Abstract The glacier cover of the Hindu Kush Mountains of Afghanistan provides a natural laborato... more Abstract The glacier cover of the Hindu Kush Mountains of Afghanistan provides a natural laboratory to assess the impact of climate change on the cryosphere. However, to date, not much is known about how the cryosphere in these mountainous regions is responding to climate change. Therefore, using an integrated approach including geospatial technology, climate data, a mass balance study, as well as topographic analysis, we present the first systematic study of glacier fluctuations in the Kokcha sub-basin of the Afghanistan Range for the last 25 years (1990 to 2015). The glacier cover and the number of glaciers in the basin have reduced from 576 km2 and 1007 in 1990 to 492 km2 and 998 in 2015 respectively, losing ~84 km2 (~15%) of the total glaciated area. Besides the mass loss of the glaciers ranges from −0.65 m water equivalent per year and −0.02 m water equivalent per year with an average of −0.20 m water equivalent per year as estimated by the geodetic method. The equilibrium line altitude changes since the Late Pleistocene to the present vary from 810 ± 145 m to 1060 ± 145 m with an average of 722 ± 145 m. The increasing trend of temperature and shifting precipitation seasons have resulted in enhanced glacier recession and the formation of numerous glacial lakes in the basin. In addition to the climatic variables and glacier size, the topographic parameters slope, and elevation are observed to be the dominant factors influencing glacier recession and mass changes in the basin.
Abstract Paleoclimatic constraints from mountain ranges separating major climate systems are impo... more Abstract Paleoclimatic constraints from mountain ranges separating major climate systems are important in understanding past climatic changes. Using the present-day glacial geomorphology combined with the GlaRe model, the last glacial maximum (LGM) of seven representative valley glaciers of the Pir Panjal Range (PPR), Kashmir Himalaya was reconstructed. The Range lies at the interface of the tropical and temperate climates in the NW Himalayas. The glacier reconstructions showed that the glaciers in the Range advanced ~10 km down the present-day cirque margins and attained a thickness of more than 200 m during the LGM. Using six different methods, the equilibrium line altitude (ELA) changes in the selected valleys of the PPR were estimated for which the LGM was reconstructed. ELA depressions calculated for the LGM vary from 374 m to 416 m with a mean of 395 m. The weighted average ELA of the Range lies at an altitude of 3922 m a.s.l showing a general increasing trend from SE to NW of the Range. The published chronology of the loess deposits, a proxy for glacial aridity, shows the evidence of significant glacial advances starting around 350 kya in the valley, which is consistent with the evidence of both the pre- and post-LGM advances observed in this study. The presence of extensive glacier features all across the PPR and the presence of a few small heavily debris-covered glaciers in the Range points towards the rapid deglaciation in the area.
Environmental Monitoring and Assessment, Feb 24, 2017
Physico-chemical groundwater (GW) parameters were evaluated to understand the hydrogeochemical pr... more Physico-chemical groundwater (GW) parameters were evaluated to understand the hydrogeochemical processes in the Siwalik plains of Jammu and Kashmir, India. During the 2012-2013 post-monsoon (POM) and pre-monsoon (PRM) seasons, GW samples (n = 207) from deep bore wells and shallow open wells were chemically analysed. Cations (Ca 2+ , Mg 2+ , Na + , K + and Fe 2+) and anions (HCO 3 − , Cl − , SO 4 2− and F −) showed a wide spatio-temporal variation. Results suggest that weathering and dissolution of carbonates and silicate rocks is the main source of water mineralization. The major hydrochemical facies is characterized by Ca-Mg-HCO 3 and Ca-HCO 3 during the PRM and POM seasons respectively. The presence of sulphate-bearing water in a large number of the samples indicates a significant role of gypsum dissolution and anthropogenic contamination of the GW. Factor analysis (FA) and hierarchical cluster analysis (HCA) revealed that the variability of hydrochemistry is mainly related to rockwater interaction, dissolution of carbonates and other lithological units as well as the influence of anthropogenic activities in the area. Overall, it was found that the GW quality is within the limits of human consumption. The higher concentration of a few chemicals indicates an increasing trend of industrial contamination of the GW. For sustainable development of the portable GW in Siwaliks, it is necessary to minimize the adverse impacts of the anthropogenic and industrial contamination on the GW resources through best management practices and prevent its further contamination to a level that could make GW unsuitable for human uses.
Glacial-geomorphic studies provide vital information to make inferences about the effect of glaci... more Glacial-geomorphic studies provide vital information to make inferences about the effect of glacial advance and retreat on the geomorphology of an area. In the present study, glacial-geomorphic landforms of the Thajwas glacial valley in the upper reaches of the Indus, Kashmir Himalayas were mapped using geospatial technology validated with GPS-based field observations and ground photography. The glacial-geomorphic landforms were digitized using ASTER DEM (30 m resolution), Landsat ETMþ satellite imagery (30 m resolution) and Google Earth (1 m resolution) data. Results showed that Google Earth imagery, supported by field validation, is very useful for the interpretation of glacialgeomorphic landscapes and relief features at micro-and meso-scales. However, morphometric characteristics of landforms are best obtained using DEM overlaid onto the Landsat ETMþ satellite data. Glaciers in the valley are presently confined along the south and southwestern slopes. However, the significant role played by glaciers in shaping the geomorphic landforms and their subsequent preservation within the scenic landscape under the Late Quaternary climatic conditions are remarkably evident. The glacial-geomorphic landforms, especially terminal moraine, glacial trough and cirques observed in the valley aided the reconstruction of palaeo-glacial setting of the area. Morphology, shape and location of terminal and lateral moraine ridges were used to establish the palaeo-glacial extents, glacial volume and the number of glacial advances of the Thajwas glacier. The maximum elevation of the lateral moraines was used to define the former Equilibrium-Line Altitude (ELA). The greater rock excavation to form a large valley during the last glacial maximum might have induced isostatic rock uplift/exhumation in the glacier source area. It is observed that the concomitant retreat of the north-facing glacial cirques has played an important role in expanding the glacial valley and limiting the topographic relief.
The 2014 extreme flooding in Kashmir, with the peak discharge exceeding 115,000 cfs and the Jhelu... more The 2014 extreme flooding in Kashmir, with the peak discharge exceeding 115,000 cfs and the Jhelum River overflowing its banks, was triggered by the complex interplay of atmospheric disturbances causing widespread extreme rainfall for 7 days preceding the event. We used multisource data in GIS environment; satellites, hydro-meteorological, socioeconomic and field data, to assess the role of various factors in the flooding. The event was aggravated by the geomorphic setup of the Valley. Tributaries in the south, characterized by high gradient, decreased time of runoff concentration and increased flood peakedness with short lag, almost simultaneously discharge enormous volumes of floodwaters into the Jhelum around Sangam. Owing to the flat gradient of the Jhelum from Sangam downstream (<5 o), floods historically inundate vast areas in the stretch. The situation was exacerbated by the anthropogenic drivers, such as extensive urbanization of the floodplain, loss of wetlands, and decreased channel capacity due to the siltation from the deforested mountainous landscapes. The dilapidated flood control infrastructure and the institutional inability to manage the enormity of the event made the situation worst causing unprecedented damage to the infrastructure in the basin with the capital city Srinagar inundated up to »30ft for more than a week.
Abstract The ∼289 Ma Panjal Traps of NW India (Kashmir) are part of a series of rift-related mafi... more Abstract The ∼289 Ma Panjal Traps of NW India (Kashmir) are part of a series of rift-related mafic suites (Abor, Sikkim etc.) that were erupted onto northern India (present-day coordinates) around the same time as separation of the Cimmerian blocks of Qiangtang and Sibumasu. We report new data from only the second paleomagnetic investigation of this unit. Standard alternating field and thermal demagnetization methods were used to isolate characteristic magnetizations from seven outcrops at three locations within the Kashmir Valley, NW India. Analysis of four sections (14 individual cooling units) from close to Srinagar, that together form a tectonically coherent sequence spanning ∼3 km of stratigraphy, yield a single-component, primary magnetization with a mean direction of Dec: 134.8°, Inc: 55.3° ( α 95 = 8.9°, k = 21.0). An inclination-only mean of 52.5° ( α 95 = 8.9°, k = 47.2) gives a paleolatitude of ∼33°S (±5°). A paleopole of 110.5°E 8.4°S ( A 95 = 10.7) is also calculated. Assuming the magnetization records a portion of the reverse polarity Kiaman Superchron, the new result indicates extrusion of the Panjal Traps basalts at mid-latitudes in the southern hemisphere. By inference this constrains the location of central Gondwana, and informs debates related to Cimmeria’s detachment from Gondwana.
Rambiara River basin, a sub-basin of the Upper Indus, is dotted with fluvial and glacial geomorph... more Rambiara River basin, a sub-basin of the Upper Indus, is dotted with fluvial and glacial geomorphic landforms. The presence of large number of glacial landforms like moraines, cirques, aretes, U-shaped valleys, etc. reflects the enormous erosive power of the past glaciers. During the Last Glacial Maximum (LGM), glaciers on average were 200 m thick and extended more than 10 km from the present-day cirque marks. Rock glaciers outnumber the clean glaciers that cover an area of 0.22 and 1.25 km 2 , respectively, in the basin. Glacial lakes are the prominent features in the higher reaches of the basin and occupy an area ranging from 0.01 to 0.70 km 2. Downstream, the river is characterized by large channel width, anomalous sinuosity, braided pattern, and the presence of unpaired fluvial terraces. The large channel width depicts the enormous discharge from the glacial-and snow-melt during the Late Pleistocene when glaciers covered most of the Pir Panjal. After LGM, the glacier cover and the river discharge significantly decreased as highlighted by a large number of braided bars and the narrow stream to which the river is reduced. The warming trends observed across the Himalayas encompassing the Pir Panjal Range since the last century has further contributed significantly to the glacier recession in the basin.
TIn the last few decades Ponseti method has replaced soft tissue releases as the gold standard in... more TIn the last few decades Ponseti method has replaced soft tissue releases as the gold standard in the management of idiopathic clubfoot. However, the recurrence of the deformity is common without post tenotomy bracing. The purpose of this study was to retrospectively see various attributes of the patients associated with poor outcome after use of Ponseti method in idiopathic clubfoot management. Seventy nine consecutive patients with one hundred and twenty three idiopathic clubfeet treated with Ponseti method by single orthopaedic surgeon were followed for a period of two years and recurrence of the deformity was studied in relation to age of patient at presentation (< 3 months or more), sex of the patient, severity of the deformity ( moderate to severe verses (Vs.) very severe), compliance to post tenotomy bracing (compliant Vs. non compliant), educational level of parents (high school or less) and access of parents to internet (Yes or No) and odds ratio for recurrence and level...
The Srinagar reach of the River Jhelum in Kashmir Valley, India exhibits complex meandering and v... more The Srinagar reach of the River Jhelum in Kashmir Valley, India exhibits complex meandering and variable width (47-180m) and depth (0.76-6.09m). The reach is characterized by sharp bends in the river course, channel sinuosity, linearity of meander bends, linear truncation of braid-bars, and concavities and convexities in the river channel reflecting varied river geomorphic processes. During the extreme hydrological event of September 2014, alarge number of river breaches occurred along the river Jhelum, particularly in the Srinagar stretch of the river, due to the floodwaters overflowing the banks and the consequent bank erosion. The flooding situation was aggravated over the years by anthropogenic influences like the extensive urbanization of the Jhelum floodplains, encroachment of river banks and siltation of water courses due to the deforestation in the catchment and the shrinkage of wetlands which usually act as sponge during the flooding events. To establish a relationship between the geomorphic processes and anthropogenic activities on river morphology, we used various geomorphic parameters andtechniques like river profiling, bathymetric profiling, lateral entrenchment ratio, water velocity, sinuosity index, supported by GPS and other field measurements. The impact of the geomorphic and human induced changes on the channel morphology was corroborated with the data from the river breaches that occurred during the 2014 flooding, a few of which occurred at the locations where geological structures (lineaments/faults) cut across the river banks. Based on the investigations from this study, it is suggested that varied geomorphic processes and the unchecked anthropogenic activities in
Abstract The glacier cover of the Hindu Kush Mountains of Afghanistan provides a natural laborato... more Abstract The glacier cover of the Hindu Kush Mountains of Afghanistan provides a natural laboratory to assess the impact of climate change on the cryosphere. However, to date, not much is known about how the cryosphere in these mountainous regions is responding to climate change. Therefore, using an integrated approach including geospatial technology, climate data, a mass balance study, as well as topographic analysis, we present the first systematic study of glacier fluctuations in the Kokcha sub-basin of the Afghanistan Range for the last 25 years (1990 to 2015). The glacier cover and the number of glaciers in the basin have reduced from 576 km2 and 1007 in 1990 to 492 km2 and 998 in 2015 respectively, losing ~84 km2 (~15%) of the total glaciated area. Besides the mass loss of the glaciers ranges from −0.65 m water equivalent per year and −0.02 m water equivalent per year with an average of −0.20 m water equivalent per year as estimated by the geodetic method. The equilibrium line altitude changes since the Late Pleistocene to the present vary from 810 ± 145 m to 1060 ± 145 m with an average of 722 ± 145 m. The increasing trend of temperature and shifting precipitation seasons have resulted in enhanced glacier recession and the formation of numerous glacial lakes in the basin. In addition to the climatic variables and glacier size, the topographic parameters slope, and elevation are observed to be the dominant factors influencing glacier recession and mass changes in the basin.
Abstract Paleoclimatic constraints from mountain ranges separating major climate systems are impo... more Abstract Paleoclimatic constraints from mountain ranges separating major climate systems are important in understanding past climatic changes. Using the present-day glacial geomorphology combined with the GlaRe model, the last glacial maximum (LGM) of seven representative valley glaciers of the Pir Panjal Range (PPR), Kashmir Himalaya was reconstructed. The Range lies at the interface of the tropical and temperate climates in the NW Himalayas. The glacier reconstructions showed that the glaciers in the Range advanced ~10 km down the present-day cirque margins and attained a thickness of more than 200 m during the LGM. Using six different methods, the equilibrium line altitude (ELA) changes in the selected valleys of the PPR were estimated for which the LGM was reconstructed. ELA depressions calculated for the LGM vary from 374 m to 416 m with a mean of 395 m. The weighted average ELA of the Range lies at an altitude of 3922 m a.s.l showing a general increasing trend from SE to NW of the Range. The published chronology of the loess deposits, a proxy for glacial aridity, shows the evidence of significant glacial advances starting around 350 kya in the valley, which is consistent with the evidence of both the pre- and post-LGM advances observed in this study. The presence of extensive glacier features all across the PPR and the presence of a few small heavily debris-covered glaciers in the Range points towards the rapid deglaciation in the area.
Environmental Monitoring and Assessment, Feb 24, 2017
Physico-chemical groundwater (GW) parameters were evaluated to understand the hydrogeochemical pr... more Physico-chemical groundwater (GW) parameters were evaluated to understand the hydrogeochemical processes in the Siwalik plains of Jammu and Kashmir, India. During the 2012-2013 post-monsoon (POM) and pre-monsoon (PRM) seasons, GW samples (n = 207) from deep bore wells and shallow open wells were chemically analysed. Cations (Ca 2+ , Mg 2+ , Na + , K + and Fe 2+) and anions (HCO 3 − , Cl − , SO 4 2− and F −) showed a wide spatio-temporal variation. Results suggest that weathering and dissolution of carbonates and silicate rocks is the main source of water mineralization. The major hydrochemical facies is characterized by Ca-Mg-HCO 3 and Ca-HCO 3 during the PRM and POM seasons respectively. The presence of sulphate-bearing water in a large number of the samples indicates a significant role of gypsum dissolution and anthropogenic contamination of the GW. Factor analysis (FA) and hierarchical cluster analysis (HCA) revealed that the variability of hydrochemistry is mainly related to rockwater interaction, dissolution of carbonates and other lithological units as well as the influence of anthropogenic activities in the area. Overall, it was found that the GW quality is within the limits of human consumption. The higher concentration of a few chemicals indicates an increasing trend of industrial contamination of the GW. For sustainable development of the portable GW in Siwaliks, it is necessary to minimize the adverse impacts of the anthropogenic and industrial contamination on the GW resources through best management practices and prevent its further contamination to a level that could make GW unsuitable for human uses.
Glacial-geomorphic studies provide vital information to make inferences about the effect of glaci... more Glacial-geomorphic studies provide vital information to make inferences about the effect of glacial advance and retreat on the geomorphology of an area. In the present study, glacial-geomorphic landforms of the Thajwas glacial valley in the upper reaches of the Indus, Kashmir Himalayas were mapped using geospatial technology validated with GPS-based field observations and ground photography. The glacial-geomorphic landforms were digitized using ASTER DEM (30 m resolution), Landsat ETMþ satellite imagery (30 m resolution) and Google Earth (1 m resolution) data. Results showed that Google Earth imagery, supported by field validation, is very useful for the interpretation of glacialgeomorphic landscapes and relief features at micro-and meso-scales. However, morphometric characteristics of landforms are best obtained using DEM overlaid onto the Landsat ETMþ satellite data. Glaciers in the valley are presently confined along the south and southwestern slopes. However, the significant role played by glaciers in shaping the geomorphic landforms and their subsequent preservation within the scenic landscape under the Late Quaternary climatic conditions are remarkably evident. The glacial-geomorphic landforms, especially terminal moraine, glacial trough and cirques observed in the valley aided the reconstruction of palaeo-glacial setting of the area. Morphology, shape and location of terminal and lateral moraine ridges were used to establish the palaeo-glacial extents, glacial volume and the number of glacial advances of the Thajwas glacier. The maximum elevation of the lateral moraines was used to define the former Equilibrium-Line Altitude (ELA). The greater rock excavation to form a large valley during the last glacial maximum might have induced isostatic rock uplift/exhumation in the glacier source area. It is observed that the concomitant retreat of the north-facing glacial cirques has played an important role in expanding the glacial valley and limiting the topographic relief.
The 2014 extreme flooding in Kashmir, with the peak discharge exceeding 115,000 cfs and the Jhelu... more The 2014 extreme flooding in Kashmir, with the peak discharge exceeding 115,000 cfs and the Jhelum River overflowing its banks, was triggered by the complex interplay of atmospheric disturbances causing widespread extreme rainfall for 7 days preceding the event. We used multisource data in GIS environment; satellites, hydro-meteorological, socioeconomic and field data, to assess the role of various factors in the flooding. The event was aggravated by the geomorphic setup of the Valley. Tributaries in the south, characterized by high gradient, decreased time of runoff concentration and increased flood peakedness with short lag, almost simultaneously discharge enormous volumes of floodwaters into the Jhelum around Sangam. Owing to the flat gradient of the Jhelum from Sangam downstream (<5 o), floods historically inundate vast areas in the stretch. The situation was exacerbated by the anthropogenic drivers, such as extensive urbanization of the floodplain, loss of wetlands, and decreased channel capacity due to the siltation from the deforested mountainous landscapes. The dilapidated flood control infrastructure and the institutional inability to manage the enormity of the event made the situation worst causing unprecedented damage to the infrastructure in the basin with the capital city Srinagar inundated up to »30ft for more than a week.
Abstract The ∼289 Ma Panjal Traps of NW India (Kashmir) are part of a series of rift-related mafi... more Abstract The ∼289 Ma Panjal Traps of NW India (Kashmir) are part of a series of rift-related mafic suites (Abor, Sikkim etc.) that were erupted onto northern India (present-day coordinates) around the same time as separation of the Cimmerian blocks of Qiangtang and Sibumasu. We report new data from only the second paleomagnetic investigation of this unit. Standard alternating field and thermal demagnetization methods were used to isolate characteristic magnetizations from seven outcrops at three locations within the Kashmir Valley, NW India. Analysis of four sections (14 individual cooling units) from close to Srinagar, that together form a tectonically coherent sequence spanning ∼3 km of stratigraphy, yield a single-component, primary magnetization with a mean direction of Dec: 134.8°, Inc: 55.3° ( α 95 = 8.9°, k = 21.0). An inclination-only mean of 52.5° ( α 95 = 8.9°, k = 47.2) gives a paleolatitude of ∼33°S (±5°). A paleopole of 110.5°E 8.4°S ( A 95 = 10.7) is also calculated. Assuming the magnetization records a portion of the reverse polarity Kiaman Superchron, the new result indicates extrusion of the Panjal Traps basalts at mid-latitudes in the southern hemisphere. By inference this constrains the location of central Gondwana, and informs debates related to Cimmeria’s detachment from Gondwana.
Rambiara River basin, a sub-basin of the Upper Indus, is dotted with fluvial and glacial geomorph... more Rambiara River basin, a sub-basin of the Upper Indus, is dotted with fluvial and glacial geomorphic landforms. The presence of large number of glacial landforms like moraines, cirques, aretes, U-shaped valleys, etc. reflects the enormous erosive power of the past glaciers. During the Last Glacial Maximum (LGM), glaciers on average were 200 m thick and extended more than 10 km from the present-day cirque marks. Rock glaciers outnumber the clean glaciers that cover an area of 0.22 and 1.25 km 2 , respectively, in the basin. Glacial lakes are the prominent features in the higher reaches of the basin and occupy an area ranging from 0.01 to 0.70 km 2. Downstream, the river is characterized by large channel width, anomalous sinuosity, braided pattern, and the presence of unpaired fluvial terraces. The large channel width depicts the enormous discharge from the glacial-and snow-melt during the Late Pleistocene when glaciers covered most of the Pir Panjal. After LGM, the glacier cover and the river discharge significantly decreased as highlighted by a large number of braided bars and the narrow stream to which the river is reduced. The warming trends observed across the Himalayas encompassing the Pir Panjal Range since the last century has further contributed significantly to the glacier recession in the basin.
TIn the last few decades Ponseti method has replaced soft tissue releases as the gold standard in... more TIn the last few decades Ponseti method has replaced soft tissue releases as the gold standard in the management of idiopathic clubfoot. However, the recurrence of the deformity is common without post tenotomy bracing. The purpose of this study was to retrospectively see various attributes of the patients associated with poor outcome after use of Ponseti method in idiopathic clubfoot management. Seventy nine consecutive patients with one hundred and twenty three idiopathic clubfeet treated with Ponseti method by single orthopaedic surgeon were followed for a period of two years and recurrence of the deformity was studied in relation to age of patient at presentation (< 3 months or more), sex of the patient, severity of the deformity ( moderate to severe verses (Vs.) very severe), compliance to post tenotomy bracing (compliant Vs. non compliant), educational level of parents (high school or less) and access of parents to internet (Yes or No) and odds ratio for recurrence and level...
The Srinagar reach of the River Jhelum in Kashmir Valley, India exhibits complex meandering and v... more The Srinagar reach of the River Jhelum in Kashmir Valley, India exhibits complex meandering and variable width (47-180m) and depth (0.76-6.09m). The reach is characterized by sharp bends in the river course, channel sinuosity, linearity of meander bends, linear truncation of braid-bars, and concavities and convexities in the river channel reflecting varied river geomorphic processes. During the extreme hydrological event of September 2014, alarge number of river breaches occurred along the river Jhelum, particularly in the Srinagar stretch of the river, due to the floodwaters overflowing the banks and the consequent bank erosion. The flooding situation was aggravated over the years by anthropogenic influences like the extensive urbanization of the Jhelum floodplains, encroachment of river banks and siltation of water courses due to the deforestation in the catchment and the shrinkage of wetlands which usually act as sponge during the flooding events. To establish a relationship between the geomorphic processes and anthropogenic activities on river morphology, we used various geomorphic parameters andtechniques like river profiling, bathymetric profiling, lateral entrenchment ratio, water velocity, sinuosity index, supported by GPS and other field measurements. The impact of the geomorphic and human induced changes on the channel morphology was corroborated with the data from the river breaches that occurred during the 2014 flooding, a few of which occurred at the locations where geological structures (lineaments/faults) cut across the river banks. Based on the investigations from this study, it is suggested that varied geomorphic processes and the unchecked anthropogenic activities in
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