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The Antarctic continent reached its current polar location ~83 Ma and became shrouded by ice sheets ~34 Ma, coincident with dramatic global cooling at the Eocene-Oligocene boundary. However, it is not known whether the first Antarctic glaciers formed immediately prior to this or were present significantly earlier. Here we show that mountain glaciers were likely present in the Transantarctic Mountains during the Late Palaeocene (~60–56 Ma) and middle Eocene (~48–40 Ma). Temperate (warm-based) glaciers were prevalent during the Late Eocene (~40–34 Ma) and, in reduced numbers, during the Oligocene (~34–23 Ma), before larger, likely cold-based, ice masses (including ice sheets) dominated. Some temperate mountain glaciers were present during the Miocene Climatic Optimum (~15 Ma), before a widespread switch to cold-based glaciation. Our findings highlight the longevity of glaciation in Antarctica and suggest that glaciers were present even during the Early-Cenozoic greenhouse world. This study finds that glaciers have existed in the Transantarctic Mountains for the past 60 million years, and that warm-based mountain glaciers were present in Antarctica long before ice sheets came to dominate the continent. [ABSTRACT FROM AUTHOR]

The Atlantic mountains of Spain are suffering a strong landscape change due to a widespread and intensive emigration to urban areas since the 1950s. This process, representative of global developments in an imminent future, is dominated by urban societies and leads to deep landscape changes in which crop fields and grasslands are abandoned and progressively covered by forest and shrubs. These dynamics have caused in turn a decrease in the runoff and a general slowdown of geomorphological processes. The impacts of land cover change have been simultaneous to an irregularity in precipitation and a significant increase of temperatures. With this background, this paper assesses in detail the impact of landscape change occurred over the last decades (twentieth and twenty-first centuries) on the water and sediment yield in the Pisuerga catchment headwaters (Cantabrian Mountains, N Spain). We analyzed the different components of Global Change in a catchment of 233 km2 extent, that has passed from 15 to 2 habitants/km2, from multiple data sources. Evolution of land cover was reconstructed from aerial photographs, remote sensing and other resources. The climatic parameters have been studied through meteorological stations, and the hydrological and sedimentological responses over time are based on available runoff data and sedimentological analysis. Our results show a significant decrease in water and sediment transport mainly driven by vegetation increase occurred in a non-linear way, more intense immediately after abandonment. This fact opens the opportunity to control more accurately water resources in Mediterranean catchments through land use management. [ABSTRACT FROM AUTHOR]

New 10Be dates for glacial landforms in the Fuentes Carrionas area (Cantabrian Mountains, nothern Spain) are presented. Mapped and dated landforms in Fuentes Carrionas made possible a palaeoglacier reconstruction for four glacial stages. Results were compared to other nearby palaeoenvironmental proxies, so a final approximation on the mean annual temperature and annual precipitation that caused the four glacial advance stages is proposed. Glaciers reached their maximum extension at 36 ka, in a cold and dry environment. A second advance stage took place between 18.5 and 19.5 ka, during the Last Glacial Maximum (LGM), when glaciers advanced in a wet environment, with positive rainfall anomalies. A third glacial advance was dated during the Oldest Dryas, in which climate shifted to extremely cold and dry conditions. Finally, a last stage has been identified and proposed to the Younger Dryas, in which precipitation anomalies are negligible. Our results confirm some of the previously made palaeoglacial and palaeoenvironmental inferences for the Iberian Peninsula, as well as provide valuable and accurate anomalies, which are useful for climate modelling. [ABSTRACT FROM AUTHOR]

A 1:12,000 geomorphological map of Fuentes Carrionas (Northern Spain) is presented. Geomorphological landscapes maps are also shown to support map interpretation and show the area's geomorphological diversity. The maps were developed using the IGUL (Institut de Géographie, Université de Lausanne) geomorphological mapping legend. This has been adapted to GIS scheme in order to use the map as a basis for further work. The IGUL legend has been demonstrated to be highly effective for mountain environments where the main morphogenetical agents are dynamic and climatic processes. [ABSTRACT FROM AUTHOR]

Mountain areas are particularly vulnerable to climate change as the local variations in elevation and aspect amplify general trends in temperature and precipitation alteration. Many of the mountain areas are also under increasing direct human pressure, which is related to food production, settlement, mining, and other direct earth-moving activities. As a response to such external drives, the increase in frequency and magnitude of geomorphic processes has been observed in many places around the world. Our project focuses on catastrophic geomorphic processes (mainly debris flows, landslides, accelerated soil erosion) as an example of a land-surface response to environmental (including climatic and anthropogenic) change. The research is conducted in two locations in the Andes (Eje Cafetero, Colombia and Quispicanchi Province, Peru), representing different climatic conditions and various degrees of direct human impact. The Eje Cafetero region is located on the slopes of the central and western Cordillera of the Colombian Andes. The average slope is approximately 45 degrees. The seasonal rain passes over the region twice a year. Pressure for urban development, mass-tourism and gold mining constitutes the biggest socio-economic threats that can impact land use in the area. Landslides are the most significant natural hazard, which very often disturbs transportation system, destroying crop areas, and threatening small towns. Quispicanchi Province is located in the southern highlands of Peru. The main focus is on the Willkanuta (Cordillera de Vilcanota) - mountain range which is much less populated than Eje Cafetero, thereby allowing us to study surface dynamics not related to direct human impact. Meanwhile, landslides and debris flows (partly preconditioned by glacier recession) still constitute a serious threat to human infrastructure (roads, villages, etc.), and life. This study aims to develop an operational framework for geohazard assessment and monitoring in mountain areas. We use a multidisciplinary approach that links remote sensing mapping, geomorphological fieldworks, unmanned aerial vehicle surveys (UAV) and GIS analysis. We mapped geomorphic traces of mass movements (debris-flow channels, erosional rills, rockfall deposits and landslides) that were visible in different years based on a time-series of high-resolution (<1.0 m) satellite imagery. This spatial database was subsequently enriched with information about geology (from geological maps) and topography (slope, aspect, curvatures, slope length, etc.) based on the photogrammetrically-derived Digital Elevation Models (DEMs). The database enabled us to investigate the distribution of mass movement processes and related landforms over the modern landscape and asses their dynamics over the last 15 years. The results will be used to assess the impact of observed geohazards on the provision of ecosystem services across studied mountain landscapes. The research was founded by the Polish National Science Centre, Poland (Project number 2015/19/D/ST10/00251) [ABSTRACT FROM AUTHOR]

We map glacial cirques, and analyse spatial variability in their altitude and aspect to derive a long-term, time-integrated, perspective on climate patterns during former periods of mountain glaciation (likely spanning multiple Quaternary glaciations) in Britain and Ireland. The data reveal that, although air temperatures were important, exposure to moisture-bearing air masses was the key factor in regulating sites of former mountain glacier formation, and indicate that during such periods, moisture supply was largely controlled by North Atlantic westerlies, with notable inland precipitation gradients (precipitation decreasing inland), similar to present day. In places, trends in cirque altitude may also reflect regional differences in the extent of cirque deepening, controlled by the dimensions and dynamics of the glaciers that came to occupy them. Specifically, comparatively deep cirques in coastal locations may reflect the former presence of dynamic (fed by moisture from the North Atlantic), but comparatively small, glaciers (largely confined to their cirques). By contrast, decreasing cirque depth further inland, may reflect the former presence of larger and/or less dynamic ice masses, occupying comparatively continental climatic conditions. [ABSTRACT FROM AUTHOR]