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Contributions to the Antarctic Glaciology from India
R. Ravindra

Antarctica Division



Geological Survey of India, Faridabad.

Antarctica provides a unique environment to study the interactions of glaciation and climate without interferences of habitation, industry and pollution. Glaciological studies in Antarctica were initiated in 1982-83 by the First and Second Indian Antarctic Expeditions1-5 and most of these results were published by 1985. The initial observations recorded fluctuations of polar continental ice margin, ablation and accumulation patterns on the ice shelf, details of stratigraphic zonation within the shelf ice, melting rates on shelf ice during the polar day etc. In the subsequent expeditions, most of these studies were fine tuned and some long-term investigations were continued6-8.
As a part of the programme on monitoring fluctuations in continental ice margin, a prominent glacial tongue was identified in Western Schirmacher Range in 1983 and it was named Dakshin Gangotri Glacier Snout1. The snout was monitored from fixed survey points on an yearly basis9-10 and average annual recession rates were computed for this glacier. In 1996, many peripheral points were added along this snout to enhance the details of the observations11. Also, the advance and retreat patterns along the periphery of the glacier were recorded in every month during the wintering12. This established the overall model of recession of the glacier. Under the influence of global warming, huge ice shelves are breaking off; the evidence for such calving is available from the Antarctic coast. But the steady recession of this glacial tongue is a significant supportive evidence from an inland glacier13. These monthly trends were verified in the year 2000 by another prolonged observation during the wintering14 and the decadal rates of glacial recession were calculated. In 2001, the area of observation was increased by many km to cover the entire western wall of polar continental ice margin in Schirmacher Oasis. The succeeding years, till date, have shown that not only the snout of the glacier but the entire ice wall is strikingly receding. This uninterrupted observation for the last two decades is providing a valuable input for studying the impact of global warming in Antarctica.
Another long term project initiated in the Second Expedition2 was to record the ablation and accumulation patterns on the ice shelf. These observations have been carried out by fixing a network of stakes. These observations have continued on an yearly basis15-17 and sometimes details of monthly patterns are available from wintering teams also. The results of these observations have quantified the rate of ablation during polar summer (November to January) and the rate of accumulation during the polar winter (February to October). The average annual net accumulation18 on the ice shelf has also been calculated.
Antarctic ice sheet is an exceptional repository of the climatic record of the past thousands of years. The proxy indicators of palaeoclimatic records are preserved as air bubbles, gases, pollen, dust, volcanic particles, pollutants within the icy layers. To obtain this serial information, raising of ice cores is necessary. The initial attempts at recovery of ice cores were limited19-21 to the hand auger and the ice shelf. These cores provided useful information about isotopic composition of ice samples. First use of a motorized electromechanical drill22 was made in 1993 and in subsequent years, shallow ice core drilling (i.e. within a depth of 100 m) has been undertaken in many expeditions23-24. The analysis of these ice cores has provided useful insights about changes in the earth’s climate during the past two centuries25. All these drilling operations were carried out during the polar winter months. However, in 2003, ice core drilling was successfully tried during the polar summer (January-February) by going farther inland towards the Antarctic continental interior26. In addition to the isotopic analysis, these ice cores are being subjected to TL-dating processes.
The arrival of polar cold front induces significant changes in various ground media. In one of the earlier studies27, a comparative study of these thermal changes in ice, firn and permafrost was carried out. Based on these inputs, a more ambitious project was undertaken. A small glacier was drilled through its entire thickness till bedrock was encountered. Thermal sensors were placed from the surface of the glacier down to the bedrock-depths. These were monitored for one full year and it generated information about the effect of the polar cold front, its maximum penetration depth, response pattern within the layers of the glacier, the 10-m depth average annual temperature and thermal inversion point within the glacier28. Similar year-long thermal observations were also made in permafrost29 and information was gained about active layers of permafrost, penetration effect of polar cold front, penetration time lag within different layers of permafrost and annual trends of permafrost migration. By installation of automatic weather stations on ice shelf and on polar continental ‘blue’ ice, glacio-meteorological data was collected. Supporting these data with ground based observations, albedo studies were carried out, resulting in surface energy balance models for different snow and ice media30-32. During these studies, complementary data on snowdrift profiles, radiative properties of various media, micro-structural fabric of ice types was also collected33.
Geomorphological studies were initiated in the Fifth Expedition34 in the Wohlthat Mountains. These have been followed up in successive expeditions35-37. Various polar and peri-glacial landforms have been identified and characteristic diagnostic units have been mapped. Glacial debris and moraines of different generations have been plotted and sampled. After de-glaciation, the isostatic rebound has resulted in formation of raised beaches far above the present day coast38. The imprint of these glacial processes on the landscape provides inferences about peak glaciation, stages of its recession and the rate of recession39-41. The palaeo-paths and migration routes of glaciers over Schirmacher Oasis have been plotted42. The morainal samples are being probed by TL-dating methods and precise quantification of the stages of de-glaciation is expected soon. A geomorphological map of Schirmacher Oasis, incorporating these dates and details, is under preparation43.
Utilizing the modern precision instruments like the satellite based GPS, movement patterns, velocity, direction, stress of present day glaciers are being mapped44. Neo-tectonic features in Schirmacher Oasis are also being analyzed by these methods. GPS-based techniques have also been used in preparation of detailed topographic maps around Indian Antarctic Station, Maitri, which have been published45. In the coastal area of India Bay, hydrographic charts and ice shelf coastal delineation work has been carried out46. Antarctic coast-line is in a state of dynamic equilibrium and great chunks from floating ice shelf keep breaking off into the sea. Successive satellite imageries, for the past 30 years, have been utilized for studying the changing face of Antarctic coast-line near India Bay47.
There are numerous fresh water lakes in Schirmacher Oasis. These have been plotted on the map, genetically classified and each lake has been given a specific reference number48. Thermal variations within the lake waters have been studied49. Isotope analysis for some of the lake waters is also published50. Lake sediment coring has been carried out and palaeoclimatic models for changes in the Holocene, back to the last glacial maxima, have been made51-52. Fine resolution palynostratigraphic studies of lake sediments have provided insights to late Quaternary climatic cycles in the polar region53. Supraglacial sediments have also been studied for grain-size behaviour and morphoscopy using the SEM. Mechanical and chemical textural characteristics imprinted on these grains have been linked to the micro-environments and transportation agents54.
During the voyages to Antarctica and back, icebergs have been monitored from the ships. The first and last sighting of icebergs are marked. The concentration zones have been plotted, numbers have been counted, various sizes and shapes have been classified55. An attempt has been made to find out the relationship between global climatic change and iceberg sightings56.

References:


  1. Kaul, M.K., Chakraborty, S.K., and Raina, V.K. (1985): “A Note on the Snout of Dakshin Gangotri Glacier, Antarctica.” Scientific Report of the Second Indian Expedition to Antarctica, Tech Pub No. 2, DOD, New Delhi, pp 91-93.




  1. Kaul, M.K., Chakraborty, S.K., and Raina, V.K. (1985): “Ablation on the Antarctic Shelf Ice.” Scientific Report of the Second Indian Expedition to Antarctica, Tech Pub No. 2, DOD, New Delhi, pp 81-86.




  1. Kaul, M.K., Chakraborty, S.K., and Raina, V.K. (1985): “Stratigraphic Studies of Antarctic Ice.” Scientific Report of the Second Indian Expedition to Antarctica, Tech Pub No. 2, DOD, New Delhi, pp 99-102.




  1. Kaul, M.K., Chakraborty, S.K., and Raina, V.K. (1985): “Experiment on Artificial Augmentation of Ablation on the Shelf Ice, Antarctica.” Scientific Report of the Second Indian Expedition to Antarctica, Tech Pub No. 2, DOD, New Delhi, pp 95-97.




  1. Raina, V.K., Kaul, M.K., and Chakraborty, S.K. (1985): “Ice Shelf Studies at and around Indian Scientific Research Station, Dakshin Gangotri, Antarctica.” Scientific Report of the Second Indian Expedition to Antarctica, Tech Pub No. 2, DOD, New Delhi, pp 75-80.




  1. Kaul, M.K., Singh, R.K., Srivastava, D., Mukerji, S., and Jayaram, S. (1988): “Observations on the Changes in the Snout of Dakshin Gangotri Glacier, Antarctica.” Scientific Report of the Fifth Indian Expedition to Antarctica, Tech Pub No. 5, DOD, New Delhi, pp 205-209.




  1. Singh, R.K., Mukerji, S., Srivastava, D. and Kaul, M.K. (1988): “Snow Accumulation and Ablation Pattern on Ice Shelf near Dakshin Gangotri, Antarctica and Development of Face Ice off Dakshin Gangotri.” Scientific Report of the Fifth Indian Expedition to Antarctica, Tech Pub No. 5, DOD, New Delhi, pp 189-204.




  1. Ravindra, R., Dey, A., Beg, M.J. and Kaul, M.K. (1994): “Observations on the Snow Accumulation/Ablation over Shelf and Continental Ice in parts of Central Dronning Maud Land, East Antarctica.” Scientific Report of the Ninth Indian Expedition to Antarctica, Tech Pub No. 6, DOD, New Delhi, pp 227-238.




  1. D’Souza, M.J. and Kundu, A. (1998): “Glaciological Studies during the Seventeenth Antarctic Expedition: Monitoring of the Snout of Dakshin Gangotri Glacier.” Geol Surv Ind, Rec Vol 132, pt. 2, pp 67.




  1. Mukerji, S., Srivastava D., Singh, R.K. and Oberoi, L.K. (1999): “Glaciological Studies in Antarctica by Indian Scientific Expedition.” Proc Symp on Snow, Ice and Glaciers, Geol Surv Ind Spl Pub No. 53, pp 413-419.




  1. Chaturvedi, A., Singh, A., Gaur, M.P., Krishnamurthy, K.V. and Beg, M.J. (1999): “A Confirmation of Polar Glacial Recession by Monitoring the Snout of Dakshin Gangotri Glacier in Schirmacher Range.” Scientific Report of the Fifteenth Indian Expedition to Antarctica, Tech Pub No. 13, DOD, New Delhi, pp 321-336.




  1. Chaturvedi, A., Singh, A., Jayapaul, D., Asthana, R. and Ravikant, V. (1999): “Glaciological Studies carried out during the Wintering Period of XV Expedition and the Summer Period of XVI Indian Expedition to Antarctica.” Geol Surv Ind, Rec Vol 131, pt. 2, pp 71-74.




  1. Chaturvedi, A. and Ravindra, R. (2001): “Conspicuous Evidence of Global Warming from Schirmacher Range, Antarctica.” In Role of Earth Sciences in Integrated Development and Related Societal Issues, GSI-NR, Lucknow.




  1. Chaturvedi, A., Beg, M.J. and Prasad, A.V.K. (2004): “Monthly Patterns of Advance and Retreat Of Dakshin Gangotri Glacier Snout in Schirmacher Range.” Accepted for Pub in Scientific Report of the Nineteenth Indian Expedition to Antarctica, Tech Pub No. 17, DOD, New Delhi.




  1. Asthana, R., Gaur, M.P. and Chaturvedi, A. (1996): “Notes on Pattern of Snow Accumulation/Ablation on Ice Shelf and Secular Movement of Dakshin Gangotri Glacier Snout in Central Dronning Maud Land, East Antarctica.” Scientific Report of the Twelfth Indian Expedition to Antarctica, Tech Pub No. 10, DOD, New Delhi, pp 111-112.




  1. Beg, M.J., Chaturvedi, A., D’Souza, M.J. and Asthana, R. (1997): “Fluctuations in the Surface Profile of a part of Ice Shelf in Central Dronning Maud Land, East Antarctica.” Scientific Report of the Thirteenth Indian Expedition to Antarctica, Tech Pub No. 11, DOD, New Delhi, pp 221-226.




  1. Asthana, R., Gaur, M.P. and Dharwadkar, A. (2002): “Glaciological Studies during the Expedition.” Scientific Report of the Eighteenth Indian Expedition to Antarctica, Tech Pub No. 16, DOD, New Delhi, pp 95-109.




  1. Chaturvedi, A., Singh, A. and Beg, M.J. (1999): “Trend of Depositional Patterns on Ice Shelf near Dakshin Gangotri Station.” Scientific Report of the Fifteenth Indian Expedition to Antarctica, Tech Pub No. 13, DOD, New Delhi, pp 313-320.




  1. Nijampurkar, V.N., Bhandari, N., Bhattacharya, S.K., Rao, D.K., Sengupta, D., Raina, V.K. and Kaul, M.K. (1985): “Isotopic and TL Studies of Antarctic Ice Samples.” Scientific Report of the Second Indian Expedition to Antarctica, Tech Pub No. 2, DOD, New Delhi, pp 103-106.




  1. Nijampurkar, V.N., Bhattacharya, S.K., Mukerji, S., Singh, R.K. and Srivastava, D. (1988): “Oxygen Isotope Studies in Antarctica.” Scientific Report of the Fifth Indian Expedition to Antarctica, Tech Pub No. 5, DOD, New Delhi, pp 171-179.




  1. Nijampurkar, V.N., Rao, D.K., Kaul, M.K., Mukerji, S., Singh, R.K. and Srivastava, D. (1988): “Radioactivity Studies in Antarctica.” Scientific Report of the Fifth Indian Expedition to Antarctica, Tech Pub No. 5, DOD, New Delhi, pp 225-233.




  1. Chaturvedi, A. and Asthana, R. (1996): “An Attempt at Shallow Ice Core Drilling in Polar Continental Ice, Central Dronning Maud Land, Antarctica.” Scientific Report of the Twelfth Indian Expedition to Antarctica, Tech Pub No. 10, DOD, New Delhi, pp 77-99.




  1. Chaturvedi, A., Singh, A. and Kaul, M.K. (1999): “Ice-core Drilling in Polar Continental Ice at Tronstadhallet, Central Dronning Maud Land, Antarctica.” Proc Symp on Snow, Ice and Glaciers, Geol Surv Ind Spl Pub 53, pp 403-408.




  1. Chaturvedi, A., Singh, A. and Beg, M.J. (1999): Drilling for Polar Continental Ice Cores between Nunataks Veteheia and Tallaksenvarden in East Antarctica. Scientific Report of the Fifteenth Indian Expedition to Antarctica, Tech Pub No. 13, DOD, New Delhi, pp 281-302.




  1. Nijampurkar, V.N., Rao, D.K., Clausen, H.B., Kaul, M.K. and Chaturvedi, A. (2002): “Records of Climatic Changes and Volcanic Events in an Ice Core from Central Dronning Maud Land, East Antarctica, during the Past Century.” Proc Indian Acad Sci (Earth Planet Sci), Vol 111, No.1, pp 39-49.




  1. Ravindra, R. (2003): “Ice Core Drilling Programme.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed-N. Khare. pp 17.




  1. Chaturvedi, A. and Asthana, R. (1996): “A Study of Thermal Behaviour of Different Ground Media in Response to the Polar Cold Front in Antarctica.” Scientific Report of the Twelfth Indian Expedition to Antarctica, Tech Pub No. 10, DOD, New Delhi, pp 123-142.




  1. Chaturvedi, A. and Singh, A. (1999): “Thermal Variations within a Glacier from the Surface to the Bed-rock.” Scientific Report of the Fifteenth Indian Expedition to Antarctica, Tech Pub No. 13, DOD, New Delhi, pp 303-312.




  1. Chaturvedi, A., Singh, A. and Vekateswarlu, S. (1999): “Annual Cycle of Permafrost Migration in Schirmacher Oasis.” Scientific Report of the Fifteenth Indian Expedition to Antarctica, Tech Pub No. 13, DOD, New Delhi, pp 265-280.




  1. Srivastava, P.K. (2002): “A Comparative Study of Glacio-Meteorological Parameters, Reflectance and Surface Energy Exchange over Different Snow-Ice Media in Dronning Maud Land in East Antarctica.” Scientific Report of the Eighteenth Indian Expedition to Antarctica, Tech Pub No. 16, DOD, New Delhi, pp 153-190.




  1. Mishra, V.D. and Mathur, P. (2003): “Energy Budget Estimation based on Radiation Characteristics and Glacio-Meteorological Parameters of Different Snow-Ice Media in Antarctica through Ground Based and Automatic Weather Station Data and Study of Cracks using Ground Penetrating Radar.” Proc Nat Sem on India in Antarctic, Panjab University, Chandigarh. Ed- S. Chaturvedi.




  1. Kumar, M. (2004): “Albedo Studies in Antarctica.” Accepted for Publication in Scientific Report of the Nineteenth Indian Expedition to Antarctica, Tech Pub No. 17, DOD, New Delhi.




  1. Sharma, S.S. (2003): “Achievements of Snow and Avalanche Study Establishment in Antarctica.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed- N. Khare. pp 36-37.




  1. Srivastava, D., Kaul, M.K., Singh, R.K., Mukerji, S. and Jayaram, S. (1988): “Some Observations on the Glacial Geomorphological Features of Wohlthat Mountains, Central Queen Maud Land, Antarctica.” Scientific Report of the Fifth Indian Expedition to Antarctica, Tech Pub No. 5, DOD, New Delhi, pp 211-218.




  1. Ravindra, R., Pant, N.C. and D’Souza, M.J. (1991): “Landscape Evaluation of Humboldt and Adjacent Area, Wohlthat Mountains, East Antarctica.” Jour Geol Soc Ind, Vol 37, pp 172-183.




  1. Ravindra, R. and Dey, A. (1992): “Geological, Geomorphological and Glaciological Studies carried out during Austral Winter of 1990 at Antarctica.” Geol Surv Ind, Rec Vol 125, pt. 2, pp 99-101.




  1. Pant, N.C., Ravindra, R., and D’Souza, M.J. (1994): “Terminal Moraines in Grautfatet, Humboldt Mountain, East Antarctica: Indicators of Rate of Glacier Recession.” Scientific Report of the Ninth Indian Expedition to Antarctica, Tech Pub No. 6, DOD, New Delhi, pp 219-225.




  1. Ravindra, R. (1999): “Evidence of Raised Beaches from Schirmacher Oasis, East Antarctica.” IGCP-367 Meeting cum Workshop on Quaternary Coastal Environments: Records of Rapid Changes and Responses, Centre for Remote Sensing, Bharathidasan University, Tiruchirappalli, pp 27-28.




  1. Ravindra, R. (2001): “Geomorphology of Schirmacher Oasis, East Antarctica.” Proc Symp on Snow, Ice and Glaciers, Geol Surv India, Spl Pub No. 53, pp 379-390.




  1. Ravindra, R. (2001): “Geomophology of Schirmacher Oasis, East Antarctica.” Proc Symp Snow, Ice, and Glaciers, Geol Surv Spl Pub 53, pp 379-390.




  1. Gaur, M.P., Dharwadkar, A. and Asthana, R. (2002): “Glaciomorphic Landforms in parts of Schirmacher Oasis, Central Dronning Maud Land, East Antarctica.” Scientific Report of the Eighteenth Indian Expedition to Antarctica, Tech Pub No. 16, DOD, New Delhi, pp 81-93.




  1. Ravindra, R., Gaur, M.P., Chaturvedi, A., Beg, M.J. and Asthana, R. (2001): “Movement of Glaciers over Schirmacher Oasis during Last Glacial Maxima.” Pub in Role of Earth Sciences in Integrated Development and Related Societal Issues, GSI-NR, Lucknow.




  1. Ravindra, R. (2003): “Geological, Glaciological and Geomorphological Investigations in Central Dronning Maud Land, East Antarctica.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed- N. Khare. pp 15-16.




  1. Dhar, A. (2003): “Application of Global Positioning Systems for Crustal Deformation, Glaciology and Atmospheric Studies.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed- N. Khare. pp 86-87.




  1. Nagarajan, B. (2003): “Mapping Neo-tectonics and Geophysical Studies in Antarctica for Earth Science and Glaciology.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed- N. Khare. pp 23-24.




  1. Kumar, V. (2003): “Hydrographic Surveys in Antarctica using Ship Fitted Echosounder and GPS.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed- N. Khare. pp 25-26.




  1. Chaturvedi, A., D’Souza, M.J. and Ravindra, R. (2003): “Calving Pattern of Area Adjoining India Bay in Princess Astrid Coast, East Antarctica.” Accepted for Pub in National Seminar of Geol Soc Ind, National Centre for Antarctic and Ocean Research, Goa.




  1. Ravindra, R., Chaturvedi, A. and Beg, M.J. (2002): “Melt-water Lakes of Schirmacher Oasis Their Genetic Aspects and Classification.” Pub in Advances in Marine and Antarctic Science, New Delhi, Ed- D.B. Sahoo and P.C. Pandey, pp 301-313.




  1. Sinha, R., Chatterjee, A., Panda, A.K. and Mitra, A. (1999): “Thermal Structure and Heat Budget of Priyadarshini Lake, Schirmacher Oasis, East Antarctica.” Current Science, Vol 76, No. 5.




  1. Sinha, R., Navada, S.V., Chatterjee, A., Kumar, S., Mitra, A. and Nair, A.R. (2000): “Hydrogen and Oxygen Isotopic Analysis of Antarctic Lake Waters.” Current Science, Vol 78, No. 8.




  1. Bera, S.K. and Sinha, A.K. (2003): “Proxy Pollen Data Retrieved from Terrestrial Deposits in and around Schirmacher Oasis, East Antarctica.” Proc Nat Sem on India in Antarctic, Panjab University, Chandigarh. Ed- S. Chaturvedi.




  1. Bera, S.K. (2003): “Incidence of Airborne Palynodebris in Various Terrestrial Deposits and Lake Sediments in and around Schirmacher Oasis, East Antarctica: A Palaeoclimatic Approach.” Workshop on Research Programmes of Indian Antarctic Expeditions: Retrospect and Prospects. At National Centre for Antarctic and Ocean Research, Goa. Ed- N. Khare. pp 38-39.




  1. Bera, S.K. (2004): “Reconstruction of Palaeoclimate from Holocene Sequences of Lake Sediment, Schirmacher Oasis, East Antarctica.” Accepted for Pub in Scientific Report of the Nineteenth Indian Expedition to Antarctica, Tech Pub No. 17, DOD, New Delhi.




  1. Asthana, R. and Chaturvedi, A. (1998): “The Grain-size Behaviour and Morphoscopy of Supraglacial Sediments, South of Schirmacher Oasis, East Antarctica.” Jour Geol Soc Ind, Vol 52, pp 557-568.




  1. Gaur, M.P., Asthana, R., and Chaturvedi, A. (1996): “Monitoring of Icebergs in Antarctic Waters.” Scientific Report of the Twelfth Indian Expedition to Antarctica, Tech Pub No. 10, DOD, New Delhi, pp 101-109.




  1. Jayapaul, D., Chaturvedi, A. and Kaul, M.K. (2001): “A Study of Antarctic Icebergs and their Role as Indicators of Global Environmental Change.” Proc Symp Snow, Ice, and Glaciers, Geol Surv Spl Pub 53, pp 409-412.




  1. Ravindra, R. and Mitra, A. (2001): “Overview of the Geological Outputs of the Indian Antarctic Expeditions.” National Seminar on Precambrian Evolution and Mineralisation in India Its Economic Impact and Future Prospects. Seminar Volume, Ed. S.P. Singh, Patna.









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