bluuebunny/crossref_metadata_2025_split huggingface dataset:
Instruments and Methods: Sampling Characteristics of Neutron Probe Measurements in a Mountain Snow Pack
Authors: Cooper Charles F. 
Published: September 2017

AbstractAdvantages of neutron moisture probes over standard snow sampling tubes include integration of water content over a greater horizontal extent, easier measurement of snow layering, and possible increase in accuracy through elimination of the need to extract a full core. However, the neutron probe is better suited for evaluation of water content changes with time at a fixed location, as in soil moisture studies, than for measurement of the total water content of a variable snow pack. Field tests in the mountains of Idaho, U.S.A., showed statistically significant differences among mean snow densities determined by a neutron probe in closely spaced holes at a single sampling station. Within-station variance was about the same as with a conventional snow tube. There were significant differences in density for a given depth from hole to hole, but statistical interactions make it difficult to interpret these differences. There was a poor correlation between measurements made in the same hole with a neutron probe and with a snow sampling tube.
Observations at the Bogvatn Glaciers, Norway
Authors: Theakstone W. H. 
Published: September 2017

AbstractA description of the two glaciers n. Bogbre and s. Bogbre is given. In summer 1965 snow pillars capped with avalanche material were seen. A blister-shaped swelling which appeared on the surface of s. Bogbre and which emitted water when punctured is discussed.
Density Variations in Alpine Snow
Authors: Alford Donald 
Published: September 2017

AbstractStratigraphic studies of the annual snow layer in the Beartooth Mountains of south-western Montana and on Mount Logan in the St. Elias Range have disclosed a similiar distribution of at least one physical property of the snow pack in the two areas. The average density of the pack, obtained by integrating a series of measurements taken at 5–10 cm. vertical intervals over the total thickness of the annual layer, reaches a maximum value near a mid-point of the total elevation covered by each traverse and decreases linearly toward the elevation extremes. A preliminary hypothesis, relating the distribution of average snow-density values along slopes to a semi-stable zonation of near-surface air temperatures, is presented.
Preliminary Studies on Sea Ice in McMurdo Sound, Antarctica, During “Deep Freeze 65”
Authors: Paige Russell A. , Lee Claude W. 
Published: September 2017

AbstractThe sea ice in McMurdo Sound, Antarctica, is extensively utilized for runways, travel, freight hauling and docking facilities. The safety and efficiency of these operations depend upon a better understanding of the sea-ice bearing strength.Variations in shear and tensile strength, decreased thickness, salinity changes, internal deterioration and changes of the temperature gradient are all related to and dependent upon snow cover, ambient temperatures and solar radiation. During the austral summer of 1964–65, shear strength decreased from 9.8 kg./cm.2 in October to 6.3 kg./cm.2 in late January and then increased to 8.0 kg./cm2. by 10 February. The salinity of collected brine decreased from 125 p.p.t. in November to 43 p.p.t. in January. Thickness increased until mid-December, then decreased rapidly by bottom melting until break-out in February. In the Cape Armitage shoal area, thickness decreased from 2.5 m. in mid-December to 36 cm. in late January. Snow cover significantly affects the degree of internal deterioration and the amount of strength loss during the summer. Sea ice with more than 6 cm. snow cover is consistently stronger than unprotected ice and deterioration is less. Bearing strength of the sea ice is sufficient for most ordinary loads throughout the period of most extensive use.
Observations on the Snow Line in the Peruvian Andes
Authors: Hastenrath Stefan L. 
Published: September 2017

AbstractObservations on both the modern and Pleistocene snow lines were made during a journey through the Peruvian Andes. En route observations were supplemented by an evaluation of air photographs in the Servicio Aerofotográfico Nacional in Lima and a survey of the literature. The large-scale variation of the Pleistocene snow-line depression is discussed with respect to possible palaeoclimatic implications.
Accumulation Between Mount Chapman and “Byrd” Station, Antarctica
Authors: Brecher Henry H. 
Published: September 2017

AbstractIn November and December 1965 accumulation measurements were made at 3 km. intervals and at networks of poles at six photogrammetric arrays on an oversnow traverse from Mount Chapman to “Byrd” station. The results at the photogrammetric arrays, which yield a mean accumulation of 16.4 g. cm.−2 yr.−1 for 1963–65, are compared with values determined from stratigraphic investigations in 1958–59 and in 1962–63, which gave 12.2 g. cm.−2 yr.−1 and 13.2 g. cm.−2 yr.−1, respectively.
The Development of a Complex Supraglacial Moraine at the Margin of Sørbreen, Ny Friesland, Vestspitsbergen
Authors: Boulton G. S. 
Published: September 2017

A series of concentric debris bands crop out on the frontal stagnant zone of Sørbreen, Ny Friesland, Vestspitsbergen. The contained debris, which is dominantly sand and silt with some clay and gravel, is well sorted and banded, and it is thought to be derived from subglacial fluvial deposits. These debris bands give rise to a complex series of bedded moraine ridges, and bedded and unbedded sediment sheets on the glacier surface.The development of a supraglacial hummocky moraine is traced and it is composed of several elements: supraglacial ridges, kettle-holes, and flowed sediment sheets, which are derived from debris bands; supra-glacial fluvial deposits and clay-silt ablation tills; and englacial fluvial deposits. It is also suggested that large areas of the outwash plain are underlain by dead glacier ice.From the present work there are several possible implications for the interpretation of Pleistocene deposits:i.Certain types of “controlled disintegration features” may have formed supraglacially from debris bands. Some bedded features hitherto interpreted as Huvioglacial in origin may be supraglacial moraines.ii.Certain types of “kame-and-kettle“moraine may be mainly supraglacial in origin.iii.Complex sequences of tills and bedded sediments may have been formed during a single glacier retreat phase rather than by multiple advance and retreat.
The Formation of Shear Moraines: an Example from South Victoria Land, Antarctica
Authors: Souchez R. A. 
Published: September 2017

An analysis of the margin of the ice sheet in the upper Ferrar Glacier area of south Victoria Land, Antarctica, shows that the shear hypothesis and the theory of Weertman are both of value if an attempt is made to explain the formation of the morainic deposits of this area.Three types of debris layer have been observed within the glacier:
i.Silty and sandy layers, with a slight dip towards the interior of the glacier, are separated from one another by white bubbly ice and blue dense ice at the edge of the glacier. They have resulted from a freezing-in process due to the formation of segregation ice and upwarping near the margin of the ice sheet.ii.Fault planes in the glacier, filled with slabs and gravel, are the result of shearing which has occurred along and transformed thermal-contraction fissures. The debris has been scraped from the glacier bed, carried into the ice and ultimately transported along these planes.iii.Three coarse debris layers of different ages associated with major shear zones at the boundary between stagnant and active ice.Due to favourable circumstances, the debris layers of Weertman have been observed to be faulted by shear planes of the second type.
Desalination Features in Natural Sea Ice
Authors: Bennington Kenneth O. 
Published: September 2017

Salinity profiles of young sea ice are presented which show salinity differences of the order of 2‰ to 3‰ within a ~3 cm. distance, horizontally as well as vertically. This ice is also shown, by use of a penetrating dye, to be very permeable which encumbers any attempt to explain such pronounced salinity variations. Two generations of brine-drainage features are described; the first is inherited from the liquid and the later-generation channels develop from brine-pocket and Tyndall-figure migration.It is proposed that at least part of the brine contained in the ice mass migrates downward in the following way: cold dense brine cascades from higher levels, causing the more dilute, warmer brine at lower levels to partially freeze. This would also account for some of the local variations in salinity.
The Effect of Absorbed Solar Radiation on the Thermal Diffusion in Antarctic Fresh-Water Ice and Sea Ice
Authors: Weller G. 
Published: September 2017

Ice temperatures were measured on the ice plateau at Mawson, Antarctica, for one year down to depths of 11 m. and through a floating sea-ice cover for six months. The plateau data were examined by harmonic analysis and the thermal diffusivity of the ice was obtained from the classical model of heat diffusion. An improved model of heat diffusion proposed by Lettau (1954) was also used to derive the diffusivity. The results show that absorbed radiation affects the computed diffusivity values down to 6–8 in. depth and a model is put forward to explain these apparent changes with depth. Data on the extinction of radiation in the ice have been published elsewhere (Weller and Schwerdtfeger, in press). The diffusivity of the ice is determined for periods with no radiation in winter and the value of 0.011 cm2. sec−1 agrees well with values at 8 m. depth where the effect of radiation becomes negligible.Heat-flux plates embedded in the ice were used to determine the diffusivity independently and also to give numerical values of the heat flux at any moment. The geometry and characteristics of these flux plates are discussed elsewhere (Schwerdtfeger and Weller, 1967). They are also used to derive the diffusivity of sea ice and enable a detailed analysis of the diurnal heat flux in such complex substances as sea ice to be made.
Snow Accumulation Studies on the Thule Peninsula, Greenland
Authors: Mock Steven J. 
Published: September 2017

AbstractData 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.
Hexagonal and Cubic Ice at Low Temperatures
Authors: Kumai Motoi 
Published: September 2017

AbstractThe formation of hexagonal and cubic forms of ice was studied by the use of a cold stage in an electron microscope within the temperature range −90° to −180° C. Ice crystal specimens were made on cold substrates, i.e. a collodion film, gold foil, or copper grid on the specimen holder of the cold stage. The hexagonal form of ice formed on the cold substrates at temperatures from−90° to−100° C. At −100° to −130° C, both hexagonal and cubic forms of ice were detected. From −130° to −160° C only cubic ice was found. At temperatures below −160° C, minute crystals of cubic ice were detected. No transformation of the structural form of ice from hexagonal to cubic or from cubic to hexagonal occurred when the temperature of the specimens was varied in the range −90° to −160° C. The lattice constants of hexagonal and cubic ice, and the coefficient of thermal expansion of ice were calculated from the experimental results.
Steady-State Temperatures at the Bottom of Ice Sheets and Computation of the Bottom Ice Flow Law from the Surface Profile
Authors: Lliboutry L. 
Published: September 2017

AbstractA solution for the steady flow of a cold ice sheet is recalled, which takes account of the heat released by deformation. As this strain heating increases the strain velocity, the bottom temperature may be unstable. A set of five equations with five unknowns is written, which allows the surface profile and the bottom temperature to be computed step by step by an iterative process. This has been done by computer for three very different models of ice sheets. and in each case with three distinct values of the constant B in Glen’s ice flow law. It was found in every case that steady-state temperature profiles could not be computed beyond a moderate distance from the ice divide. The correct value of B for bottom ice may be deduced from the actual surface profile. At the bottom of Greenland ice sheet, B ≈ 2.18 bar −3 year−1. This is about thirteen times bigger than for the bulk of the alpine glaciers.
Flow Tills and Related Deposits on Some Vestspitsbergen Glaciers
Authors: Boulton G. S. 
Published: September 2017

AbstractThree outlet glaciers of the highland ice of Ny Friesland are described, in which englacial debris, derived from the glacier bed, occurs in thick bands which dip steeply up-glacier. As the glacier wastes down this debris is released on the surface to form thick supraglacial tills, which may remain on the glacier surface, or flow down it and onto bedded deposits which fringe the glacier in the proglacial zone. A frequent result of this latter process is the production of multi-till sequences which result from a single glacier retreat phase rather than multiple advance and retreat. The sedimentological features and fabrics of englacial debris bands and flow tills are described, and a mechanism for the formation of “controlled” and “uncontrolled” hummocky moraine is suggested. Many flow tills are identical to the compact fine-grained tills common in lowland glacial deposits of Pleistocene age in Europe and North America, and it is suggested that some of the latter could be flow tills.
Coastal Geomorphology, McMurdo Sound, Antarctica
Authors: Nichols Robert L. 
Published: September 2017

AbstractWell-developed elevated beaches. deltaic deposits, marine-boulder pavements and wave-washed bedrock surfaces are found from Cape Bernacchi north to Granite Harbour. The highest measured marine feature, an elevated beach at Dunlop Island, is 20 m (67 ft) above sea-level. The highest beaches at Marble Point and Cape Roberts, about 48 km (30 miles) apart, are about 20 m (66 ft) above sea-level. The marine limit between these two points is, therefore, essentially horizontal. The highest beach at Cape Bernacchi. approximately 4.8 km (3 miles) south of Marble Point, is about 12 m (40 ft) above sea-level, Well-developed elevated beaches disappear about 3.2 km (2 miles) south of Cape Bernacchi and are not found between this point and Koettlitz Glacier.These beaches post-date the youngest glaciation recognized in the lower Wright Valley. A 14C analysis of an elephant seal buried in a 13 m (44 ft) beach at Marble Point indicates that this beach is 4450 ± 150 years old. As sea-level at this time was approximately 3 m (10 ft) lower than at present. the Marble Point area has risen isostatically about 16 m (54 ft) during the last 4450 ± 150 years.Pitted beaches, beaches deposited on ice, a buried elephant seal and gravel ridges deposited by ice indicate that all of the beaches were formed in a climate like that now found in the area.
Present-Day Glaciers in the U.S.S.R. and Some Data on their Mass Balance
Authors: Grosval’d M. G. , Kotlyakov V. M. 
Published: September 2017

There are four major glacier regions in the U.S.S.R.: the Atlantic-Arctic, Atlantic-Eurasian, East Siberian and Pacific-Asian, which can be divided into 19 separate glacier areas. The total area of the glaciers in the country amounts to 81 900 km2, and the volume of water stored in them to 13 750 km3.The main characteristic features of glacier regime, such as the elevation of the equilibrium line, the value of the total accumulation at the equilibrium line, the vertical gradients of net balance, the “glacier ratios”. etc., are estimated for the majority of the glacier areas. The data on mass balance of the glaciers in the Polar Urals and Tien Shan which were obtained by direct measurement during the last decade are tabulated and compared. It has been found that the glacier balance changes in the two areas are nonsynchronous.A comparison of the variations in mass balance of the Lednik IGAN in the Polar Urals, and the Grosser Aletschgletscher in the Swiss Alps, over a period of several decades suggests a cyclic trend of the variations in both regions (with a wave-length of about 22 years), and the direct opposition in their phase. The analogy of 22-year cycles of the balance variations with the cyclic fluctuations of the same wave-length in solar activity seems to be quite evident, whereas the atmospheric circulation appears to be one of the main intermediate variables in the chain sun-glaciers responsible for the out-of-phase relationship in glacier variations of certain areas.In conclusion, some data on the present changes in glacier regime are given, as well as general information on glaciological studies carried on in the U.S.S.R. within the framework of the I.H.D. programmes. The latter include the compilation of the Soviet Union inventory of perennial snow and ice masses, the continuous measurement of glacier variations, and the research on combined heat, mass and water balances at selected mountain glacier basins.
The Equilibrium State of the Eastern Half of the Ross Ice Shelf
Authors: Thomas Robert H. , Bentley Charles R. 
Published: September 2017

AbstractMeasurements of ice thickness, velocity, snow accumulation rates, and surface strain-rates are used to examine the state of equilibrium of three flow bands of the Ross Ice Shelf. The analysis gives the rate of thickening of the ice shelf in terms of the basal freezing rate, which is unknown. However, indirect evidence suggests that the basal flux ranges from a small value of freezing in the south to a melting rate of about one meter of ice per year at the ice front. If these values are correct then the flow band in the south-east corner of the ice shelf appears to be thickening at an average value of (34 ± 15) cm of ice per year. Persistent thickening at this rate must lead to grounding of large areas of the ice shelf. This would restrict drainage from West Antarctic ice streams which feed this part of the ice shelf and these would tend to thicken and advance their grounding lines into the ice shelf. Further north, near the RISP bore-hole site, the ice shelf is probably in equilibrium. The largest flow band is to the south and east of Roosevelt Island, and this also may be in equilibrium if there is significant bottom melting from ice shelf that is more than 100 km from the ice front.
Numerical Modelling of Iceberg Towing for Water Supplies—A Case Study
Authors: Job J.G. 
Published: September 2017

AbstractsThe towing of unprotected icebergs from the Antarctic continent (66° S.) to latitude 38° S. has been simulated using an explicit hydrodynamic model and an extended two-dimensional melting model. It was found that nominal towing accelerations in excess of 2 × 10-5 m s-2 were required to deliver ice over this route in most circumstances, and minimum energy consumptions were obtained at accelerations around 10-4 m s-2. Unprotected icebergs could be delivered with about 50% yield to latitude 38° S., but the rate of deterioration in the warm waters indicates that protection would be required for longer journeys. The towing simulation was most sensitive to north-south current components, the total towing distance and the rate of iceberg deterioration. Efforts directed towards locating suitable icebergs in the region 50° S. to 60° S., and towards increasing knowledge of the changing current patterns in the Southern Ocean would be most valuable, as would a knowledge of the mechanisms and rates of deterioration of icebergs in warm seas.
Fabric and Origin of Lateral Moraines, Bethartoli Glacier, Garhwal Himalaya, India
Authors: Osborn Gerald D. 
Published: September 2017

AbstractUnusually strong till fabrics in lateral moraines of Bethartoli Glacier provide information on the genesis and growth of the moraines. On the west side of the valley, down-stream of the present glacier snout, several lateral moraine crests are juxtaposed. Because the crests generally become higher towards the valley axis, they must represent re-advances of the glacier rather than recessional stages. On the east side of the valley only a single lateral ridge is found; presumably the ridge is composed of debris from several glacial advances. On the eroded proximal flank of this ridge a strong fabric is visible; the plane defined by a- and b-axes of stones is parallel to the distal flank of the moraine ridge, indicating that the moraine grew mainly by accretion of debris on to its distal flank. On the eroded proximal flank of the innermost west-side ridge the equivalent fabric is weaker, suggesting that distal flank accretion was less significant and proximal flank accretion more significant than on the east side.
An Inexpensive Tensiometer for Snow-Melt Research
Authors: Wankiewicz Anthony , Vries Jan De 
Published: September 2017

AbstractThe construction and use of a rugged and easily installed tensiometer for use in snow hydrology is discussed. The tensiometer incorporates a short (380 mm) water manometer, adequate for the small range of capillary pressure in melting snow. The response of a row of tensiometers to the application of a dyed water pulse to the snow surface is compared to the resulting dye stain pattern. The lateral variation of flow in a snow-pack requires the use of many tensiometers to define the capillary pressure regime.
Migration of Insoluble and Soluble Impurities in Temperate Ice: Study of a Vertical Ice Profile Through the Glacier Du Mont De Lans (French Alps)
Authors: Ricq-de Bouard M. 
Published: September 2017

AbstractIce samples representing at least some twenty years' accumulation, have been collected from a crevasse wall at 3 200 m (Glacier du Mont de Lans, Massif de l'Oisans), with a view to studying the behaviour of soluble and insoluble impurities in temperate ice. The stratification of the ice from the surface to 2 m and the disappearance of this stratification below 2 m are attributed to a variation in the glacier regime on both sides of the equilibrium line, rather than to a variation in the conditions of deposit of solid debris on the glacier surface, the strata do not necessarily correspond to an annual accumulation. Mineralogical analysis of the solid particles has allowed us to demonstrate two kinds of deposit: that consisting of the local Alpine material (hornblende) and that consisting of a mixture of local material and red sand of Saharan origin (anatase). A study of the distribution of major cations (Na, K, Mg, Ca) along a profile has revealed the existence of a process of leaching which follows an exponential law to a first approximation. The leaching produces a rapid evolution in the chemical properties of the ice compared with those of the original precipitation.