Baltoro Glacier Research Articles

Ice velocity and climate variations for Baltoro Glacier, Pakistan

AbstractThe recent dynamic behaviour of Karakoram glaciers is expected to differ from that shown by glaciers in the central and eastern Himalaya because of regional variations in precipitation and temperature trends. However, there are insufficient quantitative data to support or confute such hypotheses. We present velocity data covering the period 1993–2008 for Baltoro Glacier, one of the longest glaciers in the Karakoram. Velocity measurements were made using cross-correlation feature tracking applied to European Remote-sensing Satellite (ERS-1 and -2) and Envisat advanced synthetic aperture radar (ASAR) data, supplemented by differential global positioning system (DGPS) measurements. We find a gradual acceleration of the glacier during the early 2000s, in particular during winter months. Multi-seasonal data reveal a large difference between summer and winter flow characteristics, but only in the upper ablation zone. Summer 2005 was a particularly dynamic period following from the heavy winter snowfall of 2004, indicating the importance of basal meltwater availability for glacier flow. Transverse velocity profiles indicate that Baltoro Glacier undergoes ‘block’ flow across much of the upper ablation zone during the summer, which we interpret as evidence of widespread basal sliding. The DGPS data confirm the rapid increase in flow detected during 2005. Modelled climatic data reveal decreasing summer temperatures and increasing precipitation over the study period, helping to explain the observed dynamic variations and their differences from glaciers elsewhere in the Himalaya.

Spatial distribution of debris thickness and melting from remote-sensing and meteorological data, at debris-covered Baltoro glacier, Karakoram, Pakistan

AbstractA distributed surface energy-balance study was performed to determine sub-debris ablation across a large part of Baltoro glacier, a wide debris-covered glacier in the Karakoram range, Pakistan. The study area is ~124km2. The study aimed primarily at analyzing the influence of debris thickness on the melt distribution. The spatial distribution of the physical and thermal characteristics of the debris was calculated from remote-sensing (ASTER image) and field data. Meteorological data from an automatic weather station at Urdukas (4022ma.s.l.), located adjacent to Baltoro glacier on a lateral moraine, were used to calculate the spatial distribution of energy available for melting during the period 1–15 July 2004. The model performance was evaluated by comparisons with field measurements for the same period. The model is reliable in predicting ablation over wide debris-covered areas. It underestimates melt rates over highly crevassed areas and water ponds with a high variability of the debris thickness distribution in the vicinity, and over areas with very low debris thickness (<0.03 m). We also examined the spatial distribution of the energy-balance components (global radiation and surface temperature) over the study area. The results allow us to quantify, for the study period, a meltwater production of 0.058 km3.

The recent evolution of Liligo glacier, Karakoram, Pakistan,and its present quiescent phase

AbstractLiligo glacier, in the central eastern Karakoram, Pakistan, is a small, south-to-north-flowing glacier situated in a transverse valley on the left (south) side of Baltoro glacier. New processing of satellite imagery enables a better quantification of terminus oscillations over the past 30 years. From the beginning of the 1970s to the beginning of the 21st century, Liligo glacier advanced about 2 km (60ma–1). The progress was characterized by a significant evolution of terminus morphology, similar to that observed on the same glacier during the advance event near the beginning of the 20th century, and to those of many other Karakoram glaciers. This suggests indications of a surge-type mechanism. Field observations performed in 2004 indicated there was probably no confluence at that time between Liligo and Baltoro glaciers and that a quiescent phase had started in the early years of the 21st century.

Onesnaženost ledenika Baltoro kot posledica turistične dejavnosti

Množične turistične aktivnosti v visokogorju povsod po svetu že kažejo negativne okoljske učinke. Na izbranem območju preučevanja, ledeniku Baltoro (Karakorum, Pakistan), je to predvsem pogled in/ali vzpon na drugo najvišjo goro na svetu - K2 (8611m) in okoliške gore. S terenskim delom na območju ledenika Baltoro smo ugotavljali vire onesnaževanja in stopnjo onesnaženosti širšega območja ledenika.

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.

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.

Liligo Glacier, Karakoram, Pakistan: a reconstruction of the recent history of a surge-type glacier

AbstractLiligo 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.

Shoshonitic and ultrapotassic post-collisional dykes from northern Karakorum (Sinkiang, China)

High-K calc-alkaline, shoshonitic and ultrapotassic post-collisional dykes of Neogene age have been found in the remote and little known region of northern Karakorum located around the Shaksgam valley, north of the K2-Gasherbrum range (China). The dykes derive from more or less comparable basic magma(s) and display rather unusual petrographic and geochemical characters with respect to the other K-rich rocks. The geochemical data are consistent with derivation of the basic magma(s) from small degrees of partial melting of garnet-lherzolites previously enriched in incompatible elements of crustal origin possibly during the subduction of the Indian plate beneath Karakorum. The spectrum of compositions reflects fractional crystallization governed by an early removal of clinopyroxene, phlogopite, plagioclase, garnet±amphibole followed by the precipitation of abundant alkali feldspar, amphibole±apatite±quartz. Additionally, assimilation of crustal rocks during magma ascent contributed to the unusual compositional characteristics and is suggested by the abundance of corroded quartz ( ± plagioclase) xenocrysts and by the occasional presence of granitic xenoliths. An apparent connection exists between magmatism and tectonism in the complex Karakorum Fault Zone (KFZ). It is suggested that, during the Neogene, the strike-slip KFZ and some adjacent post-metamorphic faults transiently behaved as extensional fault systems down to deep levels, triggering ascent and emplacement of the K-rich magma. The subsequent (re)activation of a compressive and transcurrent regime determined the rapid and recent uplift of the more primitive lamprophyres occurring in the plutonites and metamorphites of the upper Baltoro Glacier and K2-Gasherbrum range, relative to the more fractionated and contaminated lamprophyres injecting the shallower rocks of the Shaksgam valley area.

Zircon fission-track ages from the Gasherbrum Diorite, Karakoram Range, northern Pakistan

The Gasherbrum Peaks, in the Himalaya of Pakistan, reach elevations of >8000 m. The relief between the peaks and the adjacent valley (Baltoro Glacier) is in excess of 3000 m. Eight samples of the Early Cretaceous Gasherbrum Diorite at elevations between 4880 and 7165 m on Gasherbrum IV were collected for fission-track dating. Zircon fission-track ages from the Gasherbrum Diorite vary from Early Cretaceous to middle Tertiary in age. There is no consistent pattern between age and elevation. The Cretaceous ages indicate that these rocks were never deeply buried, i.e., heated to temperatures in excess of 175 C, to reset the zircons during Cenozoic time. These results also indicate that the uplift of this part of the Himalaya has been either very rapid and recent, or very slow since Early Cretaceous time. This latter possibility is not consistent with the high relief at Gasherbrum and what is known about regional tectonics. Gasherbrum IV zircons, currently at {approximately}4880 m, have never been at depths greater than 6 km, and less than 3 km of material has been removed from the top of the range by erosion since the Early Cretaceous. Rapid uplift has occurred very recently, and erosion rates have notmore » been able to keep pace with this uplift.« less

Emergency on the Karakoram Massif.

Sept 15, 1978. Urdukas Camp, Baltoro Glacier, K2. Jim is dying-each night he gets worse-more painful coughing (pleurisy) and increasing hemoptysis, so that I am afraid to anticoagulate him-respirations rising alarmingly and he can travel only a few paces uphill without going into paroxysms of bloody coughing.

Chogo Lungma Glacier, Karakoram

IWAS expecting in the autumn of 1954 to accompany as topographer the expedition of Dr. K. H rrligkofler, which had f r its objective Broad Peak in the upper Bal oro region. But during the summer months of that year the scientists of Professor Desio's successful K2 expedition had been at work on the Baltoro glacier, and I decided to go to another region of the Karakoram. I chose the Lungma glacier, which had only once before been investigated, and that half century ago. Although it is one of the very big valley-glaciers, Lungma is not situated in the zone of the main crest, but southwards at the bifurcation of the Rakaposhi and Haramosh ranges in the Lesser Karakoram. From Skardu on the Indus, itself only four days by air from Europe, the valley can now be reached by further four days* journey. The ease and relatively low cost of access may promote more activity by mountaineers and scientists in this region: last summer Frankfort Himalayan Ex? pedition went to Lungma, accompanied by the meteorologist Dr. Untersteiner. Easy access was also the reason that this glacier was the first of all the big Kara? koram glaciers to be discovered by European, G. T. Vigne in 1835.l He found the lower end a short distance from the village Arindo, the height of the ice wall there being nearly 100 feet. The next explorer was Godwin Austen in 18612 who wrote from the small village of Arundu at its (the * Loombah's) termination, its fields touching the ice. As these statements are still roughly accurate, it would seem that the length of the Lungma has not changed much during the last 120 years. However, although the glacier may not have changed much in its length, the thickness of the ice has varied greatly at different times. Godwin Austen carried out the first plane-table survey of this area in the space of only two days. But the result, part of his Sketch map of the glaciers of the Mustakh Range on scale of 1/506,880 (1 inch=8 miles), shows the form of Chogo Ganse much better than the map on 1/150,000 of the Workman expedition of 1903. This second map was based on theodolite survey by B. H. M. Hewett, corrected and supplemented by the authors (Fanny B. and William H. Workman) from actual observation and photographs. 7 They supposed, erroneously, that the given highest intersected point Indus-Nagar-Watershed-Peak No. (?Peak 46/42L=Malubiting) was fixed wrong during the Kashmir triangulation, as they thought Peak, which they had almost climbed to the top, was at least 300 feet higher than Malubiting. Meanwhile, during the triangulation of the Indo-Russian Connection Series in 1912/13 Malubiting (24,470 feet) was checked and found correct and new point was intersected: this was Peak 68/42L (23,056 feet) for which the Karakoram Conference Report suggests the name Yengutz Har, because of the glacier with this name on the northern side. 3 The peak which the Workmans tried to climb is really Yengutz Har. Oestreich had already made this suggestion,4 and last year's triangula? tion confirmed it. The Workmans' mistake was quite understandable; it is very easy to be wildly out when comparing the height of peaks without instruments. In fact Pyramid is 1400 feet lower than Malubiting, not 300 feet higher. Indeed many sketch-maps of this region are wrong, some even make 2 Siebentausender (peaks over 7000 metres or about 23,000 feet) out of one, partly as result of the many names existing for this mountain: Yengutz Har or is the same as Ghenish Chish (Burushaski for Gold Mountain) of the official quarter-inch map, and is the top of the ridge shown on Conway's map (1894) as the Golden Parri. The people of Arandu showed me the same peak as Spantik, probably because of highest single spot with grass at the foot of the south-eastern ridge of it (in Balti, s/>aw?=meadow, grass, tik =spot). If we follow the rule of the Karakoram Conference and call peaks,

Scientific Mountanineering in India 1

H R.H. the Duke of the Abruzzi undertook this expedition chiefly in the hope of con tributing to the solution of the vexed problem as to the greatest height which can he reached by moun taineers. But, as usual, he supplied him self with such a staff as would be able to make good use of every opportunity which his journey might afford for scien tific research. The basin of the Baltoro glacier was chosen for the attempt, owing to the number of high peaks at its head. K2 itself proved to be un climbable, in spite of several strenuous at tacks and much close reconnoitring, and on July i the Duke turned his attention to Bride Peak, 25,110 ft. Such were the unexpected difficulties encountered that it was not until July 10 that camp was pitched on Chogo Lisa Saddle, 20,784 ft. On July 12 a height of 23,458 ft. was attained, hut had weather forced them to retreat. On July 17 another start was made, and that evening they pitched their two diminutive MUmmery tents at 22,483 ft., the highest strictly authenticated camp to date, though Rubenson and Mon rad-Aas probably camped as high on Kabru.