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The timing and magnitude of Holocene glacial oscillations in most currently ice‐free areas of Antarctica remain unknown. This work focuses on the recent deglaciation in the northern sector of the Fildes Peninsula, King George Island, northern Antarctic Peninsula. The ice cap covering ca. 90% of the island has receded since the Last Glacial Maximum and exposed ca. 29 km2 of ice‐free land. We reconstruct its glacial history based on a dataset of 12 36Cl exposure ages obtained through cosmic‐ray exposure (CRE) dating of moraine boulders, polished surfaces and erratic boulders surrounding the peninsula's northern plateau. Results reveal that the deglaciation of the northern Fildes Peninsula took place during the Holocene Thermal Maximum at 7–6 ka, when warm conditions promoted a massive glacial retreat. The present arrangement of ice‐free areas was in place by 6 ka. Small cirque moraines suggest the subsequent occurrence of favourable climate conditions for glacial expansion fed by intense snow deflation at 4.6 and 1 ka at the foot of the northern plateau. The deglaciation pattern of the Fildes Peninsula resulted from the combined shrinkage of different ice masses, rather than of the long‐term retreat of the King George Ice Cap. No evidence of glacier expansion during more recent cold periods (i.e. the Little Ice Age) was found. These results fit well with regional deglacial histories inferred from lacustrine sediments and raised beaches and complement the existing chronological framework to help better understand the peninsula's Holocene geoecological dynamics. [ABSTRACT FROM AUTHOR]

Although the spatiotemporal oscillations of the Greenland Ice Sheet (GrIS) during the last millennia have played a prominent role in global environmental changes, its glacial response to the natural variability still needs to be better constrained. Here, we focused on the reconstruction of the glacial behavior and deglaciation process along the Tyroler Valley (74° N, 22° E), within the Northeast Greenland National Park. This NW‐SE valley connects with the GrIS via the Pasterze Glacier and divides two ice caps (A.P. Olsen Land and Payer Land), this last one feeding two piedmont glaciers (Copeland and Kløft glaciers). For this study, we combined the interpretation of the spatial pattern of geomorphological features and the chronological framework defined by a new dataset of 15 10Be cosmic‐ray exposure (CRE) ages from glacially polished bedrock surfaces and moraine boulders together with one optically stimulated luminescence (OSL) age of a glaciolacustrine deposit. CRE ages indicate that the deglaciation of the lowest parts of the valley and the exposure of the highest slopes took place during the Early Holocene, at ca. 10–8.5 ka (ka = thousand year [BP]). Furthermore, this ice thinning also favored the disconnection of the valley tributary glaciers. Samples from the moraines of the two tributary glaciers indicate that the deglaciation was not continuous, but it was interrupted by at least three phases of glacial advance during the Neoglacial cooling (before ca. 5.9 ka), and the Little Ice Age (LIA, 0.6, and 0.3 ka). The larger piedmont glacier (Copeland Glacier) occupied the valley floor during these major advances, damming the river and allowing the formation of a proglacial glacial lake upvalley, as confirmed by the OSL date of lacustrine sediments that yielded an age of 0.53 ± 0.06 ka. In short, our study provides new evidence of the relative stability of GrIS and the regional ice caps in the area, in which glacial fronts have been rather stable since their advances during the Neoglacial and the LIA. [ABSTRACT FROM AUTHOR]

Reconstructing mountainous landscape evolution throughout the Quaternary is challenging because of the poor long-term preservation of geomorphic records in a context of rapid surface dynamics and topographic rejuvenation. The Quaternary geomorphic evolution of the western European Alps has been strongly controlled by climatic oscillations between glacial and interglacial periods. Significant erosion and sediment remobilization during these glacial/interglacial cycles have left very few sedimentary archives to quantify the surface dynamics and paleo-environmental conditions within the mountain belt over the last hundreds of thousands of years. Alpine valleys within the periglacial zone are potential candidates to target long-term geological archives, since they may contain alluvial deposits that have been preserved from subsequent glaciations. In the Drac valley (French western Alps), three generations of paleo-valleys are preserved, each of which was filled with alluvial and lacustrine sediments in response to glacial damming downstream. The valleys were incised during subsequent times of glacial retreat, leading to the formation of epigenetic valleys. Detailed 3D mapping of the paleo-valleys was carried out using photogrammetric models to constrain their geometry. Mapping was combined with luminescence dating of alluvial deposits to reconstruct the temporal evolution of the Drac valley. This chronological framework, together with additional data from the literature, allowed us to quantitatively constrain the complex alluvial dynamics along the Drac river during the last ca. 230 ka. Poly-phased alluvial deposition occurred in the most recent paleo-valley between ca. 90 and 20 ka (i.e., from late MIS 5 to MIS 2) in a context of global climate cooling and major Alpine glaciation. Sediment infilling of the intermediate paleo-valley is dated at around 130 ka; i.e., during the late-glacial phase of the penultimate glaciation, at the abrupt warming transition between MIS 6 and MIS 5. Finally, the oldest paleo-valley was filled around 230 ka (during a sub-stage of MIS 7) probably in a cooling and glacial context. The overall alluviation pattern and chronology of the study area highlight the asynchronous and partially contrasting glacial dynamics between the different glacier systems (i.e., Drac, Bonne and Romanche/Isère glaciers) within the Ecrins-Pelvoux massif of the French western Alps. • Record of Pleistocene epigenic paleo-valley evolution in the French western Alps. • Alluvial sediment aggradation recorded during early, pleni & late-glacial periods. • Diachronous response of local Alpine glaciers to Pleistocene climate forcing. • Long-term estimate of fluvial incision rate (0.6–0.8 mm/yr) over the last 250 ka. [ABSTRACT FROM AUTHOR]

The Upper Garonne Basin included the largest glacial system in the Pyrenees during the last glacial cycle. Within the long‐term glacial retreat during Termination‐1 (T‐1), glacier fluctuations left geomorphic evidence in the area. However, the chronology of T‐1 glacial oscillations on the northern slopes of the Central Pyrenees is still poorly constrained. Here, we introduce new geomorphological observations and a 12‐sample dataset of 10Be cosmic‐ray exposure ages from the Ruda Valley. This U‐shaped valley, surrounded by peaks exceeding 2800 m a.s.l., includes a sequence of moraines and polished surfaces that enabled a reconstruction of the chronology of the last deglaciation. Following the maximum ice extent, warmer conditions prevailing at ~15–14 ka, during the Bølling–Allerød (B–A) Interstadial, favoured glacial retreat in the Ruda Valley. Within the B–A, glaciers experienced two phases of advance/stillstand with moraine formation at 13.5 and 13.0 ka. During the early Younger Dryas (YD), glacial retreat exposed the highest surfaces of the Saboredo Cirque (~2300–2350 m) at 12.7 ka. Small glaciers persisted only inside the highest cirques (~2470 m), such as in Sendrosa Cirque, with moraines stabilising at 12.6 ka. The results of this work present the most complete chronology for Pyrenean glacial oscillations from the B–A to the YD. [ABSTRACT FROM AUTHOR]

The Upper Garonne Basin included the longest glacier in the Pyrenees during the Late Pleistocene. During major glacial advances, the Garonne palaeoglacier flowed northwards along ~ 80 km from peaks of the axial Pyrenees exceeding 2800–3000 m until the foreland of this mountain range at the Loures–Barousse–Barbazan basin (LBBb), at 420–440 m. Here, the palaeoglacier formed a terminal moraine complex that is examined in this work. Based on geomorphological observations and a 12-sample data set of 10Be Cosmic-Ray Exposure (CRE) ages, the timing of the maximum glacial extent was constrained as well as the onset of the deglaciation from the end of the Last Glacial Cycle (LGC). Chronological data shows evidence that the external moraines in this basin were abandoned by the ice at the end of the Penultimate Glacial Cycle (PGC) and the onset of the Eemian Interglacial, at ~ 129 ka. No evidence of subsequent glacial advances or standstills occurred during the LGC in this basin were found, as the few existing datable boulders provided in the internal moraine showed inconsistent ages, thus probably being affected by post-glacial processes. The terminal basin was already deglaciated during the global Last Glacial Maximum at 24–21 ka, as revealed by exposure ages of polished surfaces at the confluence of the Garonne-La Pique valleys, 13 km south of the entrance of the LBBb. This study introduces the first CRE ages in the Pyrenees for the glacial advance occurred during the PGC and provides also new evidence that glaciers had already significantly shrunk during the LGM. [ABSTRACT FROM AUTHOR]

We report the first glacial chronology of Mt. Karanfil (3059 m above sea level; a.s.l.), a small mountain in the south-central Taurus Range in Turkey. Well-preserved terminal and lateral moraines are clustered in four groups; M1, M2, M3, and M4, between ∼2000 and ∼2400 m a.s.l., composed of limestone blocks. Each moraine group originated from one to three cirque areas (C1, C2, C3, and C4 cirques) on the mountain's northern face between 2400 and 2600 m a.s.l. The best estimated mean ages of moraines M1 (17.3 ± 2.4 ka), M2 (18.6 ± 1.6 ka), and M3 (20.0 ± 2.6 ka) indicate that glaciers reached their maximum extents on the global Last Glacial Maximum (LGM), and they were persistent till the Late Glacial. The last moraine group (M4), more oriented towards the north, is dated to 14.6 ± 2.4 ka, implying that the M4 glacier lasted a few thousand years more. Also, a relict rock glacier in the C1 cirque floor was dated to 9.9 ± 0.9 ka and testifies to the development of permafrost conditions at the onset of Holocene. The timing of glaciation on Mt. Karanfil is close to the global LGM, as similar terrestrial cosmogenic nuclide chronologies were obtained from other mountains in the eastern Mediterranean. We also used the Parallel Ice Sheet Model (PISM) to reconstruct the glaciers and climate during the LGM on Mt. Karanfil. Twenty-one palaeoclimate simulations were run as a function of present temperature and precipitation to reach the steady-state glacier extents, and the modelled glacial areas were compared with the field-observed ice extents. The best-fit scenarios indicate that the LGM climate on Mt. Karanfil was 8.3 ± 0.5 °C colder than today if the precipitation levels were the same as today. More humid (20% wetter) or arid (20% drier) conditions than today bring the palaeotemperature estimates to 6.9 ± 0.4 °C or 10.4 ± 0.6 °C lower than the present, respectively. • First glacial chronology using twenty-one cosmogenic 36Cl samples on Mt. Karanfil. • Glaciers reached their maximum extents at the end of LGM. • Parallel Ice Sheet Model (PISM) was used to reconstruct palaeoglaciers. • Modelled and observed ice extents were matched to infer palaeoclimate. • LGM climate would be 8.3 ± 0.5 °C colder than today if the precipitation levels were same as today. [ABSTRACT FROM AUTHOR]

During the Late Pleistocene, the main mountain ranges of the Iberian Peninsula were covered by small icefields and cirque and alpine glaciers. The deglaciation triggered paraglacial processes that generated landforms, mostly within the ice-free glacial cirques. In this research we analyse the deglaciation process in the Muxivén Cirque (42°15′N – 6°16′W), in the upper Sil River Basin, which includes some of the largest relict rock glaciers of the Cantabrian Mountains. We addressed this objective by means of accurate geomorphological reconstructions, sedimentological analysis, Schmidt-hammer surface weathering measurements and a dataset of 10 10Be Cosmic-Ray Exposure ages. Results reveal that after ~16 ka, glaciers retreated to the bottom of the cirques at the headwaters of the valley, leaving the walls free of ice and triggering rock avalanches onto the remnants of these glaciers. This paraglacial process supplied debris to a small glacier within Muxivén Cirque, which transformed in two rock glaciers. These debris isolated the ice inside the rock glaciers only for a very short period of time and ended up melting completely before the Younger Dryas. The lower sector of the largest one stabilized at 14.5 ± 1.5 ka, while the upper sector remained active until 13.5 ± 0.8 ka. Previous to the stabilization of the lower sector of the northern rock glacier, at its margin a high-energy debris avalanche occurred at ~14.0 ± 0.9 ka. These data agree with previous research, corroborating the paraglacial origin of most Iberian rock glaciers during the Bølling-Allerød interstadial. [Display omitted] • Glacier retreat triggered rock avalanches that favoured rock glacier formation. • Rock glacier activity lasted for a short time, collapsing before the Younger Dryas. • Rock glaciers stabilized at 14.5 ± 1.5 ka and 13.5 ± 0.8 ka (lower and upper sectors). • A high-energy debris avalanche occurred at ~14.0 ± 0.9 ka at the rock glacier margin. • A good example of the paraglacial origin of many Iberian rock glaciers [ABSTRACT FROM AUTHOR]