We present the results of preliminary investigations of globular moss growth on the surface of Falljökull, a temperate outlet glacier of the Vatnajökull ice cap, southern Iceland. Supraglacial debris has provided a basis for moss colonization, and several large (>500m2) patches of moss growth (Racomitrium spp.) are observed on the surface of the glacier. Each area of moss-colonized supraglacial debris shows a downslope increase in sphericity and moss cushion size and a decrease in percentage surface coverage of moss-colonized and bare clasts. It is suggested that moss growth on supraglacial debris allows preferential downslope movement of clasts through an associated increase in both overall mass and sphericity. Thermal insulation by moss cushions protects the underlying ice surface from melt, and the resulting ice pedestals assist in downslope sliding and toppling of moss cushions. The morphology and life cycle of supraglacial globular mosses is therefore not only closely linked to the presence and distribution of supraglacial debris, but also appears to assist in limited down-glacier transport of this debris. This research highlights both the dynamic nature of the interaction of mosses with supraglacial sedimentary systems and the need for a detailed consideration of their role within the wider glacial ecosystem.

Regional climate warming has caused several ice shelves on the Antarctic Peninsula to retreat and ultimately collapse during recent decades. Glaciers flowing into these retreating ice shelves have responded with accelerating ice flow and thinning. The Wordie Ice Shelf on the west coast of the Antarctic Peninsula was reported to have undergone a major areal reduction before 1989. Since then, this ice shelf has continued to retreat and now very little floating ice remains. Little information is currently available regarding the dynamic response of the glaciers feeding the Wordie Ice Shelf, but we describe a Chilean International Polar Year project, initiated in 2007, targeted at studying the glacier dynamics in this area and their relationship to local meteorological conditions. Various data were collected during field campaigns to Fleming Glacier in the austral summers of 2007/08 and 2008/09. In situ measurements of ice-flow velocity first made in 1974 were repeated and these confirm satellite-based assessments that velocity on the glacier has increased by 40–50% since 1974. Airborne lidar data collected in December 2008 can be compared with similar data collected in 2004 in collaboration with NASA and the Chilean Navy. This comparison indicates continued thinning of the glacier, with increasing rates of thinning downstream, with a mean of 4.1 ± 0.2 m a−1 at the grounding line of the glacier. These comparisons give little indication that the glacier is achieving a new equilibrium.

Dual-frequency, multi-polarization airborne synthetic aperture radar (Pi-SAR; developed by the Communications Research Laboratory and National Space Development Agency of Japan) observations of the seasonal sea-ice region off the Okhotsk coast of Hokkaido, Japan, were carried out in February 1999 using X- and L-band radar frequencies with a resolution of 1.5 and 3.0 m. In conjunction with the SAR observations, the sea-ice thickness (draft) and velocity were measured by a moored Ice Profiling Sonar (IPS) and an Acoustic Doppler Current Profiler (ADCP). Tracks of the sea ice passing over the IPS were estimated from the time series of the ADCP ice-velocity and -direction data. Along these tracks, the SAR backscattering coefficient profiles were compared with the IPS ice-draft profiles. The results showed that the L-band SAR backs cattering profiles correlated well with the IPS ice-draft data, particularly in the thicker part (a few meters thick) of the rim of first-year ice, which had a large backscattering coefficient. Although the X-band SAR backscattering profiles did not correlate well with the IPS data, thin ice (<10 cm thick) showed a large backscattering coefficient. The L-band SAR and IPS data did not distinguish thin ice from open water.

Ever since the first deep ice cores were drilled, it has been a challenge to determine their original, in-situ orientation. In general, the orientation of an ice core is lost as the drill is free to rotate during transport to the surface. For shallow ice cores, it is usually possible to match the adjacent core breaks, which preserves the orientation of the ice column. However, this method fails for deep ice cores, such as the EastGRIP ice core in Northeast Greenland. We provide a method to reconstruct ice core orientation using visual stratigraphy and borehole geometry. As the EastGRIP ice core is drilled through the Northeast Greenland Ice Stream, we use information about the directional structures to perform a full geographical re-orientation. We compared the core orientation with logging data from core break matching and the pattern of the stereographic projections of the crystals’ c-axis orientations. Both comparisons agree very well with the proposed orientation method. The method works well for 441 out of 451 samples from a depth of 1375–2120 m in the EastGRIP ice core. It can also be applied to other ice cores, providing a better foundation for interpreting physical properties and understanding the flow of ice.

Records of recent oxygen isotope ratios (δ18O) and accumulation rates are presented for the region of Wilhelm II Land, East Antarctica, between 78˚ and 93˚E and from the coast to 2100m elevation. These records were derived from analysis of 21 shallow firn cores collected during the 1997/98 and 1998/99 Australian National Antarctic Research Expeditions summer operations. the accumulation rates were determined using comparisons between detailed analyses of density, δ18O, hydrogen peroxide (H2O2) levels and electrical conductivity. the δ18O distribution follows an approximately linear relationship with snow surface elevation, with values from –22‰ near the coast to –32‰ towards 2000m elevation. Accumulation-rate distribution does not display this simple relationship with topography. South of the West Ice Shelf the contours run parallel to lines of latitude (oblique to the coast and topography), with 400 kg m–2 a–1 towards the coast and 2000m elevation, and a lower zone of 300 kg m–2 a–1 along an axis of 68.4˚ S. This pattern of accumulation is also evident along the Mirny–Vostok traverse route. Southwest of the West Ice Shelf the rate of accumulation drops gradually from 300 to 200 kg m–2 a–1 towards Lambert Glacier basin. Surface-snow redistribution and variations in accumulation rate cause variability in the clarity of core records, but several sites show sufficient stratigraphic preservation to suggest potential for extraction of extended palaeoenvironmental records through further drilling.

Glacier mass balance and hydrology are strongly influenced by the distribution of snow accumulation at the start of the melt season. Two successive end-of-winter snow-cover surveys at Finsterwalderbreen, Svalbard, are here used to investigate the interannual variability in the spatial distribution of accumulation, and its relationship with topography. 40–62% of the variance in snow depth was not determined by elevation (assessed by linear regression of snow depth on surface elevation), which could not therefore necessarily be used as a sole predictor of the spatial distribution of accumulation here. Principal components (PC) analysis of the topographic variables elevation, slope, north–south and east–west aspects shows that only two of six PCs, determined for 2years’ sampling locations, had maximum loadings on altitude; aspect was more important, with maximum loadings on four PCs. Hierarchical cluster analysis was then applied to these PCs: significant correlations with accumulation in each of two terrain clusters were given by (1) elevation and slope, (2) east–west aspect only (1999); (1) elevation only, (2) no significant correlations (2000). There is strong interannual variability not only in the magnitude of winter accumulation (0.41 mw.e. in 1999, 0.58 mw.e. in 2000), but also in its spatial distribution, and its relationship with topography.

A survey of available mass-balance data shows that glaciers on arctic islands, i.e. mountain glaciers and ice caps in northern Canada, Greenland, Svalbard and the Eurasian islands, share mass-balance characteristics of low annual amplitude and small interannual variability. By contrast, glaciers around the Arctic (e.g. in Alaska, Iceland, mainland Scandinavia and northern Eurasia) can have exceptionally large annual amplitude and interannual variability but otherwise share characteristics with glaciers in lower latitudes. The arctic island glaciers occur in areas with low annual precipitation and high annual temperature variability, i.e. in dry-cold or continental regions. Most glaciers surrounding the Arctic (Alaska, Iceland and Scandinavia) occur in areas with high annual precipitation and low annual temperature variability, i.e. in wet-warm or maritime regions. Earlier mass-balance modelling showed that arctic island glaciers have low sensitivity to temperature changes consistent with their low mass-balance amplitude. However, very large changes in mass balance could occur on arctic island glaciers if the sea ice surrounding the arctic islands were reduced so that the climate of the arctic islands becomes more maritime.

The Deep Ice Sheet Coring (DISC) drill, developed by Ice Coring and Drilling Services (ICDS) under contract with the US National Science Foundation, is an electromechanical drill designed to take 122 mm diameter ice cores to depths of 4000 m. The conceptual design of the DISC drill was developed in 2002/03 based on science requirements written by K. Taylor and the United States ice-coring community and on engineering performance objectives. Detailed design of the drill began in June 2003. Special attention was paid to building safety into the design and operation of the drill system. The drill was designed and manufactured by a team of engineers and technicians from the University of Wisconsin–Madison and various subcontractors with assistance from the science community, the European ice-drilling community and polar logistical support organizations. ICDS successfully tested the drill in Greenland in 2006 and will continue its development to meet the science objectives of the West Antarctic Ice Sheet Divide Ice Core Project.

Given the pronounced atmospheric warming recorded in recent decades on the Antarctic Peninsula (AP), knowledge of glacier mass balance in this region is especially important for assessing the impact of climatic warming on ice masses. ‘Glaciar Bahía del Diablo’ (GBD) on Vega Island, northeastern AP, is a glacier that terminates on land, so its mass balance is directly linked to climate. GBD is a polythermal outlet glacier, 14.3 km2 in area with an accumulation–area ratio of 0.39. Increased ablation rates and glacier thinning motivated us to select GBD as a test site for mass-balance studies within the region. Calculations based on the stratigraphic annual method yielded a mean annual loss of 0.32 mw.e. a–1 for the annual net mass balance (bn) between 1999 and 2003. A strong correlation was observed between bn and mean summer temperatures, confirming that GBD is highly sensitive to climate. The study of GBD aims at establishing a suitable reference database for ice–climate studies in a region of dramatic changes in Antarctica.

Crystal size in polar ice caps increases with depth from the snow surface down to several hundred meters. Data on crystal growth in isothermal polar snow and ice show the same linear relationship between the size of crystals and their age. This paper reviews the mechanical behavior of polar ice which exhibits grain growth. Grain boundary migration associated with grain growth appears to be an efficient accomodation process for grain boundary sliding and dislocation glide. For grain growth to occur, strain energy must always be lower than the free energy of boundaries. The sintering of ice particles in polar firn is energized by the pressure due to the overburden of snow. Dislocation creep must be taken into account to explain the densification rate in the intermediate and final stage Constants of power law creep should depend on the crystal growth rate.

Ship and iceberg drifts, along with data from modern satellite-tracked drifting buoys, portray generally northward flow in the southwest Ross Sea. Less is known, however, about the ocean variability in this region. Here we use Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) imagery to describe a cyclonically rotating gyre in Terra Nova Bay, Antarctica (75° S, 165° E). The image sequence is taken from an exceptionally clear, calm period during winter 1998. Surface currents, derived from tracking drifting ice with a maximum cross-correlation algorithm, were found to be ∼ 20 to 30 cm s−1 Based on scaling arguments, the observed currents appear to be best explained as an oceanic response to a rapidly changing, offshore, katabatic windjet.

Over a distance of 150 km inland across British Columbia, glaciation level (altitudinal threshold for glacier generation) rises north-eastward from 1800 m near Jervis Inlet, to 2800m near Lillooet on Fraser River. The methods of Østrem (1966b) are revised for more detailed work from air photographs; inclusion of small but active glaciers gives a glaciation level some 200 m below Østrem’s from 1:250 000 maps, or 110 m below that from 1:50 000 maps.

Mountains which rise slightly above the altitudinal threshold invariably support glaciers only on their northerly slopes. Mountain crests need to be some 300 m higher before they support glaciers on most slopes: this defines an “all-sided” glaciation level. Since summit heights vary from 2500 to 2900 m through most of the transect considered here, east- and west-facing glacier sources are found mainly in the coastal half; south-facing sources are rare outside icefields.

For particular mountain ranges bounded by valleys and low passes, the aspects (azimuths) of glacier sources can be summarised by vector analysis. The higher the range rises above glaciation level, the more widespread the aspects represented and the weaker the resultant vector strength. Strengths as high as 90% are observed on landward ranges with a relatively sunny, continental climate, while 20-60% is found for coastal ranges where cloudiness reduces slope variations in incident solar radiation. Vector mean aspects throughout are close to north.

Perennial lee drifts on icefields show that wind directions during and immediately after snowfalls are from the south or from south-south-west. Together with orographic details of the glaciation level, this suggests that snow-bearing winds come from the south rather than the west. These winds reinforce radiation contrasts, giving north-south asymmetry of glacier aspect even near the coast.

Measurements of the chemical composition of the snow pits at Murododaira (2450m a.s.l.), Mount Tateyama, near the coast of the Japan Sea in central Japan, were performed each spring from 2005 through 2008. The mean concentrations of nssSO42– and NO3– are higher than those in snowpack in the 1990s. The pH and nssCa2+ were usually high in the upper parts of 2–3m of snow deposited in the spring, when Asian dust (Kosa) particles are frequently transported. High concentrations of nssSO42– were detected in both the spring and winter layers. The high-nssCa2+ layers usually contained high concentrations of nssSO42–. The results show that not only Kosa particles but also air pollutants might have been transported long-range from the continent of Asia. The concentrations of peroxides were high in the new snow (precipitation particles) and granular snow (coarse grain, melt forms) layers. The peroxide concentrations in the snow layers were negatively correlated with the nssCa2+ concentrations. High peroxide concentrations may be preserved in granular snow layers having low concentrations of nssCa2+.

This paper presents a method for deriving the snowline altitude using a combined analysis of terrain elevation and multispectral Advanced Wide Field Sensor (AWiFS) data from the RESOURCESAT-1 satellite, launched by India on 17 October 2003. AWiFS is a unique instrument capable of acquiring imagery of the world repeatedly every 5 days with very high radiometric resolution. It provides a wide swath width, which is very useful for snow-cover mapping. Snowline altitude is a good indicator of snow coverage. Snowline altitude for the period from October 2004 to June 2005, and from October 2006 to June 2007, is determined for the Baspa Basin, which is located in the Kinnaur district of Himachal Pradesh, India. It is observed that snowline altitude is generally higher during the year 2006/07 than during 2004/05, except in December 2006 and March 2007. The results obtained with the analysis presented here are validated using available meteorological data and are found to be satisfactory. This thus establishes a method that can be applied to other terrains and over longer periods of time within the coverage of the AWiFS sensor data.

In order to improve understanding of spatial and temporal variations of stable isotopes in atmospheric precipitation, snow cover and glacier meltwater in different regions of China, samples were collected for isotopic analysis in four areas: Yulong mountain, Yunnan Himalaya (temperate-glacier area); Samdain Kangsang mountain, Nyainqêntanglha Shan (subpolar-glacier area); the headwater area of the Ürümqi river, Tien Shan (subpolar-glacier area); and Muztag mountain, Pamirs (polar-glacier area). Sampling was undertaken in both summer and winter between 2000 and 2003. The δ18O values show a ‘temperature–altitude effect’ in new winter snow on Yulong mountain, reflecting the condensation and fractionation processes associated with the winter monsoon, but a different, more complex pattern in residual snow deposited during the summer monsoon; this old snow is influenced by the ‘precipitation amount effect’, solar radiation and evaporation, and the water content of the snowpack. The summer precipitation at Samdain Kangsang mountain is associated with the summer monsoon. There is a marked precipitation amount effect during the long passage of the southwest/India monsoon from the distant moisture source to Samdain Kangsang mountain, and the summer precipitation is strongly depleted of the heavy isotope. Above 6000 m, the high radiation flux causes much evaporation from the snow surface. The associated 1 8O enrichment of the snow is reflected in a ‘reverse altitude effect’. The δ18O values in the summer snowpack of the Tien Shan and Muztag mountain decrease with increasing altitude and decreasing air temperature, indicating a temperature–altitude effect. Post-depositional processes cause isotopic changes during the transformation of snow/firn/ice to meltwater; the effects are much stronger at temperate than at polar glaciers. Moreover, changes in the isotopic signal at both temperate and polar glaciers can result from evaporation, sublimation, ablation and drifting.

Several recent studies have suggested that much of the winter-time Antarctic ice is thin (<0.3m). The presence of extensive areas of thin ice has a significant effect on ocean-atmosphere energy exchange. This is investigated using the Maykut (1978) thin-ice energy-budget model in a study for typical September Antarctic ice and climatic conditions. To study the sensitivity of turbulent heat loss to ice concentrations, the Maykut model is combined with an empirical parameterization for the turbulent fluxes from leads (Andreas, 1980) which takes account of the non-linear relationship between heat loss and lead width (or ice concentration). In this one-dimensional sensitivity study, a constant floe-size is assumed, and ice-concentration variations are simulated by changing the width of the leads between floes. The modelled results, for the floe size considered, indicate that at 80% ice concentration the turbulent heat loss through the thin ice component can be greater than that from leads. As concentration decreases, however, the fractional loss through the ice, and, hence, the ice-thickness distribution, becomes less significant. For the concentrations lower than 50%, there is little change in turbulent loss with further decrease in ice cover, as the atmosphere effectively “sees” open ocean.

The jökulhlaups in the Yarkant (Yarkand) River are usually caused by the sudden drainage of glacier-dammed lakes through rapidly expanding subglacial channels. The lakes are dammed by Keyajir (Kyagar) Glacier and Telamukanli (Singye) Glacier which are situated in the upper reaches of the Keleqin (Shaksgam) River. In recent years the glaciers have become thinner, and the glacier-dammed lakes and their outbursts have become smaller.

The Sea-Ice Model Intercomparison Project (SIMIP) is part of the activities of the Sea Ice-Ocean Modeling Panel (SIOM) of the Arctic Climate System Study (WMO) (ACSYS) that aims to determine the optimal sea-ice model for climate simulations. This investigation is focused on the dynamics of sea ice. A hierarchy of four sea-ice rheologies is applied, including a viscous-plastic rheology, a cavitating-fluid model, a compressible Newtonian fluid, and a simple scheme with a step-function stoppage for ice drift.

For comparison, the same grid, land boundaries and forcing fields are applied to all models. Atmospheric forcing for a 7 year period is obtained from the European Centre for Medium-Range Weather Forecasts (UK) (ECMWF analyses), while occanic forcing consists of annual mean geostrophic currents and heal fluxes into a fixed mixed layer. Daily buoy-drift data monitored by the International Arctic Buoy Program (IABP) and ice thicknesses at the North Pole from submarine upward-looking sonar are available as verification data. The daily drift statistics for separate regions and seasons contribute to an error function showing significant differences between the models. Additionally, Fram Strait ice exports predicted by the different models are investigated. The ice export of the viscous-plastic model amounts to 0.11 Sv. when it is optimized to the mean daily buoy velocities and the observed North Pole ice thicknesses. The cavitating-fluid model yields a very similar Fram Strait outflow, but underestimates the North Pole ice thickness. The two other dynamic schemes predict unrealistically large ice thicknesses in the central Arctic region, while Fram Strait ice exports are too low.

Since the mid-1970s radio-echo soundings have been conducted on Iceland's temperate glaciers. Since then, low-frequency radar technology has furthered the study of most of the island's ice caps. Their masses and volumes have been quantified and detailed subglacial topographic maps produced which demarcate glacial drainage basins and identify subglacial lakes and volcanoes. Even internal tephra layers have been charted. The resulting data have been used to force and validate models of past and future glacier evolution. Many practical applications in glacier hydrology have come into being, including hydropower management, road and bridge planning and the prediction of catastrophic flood paths from subglacial eruption sites. Finally, emerging landscapes can now be foreseen in places where glaciers may soon disappear. These achievements would not have been possible without the advances in RES technology.

The new approaches in absorption X-ray microtomography allow snow-volume image acquisition in the cm3 range without destroying snow structure, and make it possible to perform micromechanical studies with the real geometry. The main objective of this paper is to introduce the development of a new three-dimensional (3-D) geometry modeling and finite-element analysis simulation package adapted to these scales. These new code modules and procedures are briefly described using an isothermal metamorphism snow experiment (–2°C, 3 months).This sample of aged snow (3.375mm3; 3003 voxels) allows simulation of a simple hypothetical uniaxial compressive stress experiment. The constitutive equations, boundary conditions, basic assumptions and the result showing the stress field over the 3-D data are discussed. The first qualitative results show a maximum stress of 6–9MPa in some small bonds, showing the potential of these codes to simulate the micromechanical behavior of complex materials.