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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]

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]

Through a detailed geomorphological study, including thourough mapping of the geomorphic features as well as 10Be Cosmic-Ray Exposure (CRE) dating, the geomorphological evolution of the Mulhacén cirque since the maximum ice extent of the last glacial cycle until nowadays was determined. This glacial cirque is shaped on the northern face of the Mulhacén peak (3479 m a.s.l. 37°03′12″N/3°18′41″W), Sierra Nevada, southern Spain. It includes several depositional and erosional glacial landforms that allowed reconstructing its environmental evolution since the last glacial cycle. Furthermore, the sequence of glacial oscillations from this site was compared to that of other cirques of the massif, evidencing that: (i) new glaciers formed in these cirques during the Younger Dryas (YD), and (ii) disappeared at 11.7 ± 1.0 ka. Depending on the altitude, orientation and height of the cirque walls, the final deglaciation of the cirques generated a diversity of landscapes, including a wide range of glacial and periglacial landforms, such as polished surfaces, sequences of moraines, proto-rock glaciers or large rock glacier systems. No glaciers existed in the Sierra Nevada during the Middle Holocene. Only the cirques whose summits exceed 3300 m, are north-exposed and whose walls exceed 300 m high (i.e. Mulhacén and Veleta) hosted glaciers during Neoglacial phases, including the Little Ice Age (LIA) (approx. 1300–1850 CE). During these periods, climate oscillations favoured the formation of small glaciers in these cirques, which generated large moraine systems with either one polygenic ridge or a sequence of spaced frontal arcs. The existence of glaciers impeded the formation of permafrost-related landforms, such as rock glaciers and protalus lobes until the end of the LIA, when they started to form. These results are compared with the deglacial evolution in 55 cirques from Iberian mountains as well as from glacial cirques from other mid-latitude mountains and subpolar regions. The chronology of their deglaciation as well as the landforms generated during glacial retreat followed similar patterns, with no significant differences at regional scale. For each mountain range, the geomorphological diversity existing in each cirque depends on the local topographic characteristics although they formed during the same climatic phases. • We examine the climatic sensitivity of geomorphic processes in glacial cirques. • We focus on the variety of landforms in glacial cirques of Sierra Nevada, Spain. • In this massif glacial cirques were deglaciated around 14 ka. • Glaciers formed again during the Younger Dryas and disappeared around 11.7 ka. • Most cirques of the North Hemisphere followed the same chronological sequence. [ABSTRACT FROM AUTHOR]