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Abstract: This paper presents data concerning recent (1990–2007) surface morphological and ice-dynamical changes on the Tasman Glacier, New Zealand. We use remote-sensing data to derive rates of lake growth, glacier velocities and rates of glacier surface lowering. Between 1990 and 2007, the glacier terminus receded ~3.5 km and a large ice-contact proglacial lake developed behind the outwash head. By 2007 the lake area was ~6 km2 and had replaced the majority of the lowermost 4 km of the glacier tongue. There is evidence that lake growth is proceeding at increasing rates — the lake area doubled between 2000 and 2007 alone. Measured horizontal glacier velocities decline from 150 m a−1 in the upper glacier catchment to almost zero at the glacier terminus and there is a consequent down-glacier increase in surface debris cover. Surface debris mapping shows that a large catastrophic rockfall onto the glacier surface in 1991 is still evident as a series of arcuate debris ridges below the Hochstetter icefall. Calculated glacier surface lowering is most clearly pronounced around the terminal area of the glacier tongue, with down-wasting rates of 4.2±1.4 m a−1 in areas adjacent to the lateral moraine ridges outside of the current lake extent. Surface lowering rates of approximately 1.9±1.4 m a−1 are common in the upper areas of the glacier. Calculations of future lake expansion are dependent on accurate bathymetric and bed topography surveys, but published data indicate that a further 8–10 km of the glacier is susceptible to calving and further lake development in the future. [Copyright &y& Elsevier]

Abstract: Ice-free areas Antarctica reveal a multi-million year history of landscape evolution, but most attention up to now has focused on the Transantarctic Mountains. The Amery Oasis in the northern Prince Charles Mountains borders the Lambert Glacier—Amery Ice Shelf System that drains 1millionkm2 of the East Antarctic Ice Sheet, and therefore provides a record of fluctuations of both local and regional ice since the ice sheet first formed in early Oligocene time. This glacial record has been deciphered by (i) geomorphological mapping from aerial photographs and on the ground, (ii) documenting the relationship between thick well-dated, uplifted glaciomarine strata and the underlying palaeolandscape, (iii) examining surficial sediment facies, and (iv) surface-exposure dating using 10Be and 26Al. The SE Amery Oasis records at least 10 million years of landscape evolution beginning with a pre-late Miocene phase of glacial erosion, followed by deposition of glaciomarine strata of the Battye Glacier Formation (Pagodroma Group) in late Miocene time. A wet-based ice sheet next expanded over the SE Amery Oasis, following which deposition of the glaciomarine Pliocene Bardin Bluffs Formation (Pagodroma Group) took place. Both formations were uplifted; by at least 500 and 200m, respectively. Their tops are characterised by geomorphological surfaces upon which intensive periglacial activity took place. Higher-level bedrock areas were subjected to deep weathering and tor-formation. Early Pleistocene time was characterised by expansion of a cold-based ice sheet across the whole area, but it left little more than patches of sandy gravel and erratic blocks. Late Pleistocene expansion of local ice (the Battye Glacier) saw deposition of moraine-mound complexes on low ground around Radok Lake and ice-dammed lake phenomena. Subglacial drainage of the lake escaped to the east exhuming the sediment-filled gorges. Holocene landscape modification has been relatively superficial. Overall, the landscape of the Amery Oasis evolved primarily under the influence of wet-based (probably polythermal) glaciers in Miocene and Pliocene times, whereas the Quaternary Period was characterised mainly by cold-based glaciers that had comparatively little impact on the landscape. [Copyright &y& Elsevier]

Glacier recession in response to climate warming has resulted in an increase in the size and number of glacial lakes. Glacial lakes are an important focus for research as they impact water resources, glacier mass balance, and some produce catastrophic glacial lake outburst floods (GLOFs). Glaciers in Peru have retreated and thinned in recent decades, prompting the need for monitoring of ice- and water-bodies across the cordilleras. These monitoring efforts have been greatly facilitated by the availability of satellite imagery. However, knowledge gaps remain, particularly in relation to the formation, temporal evolution, and catastrophic drainage of glacial lakes. In this paper we address this gap by producing the most current and detailed glacial lake inventory in Peru and provide a set of reproducible methods that can be applied consistently for different time periods, and for other mountainous regions. The new lake inventory presented includes a total of 4557 glacial lakes covering a total area of 328.85 km2. In addition to detailing lake distribution and extent, the inventory includes other metrics, such as dam type and volume, which are important for GLOF hazard assessments. Analysis of these metrics showed that the majority of glacial lakes are detached from current glaciers (97%) and are classified as either embedded (i.e. bedrock dammed; ~64% of all lakes) or (moraine) dammed (~28% of all lakes) lakes. We also found that lake size varies with dam type; with dammed lakes tending to have larger areas than embedded lakes. The inventory presented provides an unparalleled view of the current state of glacial lakes in Peru and represents an important first step towards (1) improved understanding of glacial lakes and their topographic and morphological characteristics and (2) assessing risk associated with GLOFs. • We present a new contemporary and comprehensive lake inventory for the Peruvian Cordilleras • We provide a set of inventorying methods to facilitate replicability in other locations, globally • We record and analyse a number of important lake metrics for understanding GLOF hazards • We estimate lake volume in all glaciated cordilleras and compare these with other studies [ABSTRACT FROM AUTHOR]