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elevation

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    Liligo Glacier is a small glacier located in a transverse valley, which flows on the south side of Baltoro Glacier, Karakoram, Pakistan. Terminus variations of Liligo Glacier since 1892 were reconstructed using various methods and sources (historical documents, cartography, photographs, satellite images and field surveys). The glacier is characterized by two phases of strong advance (beginning and end of the 20th century), separated by at least half a century of retreat. The advance rates, together with some ice-surface features such as the heavily crevassed surface and terminus morphology, are considered to be indicative of a surge-type glacier.

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    Baltoro glacier in the Karakoram, Pakistan, is one of the world’s largest valley glaciers. It drains an area of about 1500km2 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

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    During 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 5000m and within a dedicated test field were combined with meteorological data from two automatic weather stations located at Urdukas (4022ma.s.l.) and at K2 Base Camp (5033ma.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 (0.00758 K/m) 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 4cm/ day 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.

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    This book is directly derived from a NATO-sponsored international meeting on problems of high altitude medicine and biology, which was held on the shores of lake of Issyk-Kul, in Kyrghyzstan, in June 5-6, 2006. The meeting was remarkable by several aspects. The participants enjoyed the beauty of the blue waters of this 1610 m high sacred lake, with stunning view on the Tien Shan mountain range at a distance, and, most of all, the wonderful Kyrghyz hospitality and friendship. It was a surprise for several European and North and South-American scientists to discover the still on-going momentum high level altitude physiology research, which was extremely active but insufficiently acknowledged in this remote Central Asian country at the time of the USSR. Accordingly, the setting was perfect for numerous positive scientific interactions, exchanges of ideas, and structuring of new international collaborations. Overall, the meeting was an ideal mix of cell biology, integrative physiology and medical applications. Thanks to the efforts of both English and Russian speaking scientist participants, this comes out very well in this book. Hypoxia is and remains a major public health issue in many populated mountainous areas all over the world. We are sure that this book will be become a long-lasting essential reference.

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    Assessment of the presence and severity of acute mountain sickness (AMS) is based on subjective reporting of the sensation of symptoms. The Lake Louise symptom scoring system (LLS) uses categorical variables to rate the intensity of AMS-related symptoms (headache, gastrointestinal distress, dizziness, fatigue, sleep quality) on 4-point ordinal scales; the sum of the answers is the LLS self-score (range 0–15). Recent publications indicate a potential for a visual analogue scale (VAS) to quantify AMS. We tested the hypothesis that overall and single-item VAS and LLS scores scale linearly. We asked 14 unacclimatized male subjects [age 41 (14), mean (SD) yr; height 176 (3)?cm; weight 75 (9)?kg] who spent 2 days at 3647?m and 4 days at 4560?m to fill out LLS questionnaires, with a VAS for each item (i) and a VAS for the overall (o) sensation of AMS, twice a day (n?=?172). Even though correlated (r?=?0.84), the relationship between LLS(o) and VAS(o) was distorted, showing a threshold effect for LLS(o) scores below 5, with most VAS(o) scores on one side of the identity line. Similar threshold effects were seen for the LLS(i) and VAS(i) scores. These findings indicate nonlinear scaling characteristics that render difficult a direct comparison of studies done with either VAS or LLS alone

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    Peribronchial edema has been proposed as a mechanism enhancing airway responses to constrictor stimuli. Acute exposure to altitude in nonacclimatized lowlanders leads to subclinical interstitial pulmonary edema that lasts for several days after ascent, as suggested by changes in lung mechanics. We, therefore, investigated whether changes in lung mechanics consistent with fluid accumulation at high altitude within the lungs are associated with changes in airway responses to methacholine or exercise. Fourteen healthy subjects were studied at 4,559 and at 120 m above sea level. At high altitude, both static and dynamic lung compliances and respiratory reactance at 5 Hz significantly decreased, suggestive of interstitial pulmonary edema. Resting minute ventilation significantly increased by ?30%. Compared with sea level, inhalation of methacholine at high altitude caused a similar reduction of partial forced expiratory flow but less reduction of maximal forced expiratory flow, less increments of pulmonary resistance and respiratory resistance at 5 Hz, and similar effects of deep breath on pulmonary and respiratory resistance. During maximal incremental exercise at high altitude, partial forced expiratory flow gradually increased with the increase in minute ventilation similarly to sea level but both achieved higher values at peak exercise. In conclusion, airway responsiveness to methacholine at high altitude is well preserved despite the occurrence of interstitial pulmonary edema. We suggest that this may be the result of the increase in resting minute ventilation opposing the effects and/or the development of airway smooth muscle force, reduced gas density, and well preserved airway-to-parenchyma interdependence.

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    In the Sagarmatha National Park, Nepal, Himalayan species of Galliformes are poorly studied and their present status is unknown. We studied the distribution of three high-altitude species: Himalayan monal, blood pheasant, and Tibetan snowcock, comparing birds' distribution in relation to altitude and habitat in spring and autumn 2007. Our study area was at 3300–5000 m a.s.l., characterized by subalpine vegetation. A structural description of vegetation types was made on the basis of main habitat features. We observed two different patterns across the year. Group size differences are common during spring and autumn. Variation in habitat use and altitudinal ranges are evident in the snowcock and blood pheasant. The Himalayan monal distribution was influenced by anthropogenic resources.

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    The lungs play a pivotal role in adaptation to high altitude. The increase in ventilation and the rise in pulmonary artery pressure are the first features of lung response to hypoxic exposure. At high altitude the lungs can also be affected by high-altitude pulmonary oedema, a severe form of acute mountain sickness. In healthy subjects the ascent to high altitude is also associated with alterations in lung function, which have been in part interpreted as an effect of extra vascular lung fluid accumulation. The patterns of respiratory function changes at high altitude are discussed, taking into account the body fluid movement and the increase in endothelial permeability induced by hypoxic exposure. As the problem of “respiratory” patients at high altitude is very important, a short summary of the guidelines for altitude exposure of asthmatic and COPD patients is reported at the end of the chapter.

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    Special Issue: Methodologies and Tools for the Management of Mountain Protected Areas: Mount Everest (Nepal, China) and K2 (Pakistan) Regions.

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    The aim of this contribution is to present the research activities which will be carried out in the frame of the Project “Institutional Consolidation for the Coordinated and Integrated Monitoring of Natural Resources towards Sustainable Development and Environmental Conservation in the Hindu Kush - Karakoram-Himalaya Mountain Complex”. The Project will be performed within the cooperation of four scientific partners: IUCN (International Union for the Conservation of Nature and Natural Resources), ICIMOD (International Centre for Integrated Mountain Development), Ev-K2-CNR and CESVI (NGO, Cooperazione e Sviluppo, onlus) with the involvement of international researchers. The local management will be provided in Nepal by the Sagarmatha National Park (SNP), in Pakistan by the Central Karakoram National Park (CNKP) and in Tibet Autonomous Region (China) by the Quomolongma Nature Preserve (QNP). This contribution will provide an overview about the research issues (on forests, biodiversity, glacier changes, livelihoods) mainly based on remote sensing technologies which could be successfully applied on CNKP. The need for integrating remote sensing data and field activities are presented as well. The applied image processing techniques (i.e. radiometric normalization, image geometric rectification and thematic classification) are introduced with an emphasis on the key role played by acquiring field data and evaluating the accuracy. The basis of this discussion is the creation of some base thematic maps realised mainly from remote sensing data.