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The presence of supraglacial debris on glaciers in the Himalaya-Karakoram affects the ablation rate of these glaciers and their response to climatic change. To understand how supraglacial debris distribution and associated surface features vary spatially and temporally, geomorphological mapping was undertaken on Baltoro Glacier, Karakoram, for three time-separated images between 2001–2012. Debris is supplied to the glacier system through frequent but small landslides at the glacier margin that form lateral and medial moraines and less frequent but higher volume rockfall events which are more lobate and often discontinuous in form. Debris on the glacier surface is identified as a series of distinct lithological units which merge downglacier of the convergence area between the Godwin-Austen and Baltoro South tributary glaciers. Debris distribution varies as a result of complex interaction between tributary glaciers and the main glacier tongue, complicated further by surge events on some tributary glaciers. Glacier flow dynamics mainly controls the evolution of a supraglacial debris layer. Identifying such spatial variability in debris rock type and temporal variability in debris distribution has implications for glacier ablation rate, affecting glacier surface energy balance. Accordingly, spatial and temporal variation in supraglacial debris should be considered when determining mass balance for these glaciers through time. [ABSTRACT FROM PUBLISHER]

Longitudinal ice-surface structures in the Antarctic Ice Sheet can be traced continuously down-ice for distances of up to 1200 km. A map of the distribution of ~3600 of these features, compiled from satellite images, shows that they mirror the location of fast-flowing glaciers and ice streams that are dominated by basal sliding rates above tens of metres per annum and are strongly guided by subglacial topography. Longitudinal ice-surface structures dominate regions of converging flow, where ice flow is subject to non-coaxial strain and simple shear. They can be traced continuously through crevasse fields and through blue-ice areas, indicating that they represent the surface manifestation of a three-dimensional structure, interpreted as foliation. Flow lines are linear and undeformed for all major flow units described here in the Antarctic Ice Sheet except for the Kamb Ice Stream and the Institute and Möller Ice Stream areas, where areas of flow perturbation are evident. Parcels of ice along individual flow paths on the Lambert Glacier, Recovery Glacier, Byrd Glacier and Pine Island Glacier may reside in the glacier system for ~2500 to 18 500 years. Although it is unclear how long it takes for these features to form and decay, we infer that the major ice-flow configuration of the ice sheet may have remained largely unchanged for the last few hundred years, and possibly even longer. This conclusion has implications for our understanding of the long-term landscape evolution of Antarctica, including large-scale patterns of glacial erosion and deposition. [ABSTRACT FROM AUTHOR]

The article presents a case study on the rates of glacier reduction in Southern and Northern Patagonia Icefield in Andes within 140 years. The research provides information on glacier descriptors, length and area changes, and yearly grades of change. They conclude the shrinkage are dominated by smaller land-terminating glaciers in the north, and smaller fringing glaciers in the south.

The article presents the study which examined the glacier acceleration and elevation lowering at the James Ross Island and the Antarctic Peninsula following the collapse of the Prince Gustav Ice Shelf in the Antarctic Peninsula in 1995. In the study, the ice surface elevation changes obtained from the Röhss Glacier via the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation models (DEM). The data obtained in the study include the surface elevation changes, glacier surface flow velocity and ice thickness.

The article presents a model of the flow, fracture and stability of the Larsen C ice shelf in the Antarctic Peninsula, combining physically based ice-shelf flow modelling and linear elastic fracture mechanics. It describes the recent hypothesis that mechanical heterogeneity acts to stabilize the ice shelf and validates the modelled flow against satellite and in situ geophysical field data. The article concluded that the Larsen C ice shelf is stable in its current dynamic regime however, weakening of the elongated marine ice zones could lead to its acceleration.

The article discusses a study on the surface structure and stability of the Larsen C ice shelf in the Antarctic Peninsula. The structural and glaciological description and an analysis of the features of the surface of Larsen C ice shelf were taken from the satellite images. Ice shelves cover more than 40 percent of the Antarctic continent but suffered collapse events due to atmospheric and oceanic warming. The study used the results of detailed structural glaciological mapping of the ice shelf such as the data on the changes in the entire system of the Larsen C ice-shelf for the period from 1963 to 2003 to 2004, and information of the changes in its surface of from 2002 to 2007. The study found that boundaries between the flow units showed rift terminations with soft ice.