Statistical results of measurements of glacier variations in Switzerland 1891–1965 are compared with deviations from average temperature and precipitation in summer for stations above 2000 m. The result is interpreted in terms of meso-scale glacier–weather relations. A correlation between glacier mass budget and deviation from the average height of the 500 mbar surface indicates the importance of cyclonic and anticyclonic conditions during the ablation period, and therefore of the frequency of certain Grosswetterlagen which has been studied for the period 1881–1965. The pattern of the difference of Grosswetterlagen favourable and unfavourable for glaciers resembles the pattern of glacier variations and also of mass-budget data. Atmospheric circulation in zonal and meridional forms, as expressed by the frequency of Grosswetterlagen has to be considered by seasons. There is no simple relation between the intensity of zonal circulation and glacier variation. Glacier recession of the last few decades seems to be caused by the fact that meso-scale weather conditions mainly in the ablation season have become much less cyclonic than in the decades 1886–95 and 1906–15.

Earlier theories of Weertman and the present author are reviewed and compared; both are insufficient to account for the facts observed at the tongue of the Allalingletscher.

A calculation of the stresses and heat flow at the bed of a glacier with a sinusoidal profile is given which takes account of any degree of subglacial cavitation. The sliding due to plasticity and that due to pressure melting are related to this degree of cavitation and it is shown that these two terms are additive. There results an expression for the friction fω in terms of the total sliding velocity u and the height of the bumps a. For a given and large enough value of u, fω(a) exhibits two maxima which are equal and independent of u.

The paper then considers a more realistic model of the bed consisting of a superposition of sine waves all having the same roughness r, and a decreasing in a geometrical progression. The biggest a may be inferred from the overall profile of the bedrock; the resulting frictional force can be regarded either as part of the total frictional force f in an overall view for which f = ρgh sin α holds, or else as a correction to such a value on the small scale (the best point of view for crevasse studies). To a first approximation Coulomb’s law of friction holds provided one takes account of the interstitial water pressure at the ice-rock interface.

This interstitial pressure p is next related to the thickness of the glacier h. If the subglacial hydraulic system is at atmospheric pressure, p is proportional to h. Next, if the sliding velocity is not too large, the surface slope approaches 1.6r ≈ 0.12 and kinematic waves (which move four times as fast as the ice) disappear rapidly. If the hydraulic system is not at atmospheric pressure the surface slope is smaller and flow instabilities can occur.

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.

Recent glacial deposits in the Indian Peaks area of the Colorado Front Range have been dated lichenometricaily, using a growth curve developed locally for Rhizocarpon geographicum. Radiocarbon dates, where available, tend to support the lichen chronology. Three distinct intervals of glaciation, each consisting of several minor pulsations, have occurred in the area during the past 4500 years. The earliest advance (Temple Lake Stade) is dated at 2500–700 b.c. A later advance (Arikaree Stade) began in about a.d. 100 and ended in a.d. 1000. The most recent advance (Gannett Peak Stade) is dated at a.d. 1650–1850. It remains to be seen whether the Arikaree Stade was purely a local development or whether glaciers were advancing elsewhere in the cordilleran region during this interval. Alluviation on the plains east of the Colorado Front Range seems to have occurred during the waning stages of mountain glaciation.

Field measurements are presented of dielectric absorption in Antarctic snow and ice at frequencies of a few hundred megahertz. They are compared with measurements by other authors at very high frequencies. The dielectric absorption in ice at these frequencies is accounted for in terms of absorption bands both at radio frequencies and in the infrared. Bands at radio frequencies are caused by a relaxation mechanism which depends upon the temperature and the impurity content of the ice. These two factors are therefore included in an account of the dielectric absorption in ice at very high frequencies.

The 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.

A device is described which automatically measures the thickness of a floating ice cover at regular or any desired times and allows the result to be printed together with the time on a shore-based recorder. This instrument has been proven by a year’s operation near Mawson, Antarctica.

The problem of erratic boulders lying far from their place of origin attracted considerable attention during the closing decades of the eighteenth century. More especially, interest focused upon the blocks of Mont Blanc granite resting on the flanks of the Jura. Various fanciful explanations, ranging from debacles to gigantic explosions, were offered to account for such phenomena (some of the early explanations have been reviewed by Agassiz (1840) and North (1943)) but the true explanation long eluded even the most astute observers. It was not that there was a failure to appreciate the transportive power of glaciers—de Saussure (1786–96, Vol. 2, p. 21) and others recognized the ability of glaciers to move large boulders—but a failure to recognize that glaciers had recently extended far beyond their present limits.

The steady profile of a finite-amplitude kinematic wave on a glacier is calculated with the assumption that the wave velocity varies linearly with h1, the departure of the ice thickness from the datum state. If the flow of ice is due mainly to sliding of the glacier on its bed, the width of the calculated steady profile is several hundred times the datum state ice thickness. The width of an observed kinematic wave front on Nisqually Glacier, Mt. Rainier, Washington is at least an order of magnitude smaller than the calculated steady profile. This indicates that the observed steepening of the wave may be due to effects other than variation of wave velocity with ice thickness.