Snow Accumulation Studies on the Thule Peninsula, Greenland

Abstract

Data from stake measurements, marker boards and pits along a 136 km trail crossing the Thule peninsula sector of the Greenland ice sheet have been used to determine both the regional and local distribution of snow accumulation, On a regional scale trend surfaces of mean annual accumulation can be adequately predicted from a model using distance from moisture source and elevation as independent parameters. A series of step- or wave-like features break the smooth profile of the ice. sheet and cause profound changes in accumulation rates on a local scale. The accumulation pattern over these features can be predicted from surface slope and departure from regional elevation. Profiles of’ surface and subsurface topography indicate a direct relationship between subsurface hills and step-like features, but cannot be quantitatively accounted for by existing ice-flow theory. Detailed accumulation studies in conjunction with a program of spirit leveling in the vicinity of Camp Century has revealed the development a shallow valley-like feature. Within this feature accumulation rates have increased indicating that it is the result of flow phenomena.

Accumulation, Ablation, and Oxygen Isotope Variations on the Queen Elizabeth Islands Ice Caps, Canada

“…The high accumulation rate on these slopes was first discovered during studies of the Devon Island ice cap by Koerner (1966) and is now the subject of intense studies by F. Müller and coworkers (personal communication). Mock (1968) also found very high accumulation rates in Greenland on southerly slopes facing Baffin Bay. The area, which we might consider bounded by the 40 cm isohyet (Fig.…”

“…This emphasizes that the main mechanism in producing the high accumulation-rate is an orographic one, but this will be discussed more fully later. On the southern side of the Thule peninsula in Greenland (Figs 1 and 2) the accumulation gradient was 0.4 g km –1 for the 3 year period 1962–65 (Mock, 1968). This is especially steep.…”

“…The high-accumulation area does not, therefore, extend south of Devon Island. The area of highest accumulation on the Greenland side of Baffin Bay appears to be on the south-facing slopes below Camp Century where accumulation rates reach 80 g cm –2 year –1 (Mock, 1968); the detailed pattern between Inglefield Bay and Inglefield Land is not known, but in general the isohyets show no unusual trends between the Queen Elizabeth Islands and Greenland (Fig. 2).…”

Comparison between measured and theoretical temperature profiles of the Camp Century, Greenland, Borehole

“…rapped air, their volume at depths below 70 meters is inversely proportional to the overburden pressure. The horizontal temperature gradient has been measured only at the surface [Mock, 1967]. Its value a• depth can be calculated when V• --0 by differentiating (1) if, as it is reasonable to assume, the geothermal heat does not vary appreciably with x and the average horizontal temperature gradient is small in comparison to the average vertical temperature gradient.…”

Multiple glaciations and marine transgressions, western Kennedy Channel, Northwest Territories, Canada

“…This favorable glacio-climatic regime clearly reflects the presence of increased cyclogenesis and orographic precipitation occasioned by the 'North Water', a major polynya in northern B a n Bay (Koerner 1979). The contemporary influence of the 'North Water' on the glaciers of northern Baff'im Bay has been previously demonstrated by Koerner (1966) and Mock (1968), who show substantial increases in snow accumulation on southeastern Devon Island and the Thule Peninsula, respectively. More recently this glacio-climatic influence of B a n Bay has been demonstrated to extend back into the early Holocene as shown by the asymmetric profiles on the ice caps of central Ellesmere and Devon islands which have disproportionately thickened in their eastern sectors (Koerner 1977).…”