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We exploit the attribute analysis of GPR data to analyze the different EM responses of the ice of two alpine glaciers. We focus on frequency-related attributes to identify zones with higher attenuation of EM signal, which could be further related to higher water content and higher electrical conductivity. We succeeded in associating the scattering facies to warm ice zones of the Marmolada glacier, further linked to the thickness of the snow cover, and to a layer of mixed debris and ice of the Eastern Gran Zebrù glacier. Moreover, we conducted automated diffraction hyperbolas analyses to gain insight into the basal thermal conditions and glaciological facies.

A 10-year-long evolution of ice thickness and volume of the Marmolada glacier is presented. Quantitative measurements have been performed by using two different Ground Penetrating Radar (GPR) datasets. A ground-based survey using two different ground-coupled systems equipped with 100 MHz and 35 MHz antennas was performed in 2004. In 2015 the dataset was collected by using a helicopter-borne step frequency GPR equipped with a 100 MHz antenna. Through a critical discussion of the two different methodologies, we show how both approaches are useful to estimate the ice volume within a glacier, as well as its morphological characteristics and changes with time, even if datasets are acquired in different periods of the year. The observed 2004–2014 ice volume reduction of the Marmolada glacier is equal to about 30%, while the area covered by ice decreased by about 22%. The glacier is now splitted in several separated units. It is very likely that the fragmentation of the Marmolada glacier observed in the period 2004–2014 was accelerated due to irregular karst topography. By applying the observed 2004–2014 ice-melting trend for the future although the Marmolada glacier might behave slightly differently compared to glaciers on non-karstic terrains owing to dominant vertical subglacial drainage, it will likely disappear by the year 2050. Only few isolated very small and thin ice patches will eventually survive due to avalanche feeding and shading at the foot of the north-facing cliffs.

Accepted manuscript version, licensed CC BY-NC-ND 4.0. Abrasion and quarrying are significant processes of subglacial erosion for ice masses in direct contact with hard substrates, yet their relative efficacy and spatio-temporal variability is unclear. Here, we investigate the glacial impact of these processes on a 70 m by 60 m bedrock surface at Moel Ysgyfarnogod in the Rhinog Mountains, Wales, using a combination of high-resolution digital photographs, analysis of a Digital Terrain Model derived from an Unmanned Aerial Vehicle survey, and regional ice sheet modelling. We map and analyze the distribution of grooved and striated surfaces, abraded surfaces, quarried blocks and open fractures in addition to the orientation of pre-existing bedrock fractures and joints. The grooves and striations are orientated in a single, consistent direction across the bedrock surfaces related to regional ice flow during the Late Pleistocene. Abraded and smoothed bedrock dominates the proximal edges of the bedrock outcrop and quarrying prevails on the distal edges of the bedrock outcrop, which are dominated by detached and partially detached blocks. We propose these blocks were removed during the final stages of the last glacial cycle when subglacial meltwater was plentiful in this otherwise predominantly frozen subglacial setting. A minimum estimate of 2000 m3 displaced material at this site implies that subglacial quarrying would have been an important erosional process during final stages of deglaciation.

Glaciokarst is a landscape which combines karst features and hydrology as well as inherited glacial features. It is a result of glaciation upon a karst geomorphological system. The relationship between glaciers and karst is rather poorly known and inadequately recognized. This research focuses on three distinct karst areas along the Adriatic coast in the southern Dinaric Alps that were affected by the Quaternary glaciations. An insight into specific glaciokarst processes and surface features was provided through the study of the areas of the Lovcen, Orjen and Velež Mountains. A glaciokarst geomorphology is in general well preserved due to the prevailing vertically oriented chemical denudation following de-glaciation and almost the entire absence of other surface processes. Typical glacial erosional features are combined by a variety of depressions which are the result of a karstic drainage of sub-glacial waters. The majority of glacial deposits occur as extensive lateral-terminal moraine complexes, which are often dissected by smaller breach-lobe moraines on the external side of the ridge. Those moraine complexes are likely to be a product of several glacial events, which is supported by complex depositional structures. According to the type of glacial depositional features, the glaciers in the study areas were likely to have characteristics of moraine-dammed glaciers. Due to vertical drainage ice-marginal fluvial processes were unable to evacuate sediment. Fluvial transport between glacial and pro-glacial systems in karst areas is inefficient. Nevertheless, some sediment from the glacier margin is washed away by the pro-glacial streams, filling the karst depressions and forming piedmont-type poljes. Copyright © 2015 John Wiley & Sons, Ltd.

The southeastern European Alps represent the spot where mean annual precipitation is at its highest in the entire Alpine chain. Accordingly, the glacial evolution here might have a different spatial and chronological pattern if compared with other alpine areas. This paper discusses geomorphological evidence of three glacial stages from the Krnica Valley in the Julian Alps of Slovenia, and is the first step towards a comprehensive palaeoglaciological studies in this alpine sector. Very well-preserved glacial landforms in the Upper Krnica Valley allowed the reconstruction of glacier surface topographies and corresponding equilibrium line altitudes (ELAs) by means of field-based geomorphological and sedimentological data and by using geospatial analysis. The uppermost frontal moraines belong to the Little Ice Age (LIA) and the corresponding ELA is estimated at 1973 m a.s.l. Other two stages with the ELA depressed by 50 m and 161 m compared to the LIA ELA, suggest early Holocene and Younger Dryas ages of the palaeoglaciers, respectively. This assumption ensues from absolute age datings and related ELA depressions observed elsewhere in the European Alps. The presence of buried ice under the debris in the Krnica cirque, imaged through geophysical investigations, point to peculiar microclimatic conditions able to preserve relict glacier ice. This is favoured by the recursive presence of snow on the ground caused by the extreme summer shading and the significant winter snow-recharge triggered by snowblow and avalanche feeding. The possible evolution of such relict ice under the ongoing climate warming is also discussed.

The study of Pleistocene glaciations in the Dinaric Alps began at the end of the 19th century. Since then, the interpretation of glaciation in this area has not seen much study until the beginning of the 21st century, when a few modern geomorphological studies with numerical dating and equilibrium line altitude (ELA) reconstructions were carried out in the SE part of the Dinaric Alps (where Mount Lovcen is situated). The morphology of Mount Lovcen consists of a karst landscape modified by glacial processes. This paper presents geomorphological evidence of glaciations on Mount Lovcen, along with a reconstruction of paleoglacier dimensions and estimations of the paleo-equilibrium line altitude. Mapping of glacial landforms on Mount Lovcen revealed at least two different glacial events. Only limited patches of older glacial deposits were identified, and therefore the reconstruction of glacier dimensions and ELA were only performed for the younger glaciation. This glacier extended over an area of at least 39.9 km 2 and reached a maximum thickness of about 290 m. The regional ELA for the Mount Lovcen glaciers was calculated as 1259 m.

Trnovski gozd is a high karst plateau situated in the Dinaric Mountains of western Slovenia which was modified by glacial action in the Pleistocene. With our research we concluded that slopes with northern exposure and the footslope of the highest ridge of Golaki had an glacier up to 180 m thick with an area of 4.8 km2. Several outlet glaciers were found to have been drifting over a steep escarpment from the plateau to the valleys of Belca, Trebuša and on the Hudo polje plateau. There was no evidence of glaciation on southern exposed slopes. The equilibrium line altitude was established via the accumulation-area ratio method on an elevation of 1240 m. Trnovski gozd je visoka kraška planota na dinarskem krasu zahodne Slovenije, ki so jov pleistocenu preoblikovali tudi ledeniški procesi. Ugotovili smo, da je severna pobočja in podnožje najvišjega osrednjega grebena Golaki pokrival ledenik s površino 4,8 km2 in največjo debelino okoli 180 m. V več odtočnih ledenikih je padal preko strme reliefne stopnje v dolini Belce in Trebuše ter na Hudo polje. Prisojna pobočja Golakov niso bila poledenela. Z metodama deleža akumulacijskega dela ledenika ter zgornje meje bočnih moren smo izračunali ravnovesno mejo ledenikov na višini 1240 m.

Biokovo massif is situated in the coastal part of the Dinaric Mountains in Croatia. Detailed morphographic and morphometric analysis of the highest parts of the massif were used to determine the extent and characteristics of Late Pleistocene glaciation. The reconstruction of glaciers and calculations of equilibrium line altitude (ELA) were carried out. Our research revealed that on the north-eastern side of the highest peak Sveti Jure two cirque glaciers with an overall area of 1 km 2 were formed and their ELA was 1515 m a.s.l.

Rock glaciers and protalus ramparts are characteristic landforms of the periglacial domain often used as markers for the occurrence of permafrost in mountain terrains. As such, relict rock glaciers can be used for paleoclimate reconstructions. We present here the first previously unreported rock glacier inventory of the south-eastern Alps (including the north-eastern-most region of Italy and Slovenia), interpreted from high resolution orthophotos and a high resolution digital terrain model interpolated from airborne laser scanning (LiDAR). We mapped 53 rock glaciers covering a total area of 3.45 km(2). The majority of rock glaciers are classified as relict and distributed between 1708 and 1846 m a.s.l. with slope ranging between 19 and 27. In addition to rock glaciers we observed 66 protalus (pronival) ramparts, having median elevation of 1913 m a.s.l. and covering 0.48 km(2). More than half of the inventoried protalus ramparts are located in the more maritime area of the Alps with higher precipitation compared to the location of rock glaciers. Using paleoclimate reconstruction based on the 1981-2010 climatological record of the area, we infer that the rock glaciers formed during one of the dry and cold periods of the late Pleistocene and early Holocene. Possible evolution of the active pronival forms observed in the most maritime area of this alpine sector is also discussed. (C) 2016 Elsevier B.V. All rights reserved.

Gomance is a piedmont karst polje in the northern Dinaric Alps presenting geomorphological and sedimentological evidence of past glaciation. During the Pleistocene the polje was situated at the edge of the Snežnik and Gorski Kotar ice fields from where two outlet glaciers reached Gomance. The morphogenesis of the polje was reconstructed by means of geomorphological mapping, sedimentological studies, and ground penetrating radar (GPR) measurements, supported by hand-drillings. With GPR an almost entirely buried moraine system was also imaged and mapped, crucial in reconstructing the polje history. The depression was karstified and well drained without any surface streams before the Last Glaciation. When the glacier front reached the depression, the entire floor became covered by glacial and outwash deposits. Surface runoff dominated over karst drainage in a large part of the polje, particularly where distal outwash deposits with low effective porosity functioned as an aquitard. These deposits diverted surface drainage toward the lowest edge of the polje, which functioned as a ponor front along the entire length. The outwash system of the Gomance polje was active during the Last Glaciation as suggested by radiocarbon-dated outwash deposits.

The Stara Galicica Mountain was highly reshaped by glacial processes during the Pleis-tocene. Based on the detailed morphographical mapping of glacial features, the extent of glaciation was determined as being far larger than described in previous references. The in-ner part of the massif was covered with an ice-cap from where outlet glaciers were fowing out. On the basis of morphometrical analysis of glacial features, the altitude of the glacier equilibrium line during the Last Glacial Maximum was established at 1840 m a.s.l.

Snežnik and Gorski Kotar are mountainous areas in the Northern Dinaric Alps. We investigated this remote and densely forested area on the border between Slovenia and Croatia between 2011 and 2014. The result of the fieldwork campaign is a 1:30,000 geomorphological map covering almost 600 km2. The study area mainly consists of Mesozoic age limestone and dolostone. Karstified carbonate lithology results in almost the complete absence of surface run-off and a dominance of typical karst morphology. The extensive karstified area was modified by Quaternary glaciations; therefore, the recent landscape is characterized as a glaciokarst. The focus of the presented map is to provide a basis for further research of Quaternary glaciations in the areas of Snežnik and Gorski Kotar. Along with the map, we propose a legend for glaciokarst landscape mapping.

Rock glaciers in the southeastern Alps of Slovenia and Italy have been mapped in detail using high resolution digital elevation model and orthophotos, supported by field-based observations. A total of 52 rock glaciers with an area of 3.40 km2 have been delineated on a rock glacier map, divided in 18 sections at a scale of 1:15,000. Several geometrical parameters of rock glaciers have been calculated and their activity degree has been inferred. 90% of rock glaciers have been classified as relict, while the rest are assumed to be of uncertain activity and might still contain some ice. The volumetric ice content and water volume equivalent of the studied rock glaciers for the period of their activity has been calculated to 0.055 ± 0.011 km3 and 0.049 ± 0.010 km3, respectively, which is very close to the ice volume of glaciers reconstructed for this area during the little ice age to 0.069 km3.