No abstract

This paper describes seasonal variations on Strandline Glacier, Terra Nova Bay, northern Victoria Land, Antarctica, obtained from measurements during two field campaigns (2000/01 and 2002/03). By applying different methodologies and techniques, it was possible to calculate summer changes in thickness (mean decrease over the whole glacier surface of 0.04 m w.e.) and in volume (decrease of 352 m 3 at the terminus). This serves to identify and quantify the processes responsible for these variations (e.g. melting, evaporation, wind erosion/deposition and calving) and to understand the energy transfers at the glacier-air interface. One particular feature of the glacier is the presence of an ice cliff at the terminus, which causes ablation owing to dry calving. This process brought about a summer retreat rate of 1 m week -1 in the central part of the front during the study period. Qualitative observations carried out during previous field campaigns and quantitative analysis performed during the last two expeditions have provided an understanding of the mechanism underlying the ablation processes, thus confirming the available literature on this topic.

We have studied the internal climate of the Borna Maggiore di Pugnetto (Western Alps), starting from the survey of geological structure, of geomorphology and of vertical distance between cave floor and topographic surface. Then we studied the variations in temperature in the soil and in the air; the distribution of temperature and humidity in soil and air on four days that representing the four seasons. According the geomorphic data, the Borna is a through cave (hydro-geological tunnel). Three major heat sources regulate the thermal dynamics of the cave. In a branch enters water relatively warm, which is the main responsible for the distribution of temperature in this part of the cave. The entrance (at the opposite side of the cave) puts in communication the cave with the outer atmosphere, causing temperature changes, more and more attenuated inwards. Thermal imbalance between cave's ends probably causes the air circulation, which tends to homogenize the temperature of the air and soil, especially in the innermost part of the cave. The drip water is the third heat source: after the rains, causes sudden changes in temperature since October until June, after the starting of period of water surplus. The thermal dynamic of the cave makes almost constant temperatures, and divides the inner atmosphere in thermic zones, such as cold depressions, areas with constantly mild temperature, and traps to the warm air. This, combined with the constant temperature difference between air, walls and floor of the cave, creates many adjacent microhabitats. This factor, together at the proximity to glaciers in past, explains the great biodiversity of the cave.

Erratic blocks are the main geosites in Turin's suburban area. Today, they are a symbol of the ‘landscape to be saved’ even for those who are barely aware of their geological importance. This is because the blocks are the subject of myths (based on their geomorphological characters), such as: interpretation of weathering as altars or runic writing: attribution of strange shapes, noises, lairs, to petrified supernatural beings: interpretation of isolated blocks as dwellings of protector beings; use of the blocks for boulders: supposed reports of UFOs and ‘disappeared civilizations’. In ancient times, erratic blocks were at the centre of religious practices. However, most myths are in fact recent. The Barbarian invasions and the fight against Paganism destroyed the ancient myths. The creation of new myths proves that erratic blocks are able to attract mankind's attention in every epoch. When the geologist proposes blocks as protected geosites, he must show the connection between geomorphology and myths, maintaining the suggestive impact of the myths. Myths, including recent and altered ones, can work together with scientific explanation to make it easier for the public to understand the true importance of erratic blocks. By exploiting the power and appeal of myth, the community will more easily accept the need to preserve scientifically valuable geosites.

ABSTRACT. Melting is a fundamental process in glacier mass balance as well as in other glacial processes such as ice movement, ice avalanches and snow metamorphism. At Terra Nova Bay, Antarctica, the annual mean temperature is <0˚C but melting is not negligible. Our data show that melting is present up to 1300 m a.s.l. The distribution and relative importance of melting change with elevation and exposure. At low elevation and with a southerly exposure, melting is one of the major summer ablation processes, synergetic with dry calving and katabatic wind. Meltwater seepage reaches the glacier substrate. Discharge appears to be linked to irradiation, offset by a few hours relative to it. The frontal area of the glaciers therefore behaves like an aquifer, and its characteristics depend on the morphology of the front. As elevation increases, melting at first becomes limited to the snowpack, then to low-albedo cases, for example when dust is brought in from the areas surrounding the glacier. In this case, melting limits ablation, providing the snow with increased resistance to wind erosion.