ACCELERATING CLIMATE CHANGE IMPACTS ON ALPINE GLACIER FOREFIELD ECOSYSTEMS IN THE EUROPEAN ALPS

In the European Alps the increase in air temperature was more than twice the increase in global mean temperature over the last 50 years. The abiotic ( glacial) and the biotic components ( plants and vegetation) of the mountain environment are showing ample evidence of climate change impacts. In the Alps most small glaciers (80% of total glacial coverage and an important contribution to water resources) could disappear in the next decades. Recently climate change was demonstrated to affect higher levels of ecological systems, with vegetation exhibiting surface area changes, indicating that alpine and nival vegetation may be able to respond in a fast and flexible way in response to 1-2 degrees C warming. We analyzed the glacier evolution ( terminus fluctuations, mass balances, surface area variations), local climate, and vegetation succession on the forefield of Sforzellina Glacier ( Upper Valtellina, central Italian Alps) over the past three decades. We aimed to quantify the impacts of climate change on coupled biotic and abiotic components of high alpine ecosystems, to verify if an acceleration was occurring on them during the last decade (i.e., 1996-2006) and to assess whether new specific strategies were adopted for plant colonization and development. All the glaciological data indicate that a glacial retreat and shrinkage occurred and was much stronger after 2002 than during the last 35 years. Vegetation started to colonize surfaces deglaciated for only one year, with a rate at least four times greater than that reported in the literature for the establishment of scattered individuals and about two times greater for the well-established discontinuous early-successional community. The colonization strategy changed: the first colonizers are early-successional, scree slopes, and perennial clonal species with high phenotypic plasticity rather than pioneer and snowbed species. This impressive acceleration coincided with only slight local summer warming ( approximately +0.5 degrees C) and a poorly documented local decrease in the snow cover depth and duration. Are we facing accelerated ecological responses to climatic changes and/or did we go beyond a threshold over which major ecosystem changes may occur in response to even minor climatic variations?

Le operazioni cross-border Italia-Cina. Il caso Elica-Zhejiang Putian

L’elaborato analizza le operazioni di Mergers and Acquisitions (M&A), a seguito dell'intenso sviluppo registrato negli ultimi anni su scala mondiale del fenomeno. In una prima parte vengono definite le operazioni e le tipologie possibili, per poi passare alle motivazioni e le metodologie di creazione di valore nelle cross-border in particolare. Nella seconda parte viene analizzato l'andamento del mercato delle M&A, da cui scaturisce l'importanza dei paesi emergenti, compresa la Cina. Vengono in seguito analizzate le operazioni di M&A tra Italia e Cina, cercando di far emergere considerazioni riguardo a: settori, quota di partecipazione e controvalore. L'elaborato si conclude con lo studio di un caso pratico di acquisizione italiana in Cina dell'azienda Elica che opera nel settore delle cappe aspiranti e produzione di motori per elettrodomestici, esaminandone gli aspetti finanziari tramite la metodologia dei multipli di mercato

Preliminary results from antarctic albedo from remote sensing observations

The aim of the study is to analyse the surface albedo of the Ant-arctica and investigate eventual signals of variations in space and time between summer 2000/2001 and 2011/2012 by means of the GLASS albedo product. We followed a step-by-step procedure from micro- to macro-scale. At first, we analysed 95 glaciers around the continent, and we found limited temporal variability. Then, looking at spatial varia-tions, we divided Antarctica based on oceanic basins and by continen-tality. We found spatial signals, since mean albedo values range between 0.79 (Pacific and Atlantic basins) and 0.82 (Indian basin) and between 0.76 (along the shore) and 0.81 (inner continent). An increasing vari-ability was found from the inner continent to the shore, and heteroge-neous patterns among the basins, most likely due to meteorological and environmental conditions (mainly: temperature, precipitation, katabatic winds). Finally, the general patterns observed (considering the specific gla-ciers, the three basins and the three continentality sectors) were verified by the analysis of the whole continent and we did not find a significant change of summer averages over time, as they range between 0.79 and 0.80

Dry calving processes at the ice cliff of Strandline Glacier northern Victoria Land, Antarctica

AbstractThis 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 mw.e.) and in volume (decrease of 352 μ3 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 mweek–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

Distribution of the surface energy budget: Preliminary analysis on the incoming solar radiation. the case study of the Forni Glacier (Italy)

This study represents a contribution to distribution of the surface energy budget of the Forni Glacier (Ortles-Cevedale Group, Upper Valtellina, Italy). The analyses are based on data acquired at S. Caterina Valfurva (a village in the glacier valley at 1768 m ellipsoidal elevation WGS84) by an Automatic Weather Station (AWS) installed and managed by the Lombardy Agency for the Environment ("ARPA Lombardia"). We focus on the two most important meteorological parameters affecting surface energy budget: air temperature (T) and incoming shortwave radiation (SWin). Data collected from the ARPA AWS are used to evaluate these parameters at the glacier surface during the meteorological summer 2009 (from 1st June to 31st August 2009) and then the computations are validated through comparison with data recorded by an AWS installed at the surface of Forni Glacier tongue ("AWS1 Forni", 2669 m ellipsoidal elevation WGS84). The analysis of the distributed air temperature data enabled identification of the lowest value (-11.9 degrees C), found at the Mount S. Matteo peak (3669 m) on 22nd June at 8: 00 pm, and the highest value (+16.1 degrees C), recorded at the glacier terminus (2497 m) on 23 rd July at 2: 00 pm. The seasonal temperature amplitude (Tmax-Tmin) was 28 degrees C. The hottest week was 20th-26th July 2009 and the coldest was 1st-7th June 2009. Regarding daily SWin distribution, the maximum value (406.9 Wm(-2)) was recorded on 13th June and the minimum (28.5 Wm(-2)) on 6th June. From the analysis of hourly SWin values we could distinguish between days with clear sky conditions and days with intense cloud cover. Weekly mean SWin data showed the greatest value (327.1 Wm(-2)) from 20th-26th July 2009 and the lowest (207.8 Wm(-2)) from 22nd-28th June 2009. Furthermore, in analysing SWin it is critical to take into account the problem of shading. Using the Hillshade tool of ArcGIS, which takes into account only the slope and the aspect of each grid cell neglecting the surrounding topography effect, we compiled 66 shadow maps. Finally this study represents a first approach in modelling the distributed incoming solar radiation. In fact the considered driving factors are the elevation, the slope and the aspect of each grid cell. The next step will consist in taking into account the surrounding topography and the actual atmosphere conditions as well

Recent (1975-2003) changes in the Miage debris covere glacier tongue (Mont Blanc, Italy) from analysis of aerial photos and maps

The present study aims at identifying any changes in volume and thickness of the Miage Glacier tongue (Mont Blanc Massif, Italy) during the period 1975-2003. The Miage glacier developed the largest part of its debris cover over the last century, now found mostly between the glacier terminus (about 1850 m a.s.l.) and the upper ablation tongue (c. 2400 m a.s.l.) on a surface area of c. 4 km 2 The period examined (1975-2003) addresses climate conditions which were glacier-favourable (around the . 1980s), as well as glacier-unfavourable (since the early to mid-1990s), thus contributing to an understanding of the behaviour of debris covered glaciers under a changing climate. The analysis was based on the comparison between digital elevation models (DEMs), derived from historical records, specifically maps (1975; scale 1:10,000) and photogrammetric surveys (1991 and 2003, scale 1:15,000). The results show a general glacier volume loss (\u201316.640 x 10 6 m 3 ( from 1975 to 2003; nevertheless if we focus on the two time sub-windows (i.e.: 1975-1991 and 1991-2003) opposite trends are found: in the period 1975-1991 the volume variation of the Miage Glacier was about +19.25 710 6 m 3 , in the period 1991-2003, on the other hand, a volume decrease of about \u201336.2 710 6 m 3 occurred. Analysis shows that volume changes were strongly influenced by the supraglacial debris coverage which on Miage glacier tongue modulates the magnitude and rates of buried ice ablation

Glaciological characteristics of the ablation zone of Baltoro glacier, Karakoram, Pakistan

AbstractBaltoro glacier in the Karakoram, Pakistan, is one of the world's largest valley glaciers. It drains an area of about 1500 km2 and is >60km long. In 2004 an Italian/German expedition carried out a glaciological field program on the ablation zone of the glacier, focusing on the ablation conditions and the dynamic state of the glacier. As Baltoro glacier is a debris-covered glacier, ice ablation also depends on the debris properties. Stake measurements of ice ablation and debris cover in combination with meteorological data from automatic weather stations close by have been used to determine the local melt conditions. Results from these calculations have been combined with an analysis of different classes of surface cover and information about precipitation, using remote-sensing techniques, in order to calculate mass fluxes for the upper part of Baltoro glacier. The dynamic state of the glacier has been investigated by GPS-based surface velocity measurements along the stake network. A comparison of these short-term measurements during the melt season with surface velocities computed from feature tracking of satellite images shows a high seasonal variability of the ice motion. We have shown that this variability is up to 100% of the annual mean velocity. On the basis of these investigations, the mass fluxes at the Concordia cross-section have been quantified. This approach can now be used together with the ablation calculations to reconstruct the variability of glacier extent and volume in the past using available climate data from the central Karakoram. From the comparison of historical measurements and photographs it is shown that the snout of Baltoro glacier is oscillating back and forth a couple of hundred metres. Otherwise it seems not to react with the same magnitude as other glaciers to the climatic change. Elevation changes at Concordia are a few tens of metres at the most

Ice ablation and meteorological conditions on the debris-covered area of Baltoro glacier, Karakoram, Pakistan

AbstractDuring the recent Italian expedition 'K2 2004 – 50 years later' (June–July 2004) on Baltoro glacier, Karakoram, Pakistan, glaciological field experiments were carried out on the debris-covered area of this high-elevation glacier. The aim was to investigate the ice ablation and its relations with debris thermal properties and meteorological conditions. Ablation measurements along the glacier up to about 5000 m and within a dedicated test field were combined with meteorological data from two automatic weather stations located at Urdukas (4022 ma.s.l.) and at K2 Base Camp (5033 m a.s.l.). In addition, temperature measurements of the debris cover at different depth levels along the glacier allowed the calculation of debris surface temperature and of the debris thermal resistance (R). Using the air temperature, the local mean lapse rate (0.0075˚C m−1) and the measured ablation, the degree-day factors (K) at different locations on the glacier were calculated. The ice ablation rates were related to debris thickness and elevation. They are typically on the order of 4 cm d−1 during the observation period. However, it was found that the surface topography (slope, aspect) has an influence on the total ablation similar to that of the debris thickness. Thermal resistance of the debris cover and its distribution over the glacier were estimated. Finally, a best-guess estimate of the total meltwater production was calculated from available climate data

PRELIMINARY MAPPING OF GLACIERS AND GLACIAL LANDFORMS OF MOUNT AĞRI DAĞI (ARARAT), EASTERN ANATOLIA - TURKEY

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