Unlike other glacier fluctuations during the Holocene, the glacier advances during the Little Ice Age (LIA) occurred widely across many glaciated regions in both hemispheres. To understand the climatic mechanisms driving this widespread phenomenon, it is essential to determine whether the LIA was a truly global event or if it was confined to specific regions.
Exploring cosmogenic-nuclide-dated moraine chronologies offers a powerful method to address this question. This approach leverages several key advantages:
- Measurements of cosmogenic nuclides in moraine boulders enable direct dating of moraine deposition, marking the end of a glacier's advance.
- Advances in cosmogenic nuclide dating techniques have made them sufficiently precise to identify individual glacier advances within the Late Holocene, including those associated with the LIA.
- An increasing number of Late Holocene moraine records, including those from the LIA, are now available from many regions around the world, allowing for a more comprehensive analysis.
In this contribution, we first present examples of well-resolved cosmogenic nuclide records of Late Holocene and LIA moraines. We then analyze a global dataset of cosmogenic-nuclide-dated moraine boulders to unravel the spatial patterns of LIA occurrence across different regions. Finally, we discuss potential climate forcings that could explain these patterns.
How to cite: Schimmelpfennig, I. and Jomelli, V.: Was the Little Ice Age global? The cosmogenic perspective, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13072, https://doi.org/10.5194/egusphere-egu25-13072, 2025.
Reconstructing interactions between past glaciers, climate and topography over millennial timescales is crucial for predicting their dynamics under future climate change. Abrupt climate oscillations during the Last Glacial Maximum (~24 - 19 ka) and the Last Deglaciation (~19 - 11.7 ka) led to the growth, fluctuations and decay of large ice sheets and smaller mountain glaciers in Europe but the Southern Carpathians (Romania) have not been examined widely in this context.
Here, we present the first application of a palaeoclimate-driven, dynamic numerical ice model (Parallel Ice Sheet Model) to the Southern Carpathians. Focused on the Retezat-Godeanu mountain group, our aim is to simulate the extent, style, dynamics and climatic/topographic drivers of former glaciers in the region. Using a range of static and dynamically evolving simulations, we found that 1) the model could adequately grow plateau icefields and ice domes that match well with geomorphological evidence for ice extent in the region; 2) a significantly colder (-5°C…-8°C temperature deviations from the present) and drier (45%....15% of modern precipitation amounts) climate was required to grow palaeoglaciers to their maximum extents; 3) the model adds glaciological context to the geomorphological data by identifying where ice was slow- vs fast-moving, cold- vs warm-based, and aids interpretation of geological samples potentially containing inherited 10Be cosmogenic nuclides. Finally, by simulating a more muted response of glaciers to palaeoclimate during the Younger Dryas (12.9 - 11.7 ka), we find that it is possible that the Southern Carpathians could have supported limited ice at that time, suggesting where geological evidence for such ice could be sought.
How to cite: Balaban, C. I., Jamieson, S. S. R., Roberts, D. H., Evans, D. J. A., and Ruszkiczay-Rüdiger, Z.: Reconstructing Late Pleistocene glacier dynamics in the Southern Carpathians (Romania) with the Parallel Ice Sheet Model, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12876, https://doi.org/10.5194/egusphere-egu25-12876, 2025.
Glaciations of the Pleistocene have left a global imprint, expanding from polar plains to equatorial mountains on all continents. This glacial record has been systematically researched for nearly two centuries. However, its diversity, as well as fieldwork logistics, ice-flow modelling challenges and paleoclimate unknowns have often constrained paleoglacier studies to remain regional.
Here, we present a global, 30 arcsec resolution map of temperature change needed to initiate glacier growth, hereafter glacial inception threshold. Using downscaled climatologies from CHELSA-2.1 and CHELSA-W5E5 over the period 1981–2010, a positive-degree-day snow accumulation and melt model is applied globally with temperature anomalies ranging from +5 to -20 K to compute the glacial inception threshold.
Glacial inception accelerates for temperature anomalies below -3 K in North America and Asia, and below -5 K in Europe and South America, but remains limited to localized highlands for all tested temperatures in Africa and Oceania. The inception threshold is locally sensitive to the choice of input climate dataset, particularly in Central Asia and Patagonia. Under 1981–2010 conditions, mountain glaciers form at altitudes following a camel curve peaking at 7 km in the tropics, and lowering to about 1 km along the polar circles. An inception threshold of 0 represents contemporaneous accumulation limits, and indeed this pattern is comparable to modelled equilibrium lines for all glaciers on Earth from the Open Global Glacier Model (OGGM) and the Global Glacier Evolution Model (GloGEM).
Under Last Glacial Maximum climate from the Paleoclimate Modelling Intercomparison Project Phase 4 (PMIP4), glacial inception areas expand to lower elevations. Validation against paleo-equilibrium line reconstructions from small glaciers in the Cordilleras shows good agreement in the mid-latitudes but underpredicted glaciation in the tropics. Further comparison to global glacial extents and cosmogenic isotope dates show that our glacial inception threshold map reproduces many known glacier and ice-sheet inception centres, while also hinting at potentially undocumented mountain glaciations. While our map does not account for glacier expansion from ice flow, we hope it will help identify potential targets for future field and modelling studies, and provide a foundation towards global paleoglacier research.
How to cite: Seguinot, J., Van Cappellen, M., Legrain, E., Aguayo, R., Van Tricht, L., Born, A., and Zekollari, H.: Global glacial inception threshold from positive degree-day modelling, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12185, https://doi.org/10.5194/egusphere-egu25-12185, 2025.
The glacial history of the eastern Himalayas has remained undocumented compared to its western and central regions. In this study, we present 63 Be-10 exposure ages from glacial deposits in the Dri Valley, situated at the eastern extremity of the Himalayas, to reconstruct the first Pleistocene glaciation history of the ~900 km long Arunachal Himalayas. The most extensive glaciation occurred before ~48 ka (and possibly earlier than ~58 ka), when the (inferred) trunk glacier reached 100 km in length and descended to around 1500 to 1300 m above sea level (a.s.l) – among the lowest elevations recorded for glaciers in the Himalayan-Tibetan Orogen. The main valley glacier remained substantial during the Last (Global) Glacial Maximum (LGM) and had a length of ~76 km and terminated around 1680 m a.s.l.
Despite dense forest cover, paraglacial and postglacial erosion obscuring (prominent) glacial landforms in the Dri Valley, an integrated approach combining geomorphological evidence and high-resolution satellite imagery with cosmogenic-based geochronological data has enabled a detailed reconstruction of its Pleistocene glaciation. Glacial deposits covering elevations from 3700 to 1600 m a.s.l were subdivided based on morphostratigraphy, revealing four periods of postglacial exposure dating to ≥58 ka, ~48 ka, ~19 ka and ~13 ka. The results indicate that the Dri Valley cirques (elevations ~3700 to ~3800 m a.s.l) became ice free between ~14 – 13 ka. Reconstruction of the cirque glacier yields an equilibrium line altitude (ELA) of approximately 3750 m, corresponding to a ∆ELA of ~900 m compared to today which is among the largest ELA depressions in the Himalayas for this period (~14 ka to present).
Our findings reveal that Late Quaternary glaciation in the Dri Valley was primarily temperature-driven, influenced by long-term orbital forcing. With approximately 90% of the region’s abundant annual precipitation today occurring in summer, a positive mass balance for the Dri glacier is maintained up to a temperature-sensitive threshold. Beyond this threshold, even minimal warming would have caused glacier retreat (or collapse) due to a larger percentage of the summer precipitation falling as rain rather than snow, reducing the glacier’s accumulation. This is reflected in the termination of Dri Valley glacial phases correlating with known regional warm periods. This study offers critical insights into the climate-glacier interactions in the understudied eastern Himalayas and enhances our understanding of broader Himalayan-Tibetan palaeoclimate.
How to cite: Nitundil, S., Stone, A., Hughes, P., Darvill, C., Fink, D., Tomkins, M., and Simon, K.: 10Be evidence for extensive, low-elevation Late Pleistocene glaciation in far eastern (Arunachal) Himalayas - timing and palaeoclimate reconstruction , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12398, https://doi.org/10.5194/egusphere-egu25-12398, 2025.
During the Last Glacial Maximum (LGM; 27.5-23.3 ka), the British Irish Ice Sheet (BIIS) and Welsh Ice Cap (WIC) jostled for position around the margins of North Wales, documented by complex moraines that demonstrate the push and pull interchange between ice margins. The relative timing of thinning and retreat of the WIC thereafter has important implications for our understanding of these complex ice-marginal systems. The deglacial landscape documents numerous moraine successions in the valleys, as well as in the cirques. Until now many cirque moraines have been assumed to be Younger Dryas in age, although this has rarely been tested using cosmogenic exposure dating. Here, we present a suite of thirty-two new Cl-36 exposure ages from glacially transported boulders that span the length of Dee Valley, Northeast Wales. We interpret the timing of lateral retreat and vertical thinning with samples that span from the palaeo-ice centre in the Arenig mountains, to the proposed ice margin at the Welsh/English borderland. We also test the validity of hypothesised Younger Dryas cirque glaciers by dating boulder samples directly atop suspected inner and outer moraines.
The Dee Valley has a complex cosmogenic isotope signature showing numerous pre-LGM exposure ages, reflecting the reworking of pre-exposed material down valley. Nevertheless, the majority of exposure ages indicate rapid post-LGM disintegration of ice through the Dee Valley. Across the uplands of Wales, this would have resulted in a shift to a fragmentary pattern of ice coverage. Cl-36 exposure ages from cirque moraines and high-level plateaux and ridges also confirm the upland area of Arenig Fawr (854 m)—previously suggested as a former centre of the WIC—was ice-free soon after the LGM and remained ice-free thereafter. This is in contrast to other parts of North Wales where alpine-style valley glaciers persisted until around 15 ka, with some cirques occupied by glaciers during the Younger Dryas. The implication is that the deglacial history of Wales is more complex than previously thought with significant variations through space and time. It is also evident from our study that not all cirque moraines in Northeast Wales are Younger Dryas in age, with some considerably older and reflecting earlier glacier retreat.
How to cite: Thomas, O., Hughes, P., Darvill, C., and Ryan, P.: Rapid thinning, disintegration and fragmentation of the Welsh Ice Cap during the last deglaciation., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12125, https://doi.org/10.5194/egusphere-egu25-12125, 2025.
Several studies have been attempted in the rain-shadow zone of the NW Indian Trans-Himalaya to delineate quaternary spatio-temporal palaeo-glacial extents. The glaciers in this region are influenced by two major climatic systems; i.e. Western Disturbances (WD) and Indian Summer Monsoon (ISM) with spatio-temporal variable intensities from north to south respectively. In case of the transitional climatic zones, on the southern fringe of the Trans-Himalaya where ISM and WD both have been instrumental in controlling the glacial activity, there has been wide range of study conducted in Lahaul and Zanskar. Spiti, further E-SE, though lacks palaeo-glacial studies due to poor glacial deposit preservation and dominant fluvial recycling of sediments, despite glaciers currently supplying over 50% of the basin's water. Although, modern glaciation in Spiti is limited to high altitudes above 5000m, features like glacial striations, U-shaped valleys, and sparsely preserved palaeo-glacial deposits in various parts of Spiti indicate that glaciers once extended to much lower elevations in the past.
Our work focused on spatio-temporally constraining these palaeo-glaciations within Spiti. Our study involved detailed geomorphological and sedimentological studies using litho-facies and clast-macrofabric analyses to identify the palaeoglacial deposits and past glacial extensions within the basin. The identified deposits were chronologically constrained using luminescence dating in order to understand temporal glacial landscape evolution within Spiti. Our study identified the dominant LGM influence on the glaciation on the S-SW side of Spiti trunk channel towards southern fringe of Trans-Himalaya between ~29 ka to ~15 ka. Whereas the palaeoglacial signatures in the northern direction of trunk channel of Spiti towards Ladakh are majorly constrained between ~100 ka – ~45 ka. Our findings indicate that paraglacial processes were the primary driver of landscape evolution in the upper Spiti basin during the late Quaternary, leading to the basin's headward expansion.
How to cite: Sharma, U., Ray, Y., and Sangode, S. J.: Unravelling the quaternary palaeoglacial archives from the Trans-Himalaya: Evidence from geomorphological, sedimentological studies and luminescence dating in Spiti basin, NW Himalaya, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-250, https://doi.org/10.5194/egusphere-egu25-250, 2025.
The majority of glaciers in North America reached their maximum Holocene downvalley positions during the Little Ice Age (1300-1850 CE), and in most cases, this expansion also destroyed earlier evidence of glacier activity. Substantial retreat in the 20th and early 21st centuries exposed bedrock that fronts many glaciers that may record early-to-mid Holocene exposure and later burial by ice which can be elucidated using multiple-nuclide cosmogenic surface exposure dating. Furthermore, cores of bedrock allow the measurement of cosmogenic nuclide depth profiles to better constrain potential exposure and burial histories. We collected four bedrock surface samples for 10Be and 14C surface exposure dating and shallow (<0.6 m depth) bedrock cores from Vintage Peak, in the southern Coast Mountains of British Columbia, Canada. We apply a Monte Carlo approach to generate combinations of exposure and burial duration that can explain our data. We found that Vintage Peak became uncovered by the Cordilleran Ice Sheet between 14.5 and 9.7 ka, though higher reaches on Vintage Peak retained ice until 10-12 ka before retreating to smaller than modern positions. Glaciers on Vintage Peak advanced within 100 m of late Holocene maximum positions around 4-6 ka. Poorly constrained subglacial erosion rates, possible inheritance, and variable mass shielding complicate our ability to more robustly interpret bedrock cosmogenic surface exposure histories. Nine 10Be ages on late Holocene moraines reveal that glaciers reached their greatest Holocene extents ca. 1300 CE. Our results agree with other regional glacier records and demonstrate the utility of surface exposure dating applied to deglaciated bedrock as a technique to help construct a record of Holocene glacier activity where organic material associated with glacier expansions may be absent or poorly-preserved. Further work to increase exposure/burial history modelling complexity may help to better constrain complex exposure histories in glaciated alpine areas.
How to cite: Hawkins, A., Goehring, B., and Menounos, B.: Terrestrial Cosmogenic Nuclide bedrock depth profiles used to infer changes in Holocene glacier cover, Vintage Peak, Southern Coast Mountains, British Columbia, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7338, https://doi.org/10.5194/egusphere-egu25-7338, 2025.
Stretching from ~33ºS to ~46ºS, the Southern Volcanic Zone (SVZ) in the Andes constitutes one the most continuous glaciated volcanic regions along the midlatitudes. Here, most headwaters are on active volcanoes, with glaciers in a notable variety of forms, including valley glaciers, ice aprons, mountain glaciers, and crater glaciers. Furthermore, ubiquitous glacial landforms attest for larger ice coverage in the past. Building from earlier foundational case studies, since 2015 we have developed a multidisciplinary and multiscale research program focusing on the glacierized SVZ landscape including, but not limited to, past, present, and future climate patterns, geomorphology, glacier changes, and mountain (socio)hydrology. Here, we summarize this research endeavor and present the main findings to date, aiming to integrate our case studies into a cohesive regional perspective. Individual efforts of several research groups working across different sections of the SVZ have converged towards a more cohesive program under years of networking, funding acquisition, and mentoring of students and early career researchers. Together, we have applied a diverse range of methods to study the components of the glacial SVZ landscape, including instrumental hydroclimatic observations, numerical modeling, geomorphological mapping, radionuclide and optically stimulated luminescence dating, geodetic measurements, remote sensing processing, and geospatial techniques. Analysis of instrumental observations and high-resolution climate modeling indicates North-South and East-West temperature and precipitation contrasts associated with uniquely complex topographic dynamics. Geomorphology analysis reveals that current topographic complexity has been shaped by a mixture of Pleistocene to Holocene volcanism, reverse faulting along the western Andean front and transpressive faulting along the intrarc, and long-term glacier erosion. These processes possibly explain remarkable patterns of glacier sensitivity to climate change, as extensive glacier accumulation zones develop along the northern (33ºS to 36°S) and southern (42ºS to 46°S) sections, unlike intermediate SVZ latitudes where mountaintops rarely rise above the free-atmosphere freezing level height. Dating of moraines preserved around some SVZ glaciers points to several Holocene regional advances since ~4000 years BP, although some anomalously high and steep moraine complexes, glacio-volcanic landforms, as well as significant differences in glacier size across short distances, point to potentially non-climatic forcings that remain poorly understood. Remote sensing and glaciological mass balance, coupled with model simulations, predict uninterrupted clean ice losses during the 21st century, even under the most optimistic climate warming mitigation scenarios. The dynamics of debris-covered areas, however, remain insufficiently quantified. Studies using water isotopes from a partially glacierized catchment located at 38.9ºS, reveal diverse mountain hydrology, where groundwater and ponds are key contributors to streamflow. However, glacier melt seems disproportionately important relative to the ice surface coverage. In this presentation, we aim to demonstrate how these case studies point to interlinked dynamics that have not been traditionally studied in the mountain sciences, impacting interpretations of long-term glacier changes and their hydrological consequences. Finally, we outline challenges and opportunities ahead, including new research priorities to advance interdisciplinary characterization of the glaciated SVZ. This work highlights the potential of converging diverse research agendas towards a common goal of unveiling interactions among mountain ice, water and climate.
How to cite: Fernández, A., Lillo, M., Somos-Valenzuela, M., Rivera, D., Jaque, E., Huaico, A., Arndt, J. E., Farías, D., Herrera, M., Navas, S., Lizama, E., Cortés, J., Oviedo, J. A., McPhee, J., Mejías, A., Xie, H., Mahmoud, H., Mark, B., Owen, L., and Stansell, N.: Mountain ice, water and climate along the Andean Southern Volcanic Zone: A decade (and counting!) unfolding a unique landscape, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7387, https://doi.org/10.5194/egusphere-egu25-7387, 2025.
Mountain regions are essential for understanding Earth’s climatic history, as their glacial cycles have shaped landscapes, ecosystems, and regional climates during the Quaternary, leaving behind palaeoglacier records that reveal past climate dynamics. Particularly, mountain glaciers respond sensitively to climatic changes, making them crucial for understanding regional and local climate variations. This higher sensitivity is evident once the maximum glacial extent in mountains often occurred outside the global Last Glacial Maximum (26–19 kyr BP). However, existing global palaeoglacier databases (e.g. Ehlers et al, 2011) have not been updated to incorporate palaeoglaciers reconstructed in the last decade.
We present a new open-access global geodatabase of mountain glacier extents for the LGM. This synthesis integrates ice-extent reconstructions from 224 studies across 271 mountain ranges globally, standardising over 14,700 individual glacier reconstructions into a geodatabase covering the period 57-14 kyr BP. We implemented a mountain range classification system, compiled metadata from each publication, and linked each reconstruction to its original sources. This effort has updated the state of knowledge in 157 mountain ranges, added 9,450 new reconstructions, and identified a gap in research in 114 mountain ranges.
Our geodatabase is a powerful resource for investigating regional past climate variability, mountain landscape evolution, and ecological impacts of glaciations. It provides glacier masks for validating glacier modelling and offers spatial boundaries for paleoecological reconstructions of mountain ecosystems. Furthermore, it identifies understudied regions, guiding future work in Quaternary science. We anticipate releasing the database soon with the corresponding publication and website, along with detailed methodology and guidelines for further use.
How to cite: Lima, A., Margold, M., L.C. Hughes, A., Dulfer, H., Barr, I., Rentier, E., Laabs, B., and G.A. Flantua, S.: Global geodatabase of mountain glacier extents at the Last Glacial Maximum , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20104, https://doi.org/10.5194/egusphere-egu25-20104, 2025.
The New Zealand Alps offers excellent opportunities to investigate the nature and timing of past climate variability during the Holocene. Some glacial geochronological studies have been published focussing on this key site for the mid-latitudinal southern hemisphere, but a considerable degree of uncertainty and differences in individual chronologies have emerged. Specific glacial characteristics of this climatically and geomorphologically dynamic mountain region coupled with different analytical dating methodologies need to be correctly quantified, combined, and evaluated to better understand the complexities of New Zealand’s more recent glacial history.
In this study we applied 10Be cosmogenic radionuclide dating (CRN; n = 54) and Schmidt-hammer exposure-age dating (SHD; n = 42,000) to obtain surface exposure-ages from moraine boulders on Holocene glacier forelands in the eastern Aoraki/Mt.Cook National Park (Classen Glacier, Godley Glacier, Murchison Glacier and its tributaries) and the Arrowsmith Range (Ashburton Glacier, Cameron Glacier). SHD was performed utilising both regional SHD age-calibration equations based on published independent CRN ages and locally-adjusted equations based on our new CRN data and additional chronological information. This multi-proxy approach was combined with detailed geomorphological mapping and analysis to tackle the regionally specific 'geomorphological uncertainty' potentially interfering with subsequent interpretation of chronological data. We directed considerable effort to carefully define the glacial geomorphological context to guide our sampling strategies to ensure robust and reliable results.
On the foreland of Classen Glacier we establish a new geomorphologically reliable moraine site for a significant Mid-Holocene advance at 5 - 6 ka. At Godley and Murchison Glaciers, new precise 10Be ages reveal the outermost Holocene moraines date from the 'Little Ice Age'. Our new SHD and CRN data coupled with geomorphological mapping shows that Late Holocene moraines which pre-date the 'Little Ice Age', occur at two glaciers in this area. In contrast, SHD and CRN data from Ashburton Glacier constrain the outermost moraine ridge to strong glacial activity during the Early Holocene. The number of advances unambiguously represented by moraines is, however, smaller than previously reported from nearby Cameron Glacier. At both glaciers, moraines representing the maximum 'Little Ice Age' glacier advance give SHD-age estimates that predate respective moraines in Aoraki/Mt.Cook National Park by more than 150 years. With no confirmed evidence for multiple advances during the Early Holocene in Aoraki/Mt.Cook National Park, these significant differences indicate that amalgamation of Holocene glacier chronologies from both areas is not justified. The morphostratigraphic configuration and individual morphology of moraines on the glacier forelands is complex and in some cases may be explained by excessive supraglacial debris caused by large mass movement events. This situation seems prevalent across the forelands and probably typical for the entire Southern Alps.
Our new Holocene glacier chronology shows considerable discrepancy to previously published studies, in particular regarding the number and timing of Late Holocene glacier advances. Further refinement of the Holocene glacier history for the Southern Alps constitutes a significant challenge requiring a more detailed understanding in the spatial variability of individual glaciers of the region.
How to cite: Winkler, S., Fink, D., Baldwin, S., and Simon, K.: An Early Holocene to 'Little Ice Age' glacier chronology for New Zealand's Southern Alps - challenges, improvements, and implications, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1979, https://doi.org/10.5194/egusphere-egu25-1979, 2025.
The geochronological dating of glacial landforms, particularly terminal and lateral moraines, is invaluable for determining the extent and timing of past glaciation and for reconstructing the magnitude and rate of past climate changes. In the central Himalayas, well-dated glacial geomorphological records have constrained the last glacial cycle around much of the Mount Everest region. However, the eastern Ama Drime Range remains comparatively less constrained.
Here, we present a detailed chronology dataset from the Marine Oxygen Isotope Stage (MIS) 3 (~29–57 ka) and subsequent deglaciation, focusing on the Zongcuo Valley and Riwu Valley in Ama Drime Range, China (28°6′N, 87°4′E). This analysis is based on 19 beryllium-10 (10Be) surface-exposure ages from terminal moraine systems within these valleys. We reconstructed the extent and thickness of Last Glacial Maximum (LGM) glaciers through geomorphological mapping and a flowline-based glacial model, PalaeoIce. Additionally, we applied the accumulation area ratio (AAR) method to estimate the equilibrium-line altitude (ELA) for each stage identified.
Our results reveal that the Zongcuo Glacier and Riwu Glacier reached their maximum extents at 39.9 ± 3.3 ka, coinciding with MIS 3. By 25.2 ± 2.9 ka, the Zongcuo Glacier had retreated slightly up-valley. This retreat is evidenced by well-preserved moraine landforms from the LGM, which greatly facilitated our reconstruction of the ancient Zongcuo Glacier. At its maximum, the glacier covered an area of 26.3 km², had a maximum thickness of 343 m, and an ELA ~560 m lower than present (~5260 m a.s.l.), which we used as a baseline for comparison.
By 15.8 ± 1.5 ka, corresponding to the Late Glacial period, the glacier had retreated ~2 km up-valley, indicating at least a ~20% reduction in glacier length relative to its LGM extent. The glacier area decreased to 19.6 km² (a ~25% reduction), with a maximum thickness of 316 m (a ~25% reduction). The ELA was ~480 m lower than present (~5350 m a.s.l.).
By 860 ± 160 years ago, during the Little Ice Age (LIA), the glacier had retreated ~7 km up-valley from its LGM position, representing at least a ~50% reduction in glacier length. The glacier area had decreased to 6.8 km² (~65% reduction), and the maximum thickness was 140 m (~59% reduction) compared to the LGM. The ELA was ~390 m lower than present (~5440 m a.s.l.).
Using a temperature lapse rate estimate, these ELA anomalies suggest that the local mean annual temperature was ~2.1°C colder than the present (1981–2010) at 860 ± 160 years ago, ~2.6°C colder at 15.8 ± 1.5 ka, and ~3.0°C colder at 25.2 ± 2.9 ka, assuming no significant change in precipitation.This study provides critical insights into the response of glaciers to climate change over the past 40 ka in the southern Tibetan Plateau.
How to cite: Liu, F., Liu, G., Chen, M., and Hou, G.: Cosmogenic 10Be Constraints on Deglacial Snowline Rise Since MIS 3 in the Central Himalayas, China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6753, https://doi.org/10.5194/egusphere-egu25-6753, 2025.
This study presents the glacial geomorphology and chronology of the Gongba Mountain area in Daocheng (28°58'N, 100°23'E), located in the southeastern sector of the Tibetan Plateau, an important region influenced by significant climatic oscillations during the Quaternary. Utilizing advanced remote sensing technologies, we generate a high-resolution Digital Elevation Model (DEM) with the aid of an Uncrewed Aerial Vehicle (UAV) to map the glacial geomorphology of this sector. We supplement our DEM mapping with satellite imagery (SPOT, ArcGIS Basemap), Google Earth Pro and field surveys to reveal a range of landforms reflecting the area's glacial history. Meanwhile, within this region, we also collected and statistically analysed the 10Be exposure ages of 13 boulders from 4 moraine ridges. These data are of great significance for understanding the timing of glacier advance and retreat in the Gongba Mountain area during the Quaternary.
This is the first map of such high resolution for the Daocheng area. Within a 32 square kilometer region, we have meticulously mapped 270 moraine ridges at the meter scale. Additionally, we precisely identified and delineated glaciolacustrine, glaciofluvial and post-glacial landforms (e.g., outwash plains, glaciofluvial deposits, shorelines, kettle holes and deltas) and bedrock features influenced by subglacial and periglacial processes (ice-scoured bedrock and weathered bedrock). We integrated the geomorphological characteristics of the moraine ridges in the study area with the 10Be results. The exposure-ages of the four sampled moraine ridges from south to north are 14.8 ± 1.0 ka, 19.3 ± 1.2 ka, 30.4 ± 1.9 ka, and 83.5 ± 5.1ka, respectively. These data reveal the existence of large-scale glacier advances during MIS 5 and MIS 3 in the study area, provide evidence of glacier advance during the global Last Glacial Maximum (LGM), and indicate small-scale glacial fluctuations with a lack of significant moraine deposits during the lateglacial period.
By establishing a foundational dataset for glacial geomorphology in this region and providing corresponding chronological data with good consistency, our work serves as a critical resource for future research on paleoclimate and environmental changes, providing a longer-term context for ongoing and future impacts of climate change on glacial dynamics in high-altitude environments.
How to cite: Luo, W., Cooper, E.-L., Yang, W., Tielidze, L., Zhang, X., Mackintosh, A., and Liu, G.: Glacial geomorphology and chronology of the Gongba Mountain area, Daocheng, southeast Tibetan Plateau, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14401, https://doi.org/10.5194/egusphere-egu25-14401, 2025.
Glacial forms, which are products of the cold periods of the Quaternary, are found in many parts of Türkiye. Being a mountainous country, the high parts of Türkiye, which are above the permanent snow line, were occupied by glaciers many times during the Quaternary and some glaciers have survived to the present day despite rapid melting in recent decades. In the parts where the glaciers have completely melted, the shapes of glacial geomorphology have preserved their freshness to a great extent. Although Türkiye's current glacier inventory is considered to be complete, there are still glaciated areas of different sizes that have not yet been identified in the literature. One such area is Mount Kısır, located just west of Lake Çıldır in the far northeast of Türkiye. Glaciated sites there have not been reported in the literature and there is a lack of geomorphological, climatological and chronological information about these sites. Mount Kısır (40°57′ N, 43°04′ E) is a mass of Pliocene andesites with a peak of 3197 m, 35 km southeast of Ardahan. We used topographic maps, UAVs and detailed field studies to map the glacial morphology on Mount Kısır. This established 20 cirques, 10 glacial valleys, prominent lateral moraines on their slopes and frontal moraines descending to 2200 m a.s.l. The main ridge runs north from Mount Kısır with more cirques and glacial valleys on the east slope than on the west. The former glaciers were up to 250 m thick and the longest were 11.8 km in Guvercin Valley and 12 km in Kose Valley, both on the east slope. The next goal of this study is to obtain cosmogenic dating of the glacial deposits of Mount Kısır and to contribute to the modelling of the Quaternary climatic conditions of Türkiye by establishing the relationship between these data and local climatic conditions.
This study was supported by TUBITAK project number 122Y360
How to cite: Bayrakdar, C., Keserci, F., Çılğın, Z., and Evans, I. S.: Geomorphological and morphometric characteristics of former glaciers on Mt. Kısır, Northeast Turkey, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1194, https://doi.org/10.5194/egusphere-egu25-1194, 2025.
Geomorphological evidence of cold environments in the Drakensberg, southern Africa, has long been debated. Previous work, based on geomorphological, micromorphology and modelling techniques has suggested glacial conditions above ca. 3200 m a.s.l. However, this has been challenged due to the unclear glacial genesis of geomorphological features. This work aims to provide new evidence of past glacial and periglacial conditions in the Drakensberg.
Our aim is addressed by mapping a geomorphological sketch (1:25000) near the Sani Pass, Drakensberg, based on a 0.5 m resolution Digital Surface Model and an orthomosaic derived from Pléiades satellite imagery, and validated by field reconnaissance work. Specifically, the areas of the Sehonghong plateau, the upper reaches of the KwaNtuba cutback, and the Mangaung catchment, were investigated with several uncrewed aerial vehicle surveys for a detailed geomorphological mapping (1:5000). Finally, we applied Schmidt-Hammer exposure-age dating (SHD) and collected sixteen samples for Cosmic-Ray Exposure (CRE) dating from well-preserved features suggesting glacial and periglacial dynamics, which are currently being processed.
The Sehonghong plateau is located adjacent to the Great Escarpment, between 3400 and 3290 m a.s.l., and has gentle NE-facing slopes. The highest terrain is characterised by the widespread occurrence of weathered surfaces. The bedrock surfaces are littered with highly weathered and eroded ‘shattered’ debris, which provides the source for block fields and which have been reworked by periglacial processes, as evidenced by large sorted stone circles. At the plateau floor, degraded earth hummocky terrain and turf exfoliation areas are examples of wetland degradation. The different landforms suggest wind and seasonal frost conditions are the major geomorphic agents.
The KwaNtuba cutback faces ESE from 3350 to 2870 m a.s.l and encompasses steep slopes along the SW-NE-oriented Great Escarpment. The cutback headwall is shaped by an amphitheatric feature with 220 m high (3340-3120 m a.s.l) steep rock-plucked surfaces. From the foot of this rock face to the valley bottom, a 400 m wide and 200 m long deposit covers the slope. Here, five SE-facing elongated ridges developed along the deposit from 3120 to 2870 m a.s.l. The deposit is composed of subangular to angular metric-sized boulders embedded in a sandy matrix. The geomorphological context and sedimentological features suggest traces of ice flux dynamics, typically observed in debris-covered glaciers.
In the Mangaung catchment, two S-facing cirque-shaped basins were analysed. The eastern one has two well-developed parallel ridges at ca. 3210-3110 m a.s.l with subangular-subrounded metric-size boulders embedded in the sandy matrix that are considered lateral moraines. The centre of the basin has polished surfaces with striations suggesting former temperate subglacial abrasion. At the bottom of the western basin, a 1 km long and 60 m wide block stream developed between 3160 and 2980 m a.s.l. It has elongated ridges and is composed of matrix-free boulders whose central axis preserves alignment patterns downvalley.
The climatic conditions under which these features developed will be revealed in future results from CRE dating, palaeoclimate simulations and palaeoglacier modelling.
How to cite: Fernandes, M., Biskop, S., Vivero, S., Grab, S., and Engelbrecht, F.: New evidence of past glacial and periglacial landforms in the Drakensberg, southern Africa, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3777, https://doi.org/10.5194/egusphere-egu25-3777, 2025.
The glaciology community aims to link climate with moraine positions; however, this is challenging because the glacial dynamics responsible for moraine deposition depend on both precipitation and temperature. These dynamics are further influenced by various physical parameters, such as valley hypsometry (Pratt-Sitaula et al., 2011). Consequently, many studies focus solely on dating morphologies to discuss relative chronologies, rather than attempting to reconstruct past climates from moraine extents. Thus, even though moraines are a key archive of continental paleoclimatology, they have not yet delivered their full potential in reconstructing past climates.
To overcome these issues, we propose a novel methodology for interpreting past climate conditions using sets of moraines from different glaciers that (i) have close or similar ages and (ii) lie close enough to each other to assume they experienced the same paleoclimate. We rely on simulations performed with the numerical glacier model Elmer/Ice, which combines a 3D full Stoke-type glacier flow model with a distributed surface mass balance model, accurately capturing glacier dynamics and geometry sensitivity to valley hypsometry. Within a steady state setup, we simulate the extent of two neighboring paleo glaciers under different precipitation (P) and temperature (T) conditions, finding a P-T solution curve for each that explains the glaciers position/volume constrained by their moraines. The intersection of both curves, therefore, reveals the climatic condition that dominated the valley during the age of the moraines.
We implemented our method in the altiplano valley of Zongo, Bolivia, taking advantage of the long-term glaciological monitoring of the Zongo glacier to calibrate our mass balance model. We studied late-glacial moraines from Telata and Charquini (5390 m asl), two neighboring paleo glaciers with almost the same geomorphological characteristics. We also considered the Zongo glacier itself (6088 m asl), but since it does not have moraines that match the ages of those from Telata and Charquini, we created a similar moraine formation for analysis purposes. Charquini and Telata showed close and almost parallel P-T solution curves, which were crossed by the steeper solution curve of Zongo, thus highlighting the dependence of our method on hypsometry contrasts between glacial valleys.
The fact that these P-T curves have a single intersection suggests that, with a good elevation contrast, our methodology allows us to reconstruct past climatic conditions and decipher the joint contribution of precipitation and temperature from moraine positions only, which has never been achieved in previous studies based on ELA reconstruction or energy balance models (e.g., Autin et al., 2022; Rabatel et al., 2006) where strong assumptions about P or T are needed. We are currently working with two other Altiplano paleoglaciers (Aricoma and Llampu) that have a good hypsometry contrast and will allow us to compare the P-T results with the paleoclimatic conditions presented in the literature (e.g., Martin et al., 2018; Jomelli et al., 2014), enhancing our understanding of the regional signature of global climate changes.
How to cite: Acuña Reyes, N., Martin, L., Gilbert, A., and Jomelli, V.: Reconstructing paleoclimates through 3D numerical modeling of tropical Andes paleoglacial flow., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10384, https://doi.org/10.5194/egusphere-egu25-10384, 2025.
The last glacial termination (LGT; ~19.6-11.7 ka) was a period of rapid climate change. Global temperatures increased by ~6ºC, causing extensive ice mass loss, large shifts in atmospheric and ocean circulation, and approximately 120 m of sea level rise. However, records indicate that warming during the LGT was not uniform, with several abrupt, high-amplitude changes in temperature recorded in North Atlantic proxy records. Because climate models currently struggle to replicate these rapid climate events, it is crucial to produce additional climate proxy data, particularly from the underrepresented terrestrial realm, to better understand these changes and their potential to inform future climate models.
Mountain glaciers respond rapidly to climate forcing, and thus are sensitive indicators of changes in climate. Mapping and dating past glacier fluctuations provides important information about changes in past glacial mass balance, which can be used to understand the timing and magnitude of associated climate change. In Ireland, immediately downwind of the North Atlantic, there is extensive evidence that mountain glaciers occupied mountain ranges across the island as the British-Irish Ice Sheet receded during the LGT. Therefore, investigating past Irish mountain glacier fluctuations provides the opportunity to examine a terrestrial signal of abrupt climate change in the North Atlantic region.
Here we present an overview of the Abrupt Climate Change in Terrestrial Ireland (ACCTIR) project, which aims to use past Irish mountain glaciation to investigate palaeo-climate in the terrestrial North Atlantic during the LGT. ACCTIR pairs geomorphic mapping and cosmogenic surface-exposure dating of mountain glacier moraines with glaciological modelling to establish the timing and magnitude of glacial – and thus climatic – change in terrestrial Ireland during the LGT. We present new glacial-geomorphic mapping of target field areas in southern Ireland, as well as unpublished surface-exposure ages from the Wicklow Mountains. Once the dating is complete, we will combine our results with previously published ages to model potential climate scenarios compatible with past glacial fluctuations. This work will provide a range of quantitative data that will be useful for improving climate and glaciological models and will help us to better understand North Atlantic climate variability.
How to cite: Dulfer, H. E., Jackson, M. S., Kelley, S. E., Bromley, G. R. M., and Eaves, S.: Using past Irish mountain glaciation to improve our understanding of abrupt climate changes in the terrestrial North Atlantic during the last glacial termination, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10213, https://doi.org/10.5194/egusphere-egu25-10213, 2025.
Despite extensive research on Last Glacial Maximum (LGM) glaciers, the complexity of the record means that data are often fragmented and regionally focused, limiting the availability of cohesive global field-based reconstructions and models. Developing methods to work globally is necessary to uncover undocumented glaciations and gain a better understanding of the extent of past glacial systems. In this study we used a 30 arcsecond, degree-day based glacial inception threshold map, estimating the temperature reductions required for glaciation relative to the current climate. By integrating results from eleven PMIP4 (Paleoclimate Modelling Intercomparison Project Phase 4) simulations, we identified areas where temperatures dropped sufficiently during the LGM to support glaciation in each model, and aggregated them into a global map of the number of PMIP4 models predicting conditions for glacial inception. To validate these findings, we used a dataset of 10Be and 26Al radionuclide dates from glacial landforms. Using these dated points as outlet locations, we delineated watershed basins approximating potential glacier extents. The resulting polygons were merged with a vector map of documented glacial extents and then spatially compared to the modelled inception areas. Initial results indicated that only 25.99% of the documented LGM glaciers align with the aggregated inception areas as modelled by the majority of PMIP4 models, while 74.01% remain unreproduced, likely due to paleoclimate modelling resolution and spatial mismatches between inception areas and outlet points. Conversely, 49.19% of the inception areas lacked corresponding documentation, suggesting the potential existence of previously unreported glaciers. When considering regions where at least one PMIP4 model predicts threshold temperatures, 67.01% do not correspond with known paleoglaciers. Areas where all models agree on suitable conditions for glaciation, coincide with only 6.06% of documented glaciers. Future research could refine these methods by incorporating higher-resolution palaeoclimate model outputs and using ice flow modelling to delineate glacier extents more accurately.
How to cite: Van Cappellen, M., Seguinot, J., Legrain, E., and Zekollari, H.: Global Glacial Inception Areas during the Last Glacial Maximum, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6672, https://doi.org/10.5194/egusphere-egu25-6672, 2025.
The Ivrea Morainic Amphitheatre (IMA; western Italian Alps) is a promising site to investigate the potential asynchrony of Late Pleistocene glaciations. This extensive end-moraine complex was built by the cyclic Quaternary expansions of the Dora Baltea glacier in the southern Alpine foreland. However, the available geochronological data6, 7 are too limited to quantitatively attribute each sub-system of moraines to different glacial advances. The present work aims to provide new chronological constraints to the innermost glaciogenic succession of the IMA. To this aim, luminescence dating is applied on proglacial glaciolacustrine and glaciofluvial deposits associated to different stages of ice advance. The obtained chronology (ca. 30 samples) provides new insights into the Late Pleistocene glacial history of one of the largest morainic amphitheatre in the European Alps, contributing to the ongoing discussion on asynchronous paleoglacial dynamics during this period.
References
[1] Doughty et al., 2021, Quaternary Science Reviews 261.
[2] Hughes et al., 2013, Earth-Science Reviews 125.
[3] Gribenski et al., 2021, Geology 49.
[4] Monegato et al., 2017, Scientific Reports 7.
[5] Kamleitner et al., 2023, Geomorphology 423.
[6] Gianotti et al., 2008, Quaternary International 190.
[7] Gianotti et al., 2015, Alpine and Mediterranean Quaternary 36.
How to cite: Serra, E., Gianotti, F., Mueller, D., Monegato, G., and Preusser, F.: Late Pleistocene glacial history of the Ivrea Morainic Amphitheatre, western Italian Alps, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5484, https://doi.org/10.5194/egusphere-egu25-5484, 2025.
Running along the spine of the Italian Peninsula, the Apennine mountains contain numerous traces of Late Pleistocene glaciations. Most glacial sediments and landforms in the Apennines, such as frontal and lateral moraine ridges, have been tentatively ascribed to the Last Glacial Maximum (LGM). Numerical age control to confirm this hypothesis, however, is only available at very few sites, in particular in the Tosco-Emilian Apennines. Improving glacial chronologies in other sectors of the mountain range is necessary to understand how glaciers in the Italian Peninsula responded to variations in the position of the North Atlantic storm track and changes in Mediterranean circulation throughout the Late Pleistocene.
GLAMED is a new project funded by the University of Padova that aims at better constraining the Late Pleistocene glaciation history in different sectors of the Apennines by integrating geomorphological mapping with the analysis of soil profiles and various geochronological techniques. First field campaigns in the northernmost part of the mountain range (Ligurian Apennines - Aveto catchment) have revealed the existence of small, confined mountain glaciers, likely related to the LGM. However, there is also scattered evidence for a much more extensive and older glaciation, possibly during MIS 6, which has not been described in the northern Apennines previously. Samples for surface exposure dating have been collected to test this hypothesis and to compare the results with chronological data from the central and southern part of the mountain range.
How to cite: Rettig, L., Mozzi, P., Monegato, G., Ribolini, A., Spagnolo, M., Rellini, I., and Maerker, M.: GLAMED Project: Unravelling the Late Pleistocene glaciation history of the Apennine mountains (Italian Peninsula), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11805, https://doi.org/10.5194/egusphere-egu25-11805, 2025.
During the Pleistocene epoch the Alpine scenery with its surroundings was repeatedly reshaped by glacial activity. Subglacial erosion led to basin-shaped structures, so-called ‘overdeepenings’ (OD), embedded in bedrock. Their sedimentary fillings are important archives for understanding glacial history and the glacial impact on environmental transformation. Some of these infills are composed of multiple cycles representing separate glaciations.
Numerous well investigated cores in the Northern Alpine Foreland led to the recognition of typical fining-upward OD-fill sequences – characterized by glaciolacustrine deposits overlying glacially originated diamicts at the basal unconformity (e.g. Gegg & Preusser 2023, and references therein). These fining-upward sequences typically start with glacitectonites that regularly transition into coarse-grained, sand-dominated, and finally fine-grained basin fills, and can occur as several unconformably stacked units (Buechi et al. 2024).
In the ICDP-DOVE framework (Anselmetti et al. 2022), two new cored profiles were recovered north of Lake Constance (drill sites Gaisbeuren and Lichtenegg). These consist of OD-fills that are not typical for the Alpine Foreland, because they are almost entirely composed of diamictic deposits. While these deposits show some variations in concentration and size of clasts, well sorted lacustrine sediments are missing. Here we aim to start a discussion about potential reasons for the atypical character of these OD-fills.
Anselmetti, F.S., Bavec, M., Crouzet, C., Fiebig, M., Gabriel, G., Preusser, F., Ravazzi, C., DOVE scientific team, 2022. Drilling Overdeepened Alpine Valleys (ICDP-DOVE): quantifying the age, extent, and environmental impact of Alpine glaciations. Scientific Drilling, 31, 51–70. https://doi.org/10.5194/sd-31-51-2022.
Buechi, M.W., Landgraf, A., Madritsch, H., Mueller, D., Knipping, M., Nyffenegger, F., Preusser, F., Schaller, S., Schnellmann, M., Deplazes, G., 2024. Terminal glacial overdeepenings: Patterns of erosion, infilling and new constraints on the glaciation history of Northern Switzerland. Quaternary Science Reviews, 344, 108970. https://doi.org/10.1016/j.quascirev.2024.108970.
Gegg, L., Preusser, F., 2023. Comparison of overdeepened structures in formerly glaciated areas of the northern Alpine foreland and northern central Europe. E&G Quaternary Science Journal, 72, 23–36. https://doi.org/10.5194/egqsj-72-23-2023.
How to cite: Pomper, J., Zeeden, C., Preusser, F., Wielandt-Schuster, U., and Gegg, L.: Two atypical overdeepening-fills from the Lake Constance area (Southern Germany), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17419, https://doi.org/10.5194/egusphere-egu25-17419, 2025.
The erosive impact of glaciers during the Last Glacial Maximum (LGM) has largely obscured evidence of earlier, less extensive glacial advances within the Alps. While Alpine paleoclimate records show that the Marine Isotope Stage (MIS) 3 was characterized by pronounced changes between stadial and interstadial conditions, similar to the Dansgaard-Oeschger (D-O) cycles observed in ice-cores from Greenland, depositional evidence of glacial extent during this period remains scarce. Here, we present new data from a sedimentary archive in the inner-alpine Bad Aussee Basin in the Austrian Eastern Alps. Located close to the main accumulation areas of the former Traun Glacier, its topographic setting suggests that down-valley glacial damming is a major factor controlling the timing of depositional phases throughout glacial-interglacial cycles. Under present interglacial conditions, fluvial incision takes place.
Our investigations are focused on an 880-m-long Pleistocene sedimentary record, recovered by a drilling intended for salt exploration and later included in the ICDP (International Continental Scientific Drilling Program) project DOVE (Drilling Overdeepened Alpine Valleys). Three distinct depositional phases can be distinguished. The basal Unit A (880–580 m), dominated by glaciolacustrine deposits, can be correlated with the Penultimate Glaciation (MIS 6) based on luminescence dating and consists of locally sourced material from the Northern Calcareous Alps. In contrast, Unit B (580–67 m) records a succession of lacustrine and deltaic sediments largely derived from the Austroalpine crystalline basement to the south of the Enns Valley. Luminescence results indicate that deposition took place mainly during MIS 3. Unit B exhibits several abrupt increases in total organic carbon (TOC), which we interpret as organic productivity events, followed by a gradual decrease. This TOC pattern closely resembles the D-O cycles, allowing a tentative correlation between individual events. Unit C (67–0 m) consists of subglacial till which we attribute to the LGM, although no numerical dating results are available.
Based on the sedimentological, chronological and provenance data, this study presents a reconstruction of the pre-LGM landscape evolution of the Bad Aussee Basin with particular focus on the MIS 3 stadial-interstadial cycles. Placing our results in a broader regional context, we discuss the implications for glacial dynamics and drainage evolution in the Traun and Enns valleys.
How to cite: Schmalfuss, C., Firla, G., Neuhuber, S., Lüthgens, C., Diendorfer, P., Leitner, T., Anselmetti, F., and Fiebig, M.: Reconstructing pre-LGM landscape evolution in the Eastern Alps (Austria): New insights from the Bad Aussee Basin, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11353, https://doi.org/10.5194/egusphere-egu25-11353, 2025.
The Adige glacier during the Last Glacial Maximum (LGM) spread into different branches downstream of Trento. Here, reliefs exceeding 2000 m in elevation are present, which hosted local plateau glaciers, namely: Pasubio, Vigolana, Campoluzzo and Fiorentini. The present Adige valley was filled by one of the major Alpine glaciers with an ice-thickness exceeding 1500 m, as testified by well-expressed lateral moraines. On the southern Vigolana, the Adige lateral moraine cuts those belonging to the local glacier, suggesting an early advance of the plateau glacier before the maximum spreading of the Adige glacier. This branch flowed into the left tributary valleys, which were dammed and acted as local depocenter for glaciofluvial and slope deposition. Another minor branch of the Adige glacier overflowed the Carbonare saddle towards the Astico valley, which in his middle sector was filled by a 600-m-thick tongue, as documented by the lateral moraines of Tonezza. This glacier dammed the Posina valley, which was filled by glaciofluvial deposits related to Pasubio and Campoluzzo glaciers. Field observations and remote sensing analyses allowed for the modeling of the Equilibrium Line Altitudes for both valley and plateau glaciers.
How to cite: Monegato, G., Rettig, L., Rossato, S., Mozzi, P., and Picotti, V. and the CARG Rovereto scientific team: Tracking the LGM glaciers across the Adige and Astico valleys (European Alps, Northern Italy), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12174, https://doi.org/10.5194/egusphere-egu25-12174, 2025.
