Survey of India, the premier mapping agency of India, has been associated with Indian Antarctica Research Program since the 10th Indian Scientific Expedition to Antarctica (1991-92). It has been taking part in all the expeditions ever since, except for the 15th expedition. The focus till the 22nd expedition has remained to carry out the surveying and mapping of the entire Antarctica region of Indian interest and provide additional technical support to the various other participating agencies. During the first two expeditions, global positioning system (GPS) and conventional triangulation techniques were used for providing primary control work to facilitate detailed mapping of the area using conventional mapping techniques. In the successive expeditions, initially, mapping was done on the scale of 1:5000 with contour interval 5m and then on a scale of 1:1000 with a contour interval of 1m. 7.8 sq. km of Schirmacher Oasis has been surveyed, and mapping has been undertaken on a large scale. Analogue and digital maps have been prepared for most of the areas for scientific use.
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Antarctica has become an essential region of International Cooperation in scientific research governed by the norms of the International Treaty (Wikipedia, n.d.). India started research in Antarctica with the first scientific expedition to Antarctica in 1981-82. The initial days of Indian scientific efforts in Antarctic science were challenging and required herculean tasks to start from scratch. Therefore, the Indian mapping and survey in the Antarctic region during the first three decades are essential and historical. The present chapter details those significant scientific efforts made in the initial about 30 years.
The Survey of India began participating in the research at Antarctica during the 10th Indian Scientific Expedition. Survey of India has been continuously participating in research work in Antarctica, except for the 15th Indian Scientific Expedition to Antarctica (Survey of India, Annual Report 2011-12). Primary control points have been established in Schirmacher Oasis during the 10th Antarctica Expedition for mapping and other scientific studies in the region.
Survey of India has established Geodetic and Geophysical Control in Schirmacher Oasis and its surroundings for future scientific explorations in glaciology and global change. It has provided control points for the Dakshin Gangotri Glacier snout for the Geological Survey of India, control points for the observatory of the India Meteorological Department. It has also aided survey work related to the National Physical Laboratory, Defence Electronics Application Laboratory and National Environmental Engineering Research Institute.
It was felt that, before starting any mapping activities in a region, there is a need for height control for subsequent mapping to establish planimetric and location-based research activities. GPS (British Antarctic Survey, n.d.) was used during the 10th expedition to select 14 planimetric control points in Schirmacher Oasis and surrounding nunataks. The heights of the stations were established by connecting the actual sea level from two different locations in the sea through GPS observations. In addition to geomagnetic, gravity measurements were also taken on all control points established through GPS techniques because the GPS observations properly represent the ongoing crustal movement in the Antarctic Region (Ohzono et. al., 2006) All these activities were carried out given providing primary control and further studies for crustal movement or Glacier Movement. It was emphasized by the scientific community that there is a need for a large-scale map around the Maitri station for other developmental activities. During the 11th and 12th expeditions, a map was prepared on a scale of 1: 5,000 using Total Station along with conventional techniques. GPS control work was also extended up to that region. Mapping at 1:1000 for Schirmacher Oasis at a contour interval of 1m was undertaken during the 13th to 21st expedition. Due to specific reasons, the mapping could not be carried out during the 15th & 17th expeditions. The large-scale map was thought to be very useful for other scientific activities like Environmental studies, Soil studies, Crustal Movement Studies and other Atmospheric Parametric studies (Tropospheric and Ionospheric). In addition to mapping, the Survey of India team also carried out a Glacier Movement Study in Dakshin Gangotri glacier and glaciers located around Schirmacher Oasis and Geological Survey of India.
During the 16th expedition (Rawat & Mehta, 2000), the Survey of India team assisted the Norway Geodetic team in carrying out GPS observation at Maitri Station to provide a control point for their use.
During the 17th expedition (Ravichandran, 2000), a new GPS Bench Mark MAII was established near Maitri on the hilltop, adjoining its eastern side of the Priyadarshni (ZUB) lake. Survey of India, NGRI, and Institute of Planetary Geodesy University have jointly taken up the study of Planetary Geodesy in Antarctica to study the plate movement of Antarctica concerning other plates and to understand Ice-Shelf dynamics.