The role of the cryosphere in source-to-sink systems

Jaeger, John; Koppes, Michèle

doi:10.1016/j.earscirev.2015.09.011

Cited by 57 publications

(50 citation statements)

References 445 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This does not mean that the sedimentary C in sea lochs is invulnerable, but rather that it is buffered from the immediate effects of chemical, biological and physical environmental change during interglacial periods. Over longer time frames it is known that these sedimentary stores are scoured by glacial advances, resulting in the material being transported to the adjacent shelf and slope (Jaeger and Koppes, 2016). Further investigation is required to better understand the processes governing the transfer of material to the shelf and what impact this has on the quality of OC in coastal sediment stores (Smith et al, 2015).…”

Section: Discussion: a New Sedimentary C Inventory For Scottish Coastmentioning

confidence: 99%

Substantial stores of sedimentary carbon held in mid-latitude fjords

et al. 2016

View full text Add to dashboard Cite

Quantifying marine sedimentary carbon stocks is key to improving our understanding of long-term storage of carbon in the coastal ocean and to further constraining the global carbon cycle. Here we present a methodological approach which combines seismic geophysics and geochemical measurements to quantitatively estimate the total stock of carbon held within marine sediment. Through the application of this methodology to Loch Sunart, a fjord on the west coast of Scotland, we have generated the first full sedimentary carbon inventory for a fjordic system. The sediments of Loch Sunart hold 26.9 ± 0.5 Mt of carbon split between 11.5 ± 0.2 and 15.0 ± 0.4 Mt of organic and inorganic carbon respectively. These new quantitative estimates of carbon stored in coastal sediments are significantly higher than previous estimates. Through an area-normalised comparison to adjacent Scottish peatland carbon stocks, we have determined that these mid-latitude fjords are significantly more effective as carbon stores than their terrestrial counterparts. This initial work supports the concept that fjords are important environments for the burial and long-term storage of carbon and therefore should be considered and treated as unique environments within the global carbon cycle.

show abstract

Section: Discussion: a New Sedimentary C Inventory For Scottish Coastmentioning

confidence: 99%

Substantial stores of sedimentary carbon held in mid-latitude fjords

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Reduced glacial erosive power occurs in cold to polythermal glaciers, slower flowing and small glaciers, in mountain ranges that have been recently glaciated, at low/ reverse bed slopes or overdeepenings, and in glacier systems with either very little basal debris or underlain by a till layer of substantial thickness (Hooke, 1991;Alley and others, 1997;Flowers and others, 2011;Jaeger and Koppes, 2016). Several of these are indicative of reduced subglacial drainage, which prevents flushing of sediments necessary to expose bedrock to erosion by ice (Hooke, 1991;Alley and others, 1997;Swift and others, 2002), and leads to weak subglacial water pressure fluctuations reducing sliding (Iken, 1981;Herman and others, 2011).…”

Section: Under What Conditions May Tributary/trunk Interaction Be Conmentioning

confidence: 99%

Flow and structure in a dendritic glacier with bedrock steps

2017

View full text Add to dashboard Cite

ABSTRACT. We analyse ice flow and structural glaciology of Shackleton Glacier, a dendritic glacier with multiple icefalls in the Canadian Rockies. A major tributary-trunk junction allows us to investigate the potential of tributaries to alter trunk flow and structure, and the formation of bedrock steps at confluences. Multi-year velocity-stake data and structural glaciology up-glacier from the junction were assimilated with glacier-wide velocity derived from Radarsat-2 speckle tracking. Maximum flow speeds are 65 m a −1 in the trunk and 175 m a −1 in icefalls. Field and remote-sensing velocities are in good agreement, except where velocity gradients are high. Although compression occurs in the trunk up-glacier of the tributary entrance, glacier flux is steady state because flow speed increases at the junction due to the funnelling of trunk ice towards an icefall related to a bedrock step. Drawing on a published erosion model, we relate the heights of the step and the hanging valley to the relative fluxes of the tributary and trunk. It is the first time that an extant glacier is used to test and support such model. Our study elucidates the inherent complexity of tributary/trunk interactions and provides a conceptual model for trunk flow restriction by a tributary in surge-type glaciers.

show abstract

“…Erosion by glaciers and ice sheets over multiple glacial cycles is responsible for producing diverse landscapes, generating and reducing relief, perturbing geochemical processes, and thereby contributing to climate oscillations during the Quaternary Period (Montgomery, 2002;Brook et al, 2006;Koppes and Montgomery, 2009;Brocklehurst, 2010;Jaeger and Koppes, 2016;Egholm et al, 2017;Torres et al, 2017). Erosion plays a dominant role in landscape evolution, so placing constraints on glacial erosion depths and patterns will enable a better understanding of the relative importance of the different drivers of these erosional processes (Hallet et al, 1996;Koppes et al, 2015;Herman et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

Ice cap erosion patterns from bedrock ¹⁰Be and ²⁶Al, southeastern Tibetan Plateau

Stroeven

Harbor

et al. 2018

Earth Surf Processes Landf

View full text Add to dashboard Cite

Quantifying glacial erosion contributes to our understanding of landscape evolution and topographic relief production in high altitude and high latitude areas. Combining in situ 10Be and 26Al analysis of bedrock, boulder, and river sand samples, geomorphological mapping, and field investigations, we examine glacial erosion patterns of former ice caps in the Shaluli Shan of the southeastern Tibetan Plateau. The general landform pattern shows a zonal pattern of landscape modification produced by ice caps of up to 4000 km2 during pre‐LGM (Last Glacial Maximum) glaciations, while the dating results and landforms on the plateau surface imply that the LGM ice cap further modified the scoured terrain into different zones. Modeled glacial erosion depth of 0–0.38 m per 100 ka bedrock sample located close to the western margin of the LGM ice cap, indicates limited erosion prior to LGM and Late Glacial moraine deposition. A strong erosion zone exists proximal to the LGM ice cap marginal zone, indicated by modeled glacial erosion depth >2.23 m per 100 ka from bedrock samples. Modeled glacial erosion depths of 0–1.77 m per 100 ka from samples collected along the edge of a central upland, confirm the presence of a zone of intermediate erosion in‐between the central upland and the strong erosion zone. Significant nuclide inheritance in river sand samples from basins on the scoured plateau surface also indicate restricted glacial erosion during the last glaciation. Our study, for the first time, shows clear evidence for preservation of glacial landforms formed during previous glaciations under non‐erosive ice on the Tibetan Plateau. As patterns of glacial erosion intensity are largely driven by the basal thermal regime, our results confirm earlier inferences from geomorphology for a concentric basal thermal pattern for the Haizishan ice cap during the LGM. © 2018 John Wiley & Sons, Ltd.

show abstract

The role of the cryosphere in source-to-sink systems

Abstract: 2016-11-02T18:49:00

Cited by 57 publications

References 445 publications

Substantial stores of sedimentary carbon held in mid-latitude fjords

Substantial stores of sedimentary carbon held in mid-latitude fjords

Flow and structure in a dendritic glacier with bedrock steps

Ice cap erosion patterns from bedrock ¹⁰Be and ²⁶Al, southeastern Tibetan Plateau

Contact Info

Product

Resources

About

The role of the cryosphere in source-to-sink systems

Abstract: 2016-11-02T18:49:00

Cited by 57 publications

References 445 publications

Substantial stores of sedimentary carbon held in mid-latitude fjords

Substantial stores of sedimentary carbon held in mid-latitude fjords

Flow and structure in a dendritic glacier with bedrock steps

Ice cap erosion patterns from bedrock 10Be and 26Al, southeastern Tibetan Plateau

Contact Info

Product

Resources

About

Ice cap erosion patterns from bedrock ¹⁰Be and ²⁶Al, southeastern Tibetan Plateau