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Full-Text Articles in Glaciology
Influence Of Sea Ice On Arctic Precipitation, Ben G. Kopec, Xiahong Feng, Fred A. Michel, Eric S. Posmentier
Influence Of Sea Ice On Arctic Precipitation, Ben G. Kopec, Xiahong Feng, Fred A. Michel, Eric S. Posmentier
Dartmouth Scholarship
Global climate is influenced by the Arctic hydrologic cycle, which is, in part, regulated by sea ice through its control on evaporation and precipitation. However, the quantitative link between precipitation and sea ice extent is poorly constrained. Here we present observational evidence for the response of precipitation to sea ice reduction and assess the sensitivity of the response. Changes in the proportion of moisture sourced from the Arctic with sea ice change in the Canadian Arctic and Greenland Sea regions over the past two decades are inferred from annually averaged deuterium excess (d-excess) measurements from six sites. Other influences on …
Coastal Ice-Core Record Of Recent Northwest Greenland Temperature And Sea-Ice Concentration, Erich C. Osterberg, Robert L. Hawley, Gifford Wong, Ben Kopec, David Ferris, Jennifer Howley
Coastal Ice-Core Record Of Recent Northwest Greenland Temperature And Sea-Ice Concentration, Erich C. Osterberg, Robert L. Hawley, Gifford Wong, Ben Kopec, David Ferris, Jennifer Howley
Dartmouth Scholarship
Coastal ice cores provide an opportunity to investigate regional climate and sea-ice variability in the past to complement hemispheric-scale climate reconstructions from ice-sheet-interior ice cores. Here we describe robust proxies of Baffin Bay temperature and sea-ice concentration from the coastal 2Barrel ice core collected in the Thule region of northwest Greenland. Over the 1990–2010 record, 2Barrel annually averaged methanesulfonic acid (MSA) concentrations are significantly correlated with May–June Baffin Bay sea-ice concentrations and summer temperatures. Higher MSA is observed during warmer years with less sea ice, indicative of enhanced primary productivity in Baffin Bay. Similarly, 2Barrel annually averaged deuterium excess (d-excess) …
Open Access Data In Polar And Cryospheric Remote Sensing, Allen Pope, W. Rees, Adrian Fox, Andrew Fleming
Open Access Data In Polar And Cryospheric Remote Sensing, Allen Pope, W. Rees, Adrian Fox, Andrew Fleming
Dartmouth Scholarship
This paper aims to introduce the main types and sources of remotely sensed data that are freely available and have cryospheric applications. We describe aerial and satellite photography, satellite-borne visible, near-infrared and thermal infrared sensors, synthetic aperture radar, passive microwave imagers and active microwave scatterometers. We consider the availability and practical utility of archival data, dating back in some cases to the 1920s for aerial photography and the 1960s for satellite imagery, the data that are being collected today and the prospects for future data collection; in all cases, with a focus on data that are openly accessible. Derived data …
Plastic Faulting In Saltwater Ice, Narayana Golding, Scott A. Snyder, Erland M. Schulson, Carl E. Renshaw
Plastic Faulting In Saltwater Ice, Narayana Golding, Scott A. Snyder, Erland M. Schulson, Carl E. Renshaw
Dartmouth Scholarship
Compression experiments on laboratory-grown columnar S2 saltwater ice loaded triaxially through proportional loading at T = –20°C at applied strain rates of ε = 10–5–10–1 s–1 demonstrate that plastic (P) faulting is a mode of failure in saltwater ice when rapidly loaded under a high degree of confinement. In terms of microstructure, mechanical behavior and strength, saltwater ice that fails via P-faulting is almost indistinguishable from columnar S2 freshwater ice that fails via P-faulting loaded under the same conditions. The results also demonstrate that saltwater ice loaded rapidly may exhibit yet another mode of failure, in addition to P-faulting, through …
Brittle Compressive Failure Of Ice: Proportional Straining Vs Proportional Loading, E. M. Schulson, D. Iliescu
Brittle Compressive Failure Of Ice: Proportional Straining Vs Proportional Loading, E. M. Schulson, D. Iliescu
Dartmouth Scholarship
Proportional straining experiments have been performed on columnar-grained S2 fresh- water ice biaxially compressed across the columns at –108C at a strain rate of (4.5 1.5) 10–3 s–1. The results are compared with those obtained earlier (Iliescu and Schulson, 2004) from the same kind of material deformed to terminal failure under the same conditions, but through proportional loading. The exercise shows that the biaxial strength is practically independent of the path taken, at least under low confinement where Coulombic shear faulting limits terminal failure. First-year sea ice is expected to exhibit the same behavior.
The Fracture Of Ice On Scales Large And Small: Arctic Leads And Wing Cracks, E. M. Schulson, W. D. Hibler
The Fracture Of Ice On Scales Large And Small: Arctic Leads And Wing Cracks, E. M. Schulson, W. D. Hibler
Dartmouth Scholarship
From observations and calculations of crack patterns in ice, it is suggested that a similar mechanism may account for cracking over a wide range of scales.