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The Last Glacial Maximum (LGM) is a global event that occurred 26 to 21 ka BP and was characterized by lower temperatures (3 to 6 °C globally) and different precipitation regimes. The environment was marked by extended glaciers which released a large set of morphologies as the systems of well-preserved moraines in the alpine foreland that testify the advanced phases of the alpine glaciers during the LGM. Mountain glaciers, quickly responding to temperature and precipitation variations, are considered excellent indicators of climate change. Here we focus on the European Alps and attempt to unveil the physical processes that sustained the glacier extent during the LGM using a multiple regional climate model (RCM) nesting approach. Toward this goal, we completed and intercompared two high-resolution (12 km) RCM simulations, one for the steady-state LGM standard (21 ka BP) and one for pre-industrial (PI) conditions. We also calculated the LGM and PI environmental equilibrium line altitude (envELA) for the whole Alpine chain starting from physically-based summer temperature a total annual precipitation. Precipitation and temperature patterns show good consistency with proxy records and other RCM studies. In particular, our results present a predominance of convection over stratiform precipitation during summer, as well as increased southwesterly stratiform precipitation in the southern alpine region compared to the PI. Frequent summer snowfall, extending to low elevations, where caused by this precipitation pattern, along with lower temperatures, and led to a substantial drop in the ELA. Our model-based evaluation of the LGM ELA showed unprecedented consistency with the estimated LGM Alpine glacier reconstructions, further proving the great potential of this method for paleoclimate applications.

Slovenia is situated at the border of the European Alps, the Pannonian Basin and the Dinaric Alps. Over 90 % of its surface is covered by sedimentary rocks, of which nearly half are carbonate rocks such as limestone and dolomite. During the Quaternary extensive glaciations occurred here which reshaped the surface and formed typical glacial landforms such as moraines, glacial troughs and circular hollows called glacial cirques. Glacial cirques typically form at higher elevations underneath mountain ridges. They are often characterized by an arcuate planform and concave profile. The morphogenesis of glacial cirques is tied to the subglacial erosion of a rotational glacial flow which involves the plucking of underlying bedrock and abrasion of the cirque floor with the entrained sediment. The analysis of morphometric and morphogenetic properties of glacial cirques allows for the interpretation of the type, duration and intensity of glaciation as well as the paleoclimate during the time of the formation of glacial cirques.Glacial cirques in Slovenia have yet to be systematically studied. The first step towards this is the identification and classification of glacial cirques. The identification was performed manually using key morphographic (arcuate planform, location near ridges) and morphometric (slope, curvature) parameters of glacial cirques and using the LIDAR surface data with a spatial resolution of 1x1 m from the Slovenian Environment Agency. In the first stage 129 potential glacial cirques were identified in the three Slovenian mountain ranges (the Julian Alps, the Kamnik-Savinja Alps and the Karavanke Mountains). Relevant morphometric data (slopes, curvature, dimensions, aspect, size, circularity…) were then calculated for the identified landforms. Using hierarchical clustering methods (Ward, Gower, minimum linkage, complete linkage…) and morphometric data multiple quantitative classifications of glacial cirques were made.The obtained classification of glacial cirques in Slovenia was objective, statistically supported and founded on quantitative data and as such is potentially applicable to populations of glacial cirques elsewhere. There is still an unsolved dilemma regarding the objectivity and reliability of the manual identification of potential glacial cirques, which could possibly be solved by implementing machine learning. This could lead to a completely automated and impartial identification of glacial cirques.

On a global scale, inventories and databases are gaining value and there is a demand for openly accessible and reusable data. Here presented GIS database of glacial geomorphological evidence is a compilation of all available glacial and other relevant data in the South-Eastern Alps and the Northern Dinaric Mountains in Slovenia, Italy and Croatia. The database contains the following elements: glacial landforms (e.g., moraines, cirques, erratic fields, kame terraces), non-glacial landforms relevant for the interpretation of the glacial environment (e.g., alluvial fans, alluvial terraces, rock glaciers, protalus ramparts, talus cones), outcrop locations, geochronological data, and data on geophysical exploration. The accompanying attribute tables contains some basic information for each feature, such as type and description of a landform, assumed age, reference, etc. In the first step of database creation, the data were digitised, georeferenced (if not already done by the authors themselves) and cited accordingly. In the second step, the input data were revised in the field and topographically adjusted using a high-resolution lidar-based digital elevation model. The GIS database of glacial geomorphological data was used to develop the web map viewer, which also displays empirically reconstructed ice limits for different time spans during the last glacial cycle (130-0 ka). The data stored in the GIS database is available as ESRI shapefile format. Both the GIS database and the map viewer are open access. Disseminating the results of past and ongoing studies on glacial geomorphological evidence in the Alps-Dinarides junction will improve the availability and accessibility of data, build on previous findings and potentially prevent unnecessary repetition of work already done. Improved accessibility of data also offers greater potential for further research in large-scale studies in the area. This work was funded by the Past climate change and glaciation at the Alps-Dinarides junction project (J1-2479) supported by the Slovenian Research Agency.

Although several types of glacial landforms and deposits were described from different parts of the Croatian Dinarides, up to date there are no quantitative glacial chronological data. Here we present the first cosmogenic 36Cl glacial chronology from the Southern Velebit Mt. from a moraine complex known as the Rujanska Kosa. We sampled four limestone boulders and used 20 mm ka−1 erosion corrected ages, as the study area is composed of well-karstified carbonate deposits and located in one of the highest precipitation regions of Europe. The inner Rujanska Kosa ridge yielded an age of 20.7 ± 2.2 ka for the retreat of glaciers in that part of Velebit Mt. A slightly older age was measured from the outer ridge on the left-lateral part of the Rujanska Kosa, which dates back to 22.7 ± 2.7 ka ago. Whilst the ages between inner and outer ridges overlap within error, we can place an age difference between the two moraines to be between 0 and 6.9 ka, supported by the geomorphic evidence that the latter is older. Although we could not perform any geomorphological work higher up in the Rujno paleo-ice field due to the remnant minefields, our results may indicate a Late Pleistocene (i.e. la st glacial maximum) retreat of ice from the Southern Velebit Mt. Despite the small number of valid samples, acquired age data on glacial landforms in Southern Velebit Mt. are in accordance with ages from several other Mediterranean mountain ranges.

The Taurus Mountain Range extends parallel to the Mediterranean coast of Turkey. It hosts lofty mountains (>3000 m above sea level, a.s.l.) carved by glaciers in the Late Pleistocene. Despite the recent studies in Anatolia, Mt. Davraz (2635 m a.s.l.) has not been studied in detail and its glacial chronology was lacking. This study presents our first findings of the glacial history, origin and geochronology of Mt. Davraz, which is located SW of Eğirdir Lake (915 m a.s.l.), 100 km north of Antalya city. Tectonics, karstification, glaciation, and periglaciation have led a distinctive geomorphology of the area. The main landscape of the area is predominantly shaped by paleoglaciers. Cirques are the dominant glacial erosional landforms, and most of them were developed on the northern slopes of Mt. Davraz. Based on the topographical limitations, cirque paleoglaciers could not to transformed into valley glaciers. Although it is one of the lowest mountains in the Taurus Mountain Range, it has a large hummocky field with an area of about 3 km2 on the northern slope. It was developed by a paleo-ice cap. There is also a smaller hummocky field deformed by a rock glacier advancements on the E-NE slopes of the mountain. In order to understand the timing of paleoglaciations, we obtained 6 cosmogenic 36Cl surface exposure ages from the moraine boulders on hummocky field. Based on the preliminary results, Mt. Davraz hummocky field yielded sequential retreat history; the eastern hummocky field deposited their moraines at 21.7 ± 1.5 ka ago, while the western hummocky field at 17.7 ± 1.2 ka ago. Our results show that the glaciers started to retreat by the Last Glacial Maximum (LGM) and continued to the earlier stages of Late-glacial. This work was supported by TÜBİTAK-118Y052 project.

The highest parts of the Dinaric Mountains along the eastern Adriatic coast of the southern Europe, known for their typical Mediterranean karst-dominated landscape and very humid climate, were glaciated during the Late Pleistocene. Palaeo-piedmont type glaciers that originated from Cvrsnica Mountain (2226 m a.s.l.; above sea level) in Bosnia and Herzegovina deposited hummocky, lateral and terminal moraines into the Blidinje Polje. We constrained the timing of the largest recognized glacier extent on Svinjaca and Glavice piedmont glaciers by applying the cosmogenic 36Cl surface exposure dating method on twelve boulder samples collected from lateral, terminal and hummocky moraines. Using 40 mm ka–1 bedrock erosion rate due to high precipitation rates, we obtained 36Cl ages of Last Glacial Maximum (LGM; 22.7 ± 3.8 ka) from the hummocky moraines, and Younger Dryas (13.2 ± 1.8 ka) from the lateral moraine in Svinjaca area. The amphitheater shaped terminal moraine in Glavice area also yielded a Younger Dryas (13.5 ± 1.8 ka) age within the error margins. Our results provide a new dataset, and present a relevant contribution towards a better understanding of the glacial chronologies of the Dinaric Mountains. Because our boulder ages reflect complex exhumation and denudation histories, future work is needed to better understand these processes and their influence on the cosmogenic exposure dating approach in a karstic landscape.

Glaciokarst depressions are major glacigenic depocenters in the Dinaric mountain karst areas and often store important information about the timing and nature of glacial processes and paraglacial sediment reworking. This study focuses on Praprotna draga, which is one of the largest glaciokarst depressions in the Snežnik Mountain (Dinaric karst), with an area of ~3.4 km2 and a maximum depth of 140 m. The western slopes of the depression are characterized by undulated moraine morphology and alluvial fans are filling its entire floor. We present the results on the thickness, origin and age of the sediment infill using a complementary geomorphological, sedimentological, geophysical and dating approach. Distribution of moraines point to two glacial advances that were associated with two main alluvial fan aggradation phases recognized using the electrical resistivity tomography measurements. The youngest alluvial deposits were sampled for cosmogenic 36Cl analysis using amalgamated carbonate pebbles. The depth profile of 36Cl concentrations suggests an age of 12.3 ± 1.7 ka when assuming a likely denudation rate of 20 mm ka−1. Since the existence of the Younger Dryas glaciers in the study area is climatically difficult to explain, we tentatively propose that the youngest alluvial deposition in Praprotna draga took place after the glacier retreat during the paraglacial period. Our findings suggest that the time window of paraglacial adjustment in the Snežnik Mountain was brief and likely conditioned by quick recolonization with vegetation and inefficient surface runoff on deglaciated karst terrain.

The distribution of rock glaciers is often used to investigate the occurrence of permafrost in mountain areas and to understand their climate and paleoclimate evolution. This requires the creation of regional and global inventories capable of discriminating active and relict landforms in order to forecast the presence or absence of ice in the ground. In this paper, geomorphological, geophysical and microclimatic surveys are performed on a rock glacier of the Carnic Alps (Eastern European Alps). In the classification currently used for implementing regional inventories of permafrost evidence in the Alps, this rock glacier would be defined as relict. However the geophysical, climatological and geomorphological results indicate that internal ice is widespread in large portions of the rock glacier. These are generally interpreted as ice in pore spaces and local ice lenses, probably without layers of massive ice. Moreover the occurrence of ice during the maximum thawing season at depths

Very small glaciers (&lt, 0.5 km2) account for more than 80% of the total number of glaciers and more than 15% of the total glacier area in the European Alps. This study seeks to better understand the impact of extreme snowfall events on the resilience of very small glaciers and ice patches in the southeastern European Alps, an area with the highest mean annual precipitation in the entire Alpine chain. Mean annual precipitation here is up to 3300 mm water equivalent, and the winter snow accumulation is approximately 6.80 m at 1800 m asl averaged over the period 1979–2018. As a consequence, very small glaciers and ice/firn patches are still present in this area at rather low altitudes (1830–2340 m). We performed repeated geodetic mass balance measurements on 14 ice bodies during the period 2006–2018 and the results show an increase greater than 10% increase in ice volume over this period. This is in accordance with several extreme winter snow accumulations in the 2000s, promoting a positive mass balance in the following years. The long-term evolution of these very small glaciers and ice bodies matches well with changes in mean temperature of the ablation season linked to variability of Atlantic Multidecadal Oscillation. Nevertheless, the recent behaviour of such residual ice masses in this area where orographic precipitation represents an important component of weather amplification is somehow different to most of the Alps. We analysed synoptic meteorological conditions leading to the exceptional snowy winters in the 2000s, which appear to be related to the influence and modification of atmospheric planetary waves and Arctic Amplification, with further positive feedbacks due to change in local sea surface temperature and its interactions with low level flows and the orography. Although further summer warming is expected in the next decades, we conclude that modification of storm tracks and more frequent occurrence of extreme snowfall events during winter are crucial in ensuring the resilience of small glacial remnants in maritime alpine sectors.

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 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.

Blidinje is tectonically derived lowland in the Dinaric Alps within Bosnia and Herzegovina. It is surrounded by Vran, Čvrsnica and Čabulja Mountains. The Blidinje study area is predominantly built of carbonates, where karst, fluvial and glacial geomorphological systems interact. We present a 1:25,000 geomorphological map covering a 100 km2 with an elevation range of 1200–1900 m. The map results from a combination of a fieldwork mapping, interpretation of orthophotos and an analysis of a digital elevation model. This map presents a distribution of landforms and sediments associated with the past and present karst, glacial and fluvial processes, such as different varieties of karst depressions, conical hills, erosional gullies, alluvial fans and large amphitheatre-like moraines. The focus of the presented map is to assist ongoing studies in this part of the Dinaric Alps that seek to understand the dynamics of former glaciers and associated palaeoclimate.

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.