasing the presence of warm Atlantic Water at depth. We also find that including glacial plumes doubles the exchange flow in the summer. Our results show that the plume‐driven circulation is more effective at renewal with a flushing time 1/3 that of the shelf‐driven circulation near the fjord head.

show abstract

Section: Discussionsupporting

confidence: 86%

Relative Roles of Plume and Coastal Forcing on Exchange Flow Variability of a Glacial Fjord

Sanchez,

Straneo,

Hughes

et al. 2024

JGR Oceans

View full text Add to dashboard Cite

show abstract

“…During the winter, even though CTWs can drive a rapid fluctuation, they might contribute only modestly to mixing. Low dissipation would be consistent with modeling studies focusing on CTWs on Greenland's shelf and fjords (Gelderloos et al, 2021(Gelderloos et al, , 2022. During the summer, when the circulation is plume-dominated, the weak mixing indicates that the outgoing flux is primarily set by the subglacial discharge plume parameterization.…”

Section: Fjord Mixingsupporting

confidence: 83%

“…Previous simulations of Sermilik Fjord (or idealized versions) have focused on coastaltrapped waves (Jackson et al, 2018;Gelderloos et al, 2022), subglacial discharge plumes (Sciascia et al, 2013), the impact of icebergs (Davison et al, 2020) and standing eddies (Zhao, Stewart, McWilliams, Fenty, & Rignot, 2022). However none of these studies involved the use of a full 3-dimensional model with realistic bathymetry and time-varying realistic forcing.…”

Section: Background On Sermilik Fjord Systemmentioning

confidence: 99%

See 1 more Smart Citation

Relative roles of plume and coastal forcing on exchange flow variability of a glacial fjord

Sanchez,

Straneo,

Hughes

et al. 2023

Preprint

View full text Add to dashboard Cite

Glacial fjord circulation determines the import of oceanic heat to the Greenland Ice Sheet and the export of ice sheet meltwater to the ocean. However, limited observations and the presence of both glacial and coastal forcing - such as coastal-trapped waves - make uncovering the physical mechanisms controlling fjord-shelf exchange difficult. Here we use multi-year, high-resolution, realistically forced numerical simulations of Sermilik Fjord in southeast Greenland to evaluate the exchange flow. We compare models, with and without a plume, to differentiate between the exchange flow driven by shelf variability and that driven by subglacial discharge. We use the Total Exchange Flow framework to quantify the exchange volume fluxes. We find that a decline in offshore wind stress from January through July drives a seasonal reversal in the exchange flow increasing the presence of warm Atlantic Water at depth, that the exchange flux in the summer doubles with the inclusion of glacial plumes, and that the plume-driven circulation is more effective at renewal with a flushing time 1/3 that of the shelf-driven circulation near the fjord head.

show abstract

“…But the flow is not steady in time. Recent examination of four East Greenland fjords, including two in SEG (Kangerdlugssuaq and Sermilik), found periodicity in current patterns in the range of 2-4 days for Kangerdlugssuaq, plus a broad peak around 10 days (Gelderloos et al, 2022). Thus, factors still not included in this study warrant examination and future synthesis.…”

Section: Solid Ice Dischargementioning

confidence: 85%

Characterizing Southeast Greenland fjord surface ice and freshwater flux to support biological applications

Moon,

Cohen,

Black

et al. 2024

Preprint

View full text Add to dashboard Cite

Abstract. Southeast Greenland (SEG) is characterized by complex morphology and environmental processes that create dynamic habitats for resident marine top predators. Active glaciers producing solid ice discharge, freshwater flux, offshore sea ice transport, and seasonal landfast ice formation all contribute to a variable, transient environment within SEG fjord systems. Here, we investigate a selection of physical processes in SEG to provide a regional characterization to reveal physical system processes and support biological research. SEG fjords exhibit high fjord-to-fjord variability regarding bathymetry, size, shape, and glacial setting, influencing some processes more than others. For example, the timing of offshore sea ice formation in fall near SEG fjords progresses temporally southward across latitudes while the timing of offshore sea ice disappearance is less dependent on latitude. Rates of annual freshwater flux into fjords, in contrast, are highly variable across SEG, with annual average input values ranging from ~1x108 m3 to ~1.25x1010 m3 (~0.1–12.5 Gt) for individual fjords. Similarly, rates of solid ice discharge in SEG fjords vary widely – in part due to the irregular distribution of active glaciers across the study area (60° N–70° N). Landfast sea ice, assessed for 8 focus fjords, is seasonal and has a spatial distribution highly dependent on individual fjord topography. Conversely, glacial ice is deposited into fjord systems year-round, with the spatial distribution of glacier-derived ice dependent on glacier termini location. As climate change continues to affect SEG, the evolution of these metrics will be individually variable in their response, and next steps should include moving from characterization to system projection. Due to projected regional ice sheet persistence that will continue to feed glacial ice into fjords, it is possible that SEG could remain a long-term (century to millennia scale) refugia location for polar bears and other ice-dependent species, demonstrating a need for continued research on the SEG physical environment.

show abstract

Subinertial Variability in Four Southeast Greenland Fjords in Realistic Numerical Simulations

Cited by 4 publications

References 79 publications

Relative Roles of Plume and Coastal Forcing on Exchange Flow Variability of a Glacial Fjord

Relative Roles of Plume and Coastal Forcing on Exchange Flow Variability of a Glacial Fjord

Relative roles of plume and coastal forcing on exchange flow variability of a glacial fjord

Characterizing Southeast Greenland fjord surface ice and freshwater flux to support biological applications

Contact Info

Product

Resources

About