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Here we present an integrated earth surface process and paleoenvironmental study from the Tingri graben and the archaeological site of Su-re, located on the southern rim of the Tibetan plateau, spanning the past ca. 30 ka. The study area is characterized by cold climate earth surface processes and aridity due to its altitude and location in the rain shadow of the Mount Everest–Cho Oyu massif and is thus sensitive to climatic and anthropogenic perturbations. During the global last glacial maximum (gLGM) glaciers from the main Himalaya range advanced into the Tingri graben and deposited massive hummocky moraines, while the zone of discontinuous permafrost was depressed by ~450 m relative to today, greatly intensifying permafrost and periglacial hillslope processes and leading to fluvial aggradation of the valley floors of ≥12 m. We observe formation of a thick (≥50 cm) pedo-complex starting at ca. 6.7 ka before present (BP) and erosional truncation at ca. 3.9 ka BP. Widespread landscape instability and erosion characterize the region subsequent to 3.9 ka and intensifies in the 15th century AD. Several lines of (geo)archaeological evidence, including the presence of pottery sherds, sling-shot projectiles and hammer stones within the sedimentary record, indicate human presence at Su-re since ca. 3.9 ka BP. Our data suggest that in the Su-re-Tingri area climatic conditions were warm and moist enough to allow vegetation expansion and soil formation only from ca. 6.7-3.9 ka, followed by weakening of the Indian summer monsoon (ISM) strength between ca. 3.9 and 4.2 ka, which is a prominent climatic event in the wider Asian monsoon region, and reflected in the investigation area by the 3.9 ka erosional boundary. Merging our Holocene landscape reconstruction with the geoarchaeological evidence, we speculate that the combined effect of Little Ice Age (LIA) cooling and an anthropogenic overuse of the landscape led to climatically induced landscape degradation and ultimately to an anthropogenically triggered ecological collapse in the 15th century. Such a scenario is in-line with regional historical data on declining monastery construction and migration of the ethnic group of the Sherpas. From an earth surface dynamics perspective, we find that short-term transient landscape processes on the southern rim of the Tibetan plateau are strongly linked to millennial scale changes in the ISM intensity and duration. We identify three types of unidirectional non-linear ISM-landscape interactions. Given that the Tibetan plateau is the largest high-altitude landmass on our planet and our limited understanding of several of the key earth surface processes on the plateau, we pinpoint the need for more long-term (Quaternary scale) empirical data particularly on permafrost and periglacial processes and human-environment interactions.

The thawing of alpine permafrost in a warmer climate may alter the runoff regime of high alpine catchments. We present a case study where detailed geophysical and geological field investigations were performed in a 5 km2 large catchment in Western Austria to assess its main hydrogeological settings. Ground-penetrating radar data, seismic refraction measurements and ground-surface-temperature data were employed to map the spatial permafrost distribution and depth of the permafrost table and the bedrock interface. The results for different types of unconsolidated sediments were then translated into five sets of flow path concepts in the presence and absence of permafrost. These concepts were then used to set up a rainfall-runoff model and simulate the runoff response of the catchment for scenarios with and without permafrost. The simulations indicate that the complete thawing of permafrost will increase the catchment storage capacity which will reduce the flood peaks by up to 20% and increase runoff during recession by about 15%. The reduction of extreme events is important since it may also affect flood events in downstream catchments. The study highlights the importance of interdisciplinary work between hydrology, geophysics and geology which can greatly help to improve the understanding of subsurface processes.

Alpine permafrost is prone to decrease in a warmer climate as a consequence of climate change which in turn may affect the runoff regime of high alpine catchments. In the presented case study detailed geophysical field investigations were performed in a 5 km2 large catchment in Western Austria to gain information about subsurface properties and permafrost occurrence. Ground penetrating radar, seismic refraction and ground-surface-temperature measurements were applied to map the spatial permafrost distribution, depths to the permafrost table and bedrock interface. This information was used to infer subsurface flow paths concepts for different geologic formations in the presence and absence of permafrost. The concepts were then used to set up a rainfall-runoff model and simulate the runoff response of the catchment for scenarios with and without permafrost. The results of the study show that geophysical information helps to improve the understanding of subsurface processes and to reduce the parameter identifiability problem. Subsurface model parameters are well constrained by the available field information and require little calibration. Furthermore, the simulations indicate that the melting of permafrost increases the available catchment storage which causes a reduction of flood peaks and an increase of runoff during recession. A reduction of extreme events is important since it may also affect flood events in downstream catchments.

Algebra became part of mathematics education in the Netherlands in course of the seventeenth century. At first in the form of cossic algebra, but by the end of the century, the influence of the notation of Descartes was noticeable. In the eighteenth century, algebra was part of the basic curriculum of the Foundation of Renswoude. In the second half of the nineteenth century, algebra was seen as useful for a technical career. The number of topics in school algebra grew, but eventually algebra became mainly a subject in which complicated calculations were performed, which did not seem to serve a purpose outside the subject. At the end of the twentieth century, school algebra in lower secondary became a fairly informal way of solving ‘practical’ problems.

To engage in challenging tasks, students need to feel some autonomy and competence. Providing structure within the task can help to meet these needs. This study investigates the influence of structure within a modelling task on mathematical creativity among 79 eleventh grade groups of students. Two versions of the task were developed and the groups were randomly assigned within their classroom to one of these. The analysis explored: (i) the level of mathematical creativity in groups solutions and (ii) if they were dependent on the amount of structure. The results were not statistically significant and, therefore, the question remains open. Additional results and implication of this study to mathematics education are further discussed.

Ortles mountain (3905 m a.s.l.), South Tyrol, Italy, is the highest mountain of the Eastern European Alps, and its upper glacier, Alto dell'Ortles, presents a unique opportunity to obtain the first paleoenvironmental record from an ice core in this area. To study the suitability of this glacier as a drilling site, in 2009 we performed the first preliminary study of its glaciological characteristics at similar to 3830 m a.s.l. The maximum thickness is similar to 75 m, and lamination of the exposed ice layers is excellent down to bedrock. Firn and ice lenses were observed in a 10 m shallow core, and the firn/ice transition was below similar to 24 m. The seasonal chemical signal is clearly preserved only within the uppermost 2008 and 2009 snow/firn. A simple mass-balance model, the incipient 'smoothing' of the chemical record, and the observed ice lenses provide evidence that melting, infiltration and refreezing cycles occurred within the urn layers formed before 2008. Nevertheless, the mass balance of the upper part of Alto dell'Ortles was positive (similar to 800 mm a(-1)) during the last few years. We suggest that an environmental history is likely to be well preserved only within the ice layers formed before similar to 1980, when summer air temperature was similar to 2 degrees C colder than today in this area. Clearly the continued warming trend predicted to occur over the next few decades, and the consequent increase in frequency and/or intensity of infiltration processes, will endanger the preservation of the glacial archive conserved in the deep ice layers of Ortles mountain.

International audience; As sediment conveyors, rockglaciers - and more generally the creep of perennially frozen ground may be the source of slope instability processes (e.g. rock falls, debris flows) on steep valley sides in a mountain environment. Any change in the rate of permafrost creep is susceptible to affect both the frequency and magnitude of related slope instabilities. There is currently an increasing interest in the densely inhabitated European Alps to document the behaviour of the high-altitude permafrost environment. Studies on rock glacier dynamics have shown that three superimposed types of temporal variability in surface motion can be envisaged at a secular scale: a seasonal rhythm, changes in annual mean velocities, a decadal to pluri-decadal trend. The present contribution compares and analyses the variations in annual velocities that have been observed at the surface of rock glaciers in the European Alps since 2002/03. It represents a pioneer attempt to synthesize the annual variations of rockglaciers activity at this scale. Short-term changes in surface motion of rockglaciers have been monitored in the European Alps since a few years by several research groups, mostly by means of real time kinematics GPS or geodetic survey using a total station. Annual series have been acquired between 2002/03 and 2006/07 on more than 13 rockglaciers located in different parts of the alpine arc. The provided dataset is analysed paying regard especially to two extreme warm climatic events that affected the European alpine region during the 2003-2007 period: the heat wave of summer 2003 and the 2006-07 warm swell, namely a 15-month period of quasi continuous large positive temperature anomaly between April 2006 and June 2007. Despite different size, morphology, ice content, complexity of flow field, mean annual velocity, seasonal rhythm, etc., the compared rockglaciers have surprisingly shown so far a rather homogeneous and synchronous behaviour since 2003: most of them reached a maximal rate of activity in 2003/04 before that their horizontal velocity dropped drastically in 2004/05 and 2005/06. First results in 2006/07 indicate, at least in the western Swiss Alps, a stabilisation or even a slight increase of velocities. The relative range of variation has reached 20 to more than 50 % in one or two years. The absolute range of variation is much larger for rapidly moving rock glacier. Interannual changes appear to be well related to mean annual ground surface temperature shifts with a delay of approximately 6-12 months reflecting their propagation deeper into permafrost.

Recent interannual variation of rockglaciers surface motion is compared for 16 landforms monitored since a few years in various parts of the European Alps. Large fluctuations have been observed particularly since 2002. The investigated rockglaciers have shown mostly similar behavior whatever their location in the Alpine arc, their size or their velocity. The observed interannual variations appear to be primarily related to external climatic factors rather than to internal characteristics. They are mostly well correlated to mean annual ground surface temperature shifts with a delay of approximately 6-12 months reflecting their propagation deeper into permafrost. Other seasonal factors may play a significant role: a lower intensity of winter ground freezing and/or a larger winter snow accumulation appear to facilitate a higher rate of rockglaciers surface motion., Les variations récentes des déplacements de surface de 16 glaciers rocheux suivis depuis quelques années sont comparés pour 16 appareils. De larges fluctuation sont observées depuis 2002 en particulier. Les glaciers étudiés montrent des comportement similaires à l'échelle de l'ensemble de l'arc alpin. Les variations interannuelles semblent être reliées aux conditions climatiques et non à la structure interne. Elles sont bien corrélées aux température moyenne annuelles de surface avec un temps de réponse de l'ordre de 6-12 mois lié la diffusion d'énergie dans le permafrost. D'autres facteurs saisonniers jouent un rôle significatif: une plus faible accumulation hivernale de neige favorise un déplacement de surface plus élevé.