ISRO's Participation in Antarctic Expedition
The National Centre for Antarctic and Ocean Research (NCAOR), Ministry of Earth Sciences, Government of India, organises the Indian Scientific Mission to Antarctica every year and ISRO has been participating in it for a long time. This year, in the 35th Indian scientific expedition, ISRO participated with three projects - one on-going project from Space Application Centre (SAC) and two new projects from National Remote Sensing Centre (NRSC). During the expedition, the project team collected ground data to interpret and validate the satellite images and also installed instruments for the measurement of green-house gases and atmospheric black carbon during Austral summer (November 2015-March 2016).
Antarctica ice sheets play an important role in influencing the climate system. Global climate change has a great impact on the ice shelves because they are sensitive to changes in air and ocean temperature or circulation near Antarctica. Extensive work on this has been done in the past by ISRO scientists; the latest studies during the 35th Indian scientific expedition are described below:
- SAC collected ground observations near Bharati and Maitri stations using indigenously developed Ground Penetrating Radar (GPR) of 500 MHz. GPR data was collected at seventeen locations on Ice Sheet, Ice Shelf, Iceberg and Sea Ice etc. GPR penetrated through almost the entire observed thickness of Sea Ice, found to be around 2 meters, which is consistent with the field. The GPR data could also provide the thickness of top stratigraphic layers over Ice Shelves, Icebergs and Ice Sheets.
- SAC/ISRO is also providing near real time Sea Ice advisory to NCAOR since 2012, using data from Indian satellites, namely, RISAT, Resourcesat-2, AWiFS, LISS-III, LISS-IV, Saral-Altika and foreign satellite data and products. This helps in safer ship navigation through Sea Ice portion of Antarctica.
- Towards the measurement of atmospheric Black Carbon (BC), Green House Gases and Solar Radiation Fluxes at Antarctica on a long term basis, NRSC has installed Atmospheric CO2 Sensor at Bharati station and also measured total Ozone during ship voyage.
- NRSC also participated to Study the snow melt/freeze dynamics in Antarctica and Sea Ice characterisation using space based and ground based observations. To understand melt/freeze dynamics and its response to microwave remote sensing data, snow properties were collected using GPR (200 MHz and 400 MHz) and Snow Fork (Density and Wetness) near Bharati and Maitri Stations. GPR profiles were collected on 5 routes over ocean to measure Sea Ice thickness and on 10 locations over Sheet Ice.
- Snow density and wetness observations using snow fork were collected on 13 days and 20 pits were dug with a maximum snow depth of 1.2 m.
Spatio-temporal dynamics of surface melting over Antarctica using scatterometer data from OSCAT on-board Oceansat-2 and QuikSCAT are available under NICES programme on Bhuvan portal
…Contd (Antarctica Ground Station)
A View of Bharati Station, Antarctica
A View of Maitri Station, Antarctica
Sea Ice measurement with GPR at Quilty Bay
(1:Air-Snow interface, 2: Snow-Sea ice interface, 3-next strong reflection)
GPR Measurement on Iceberg
Atmospheric CO2 Sensor at Bharati Station NRSC
Measurement of Total Ozone during Ship Voyage
GPR Observations over Sea Ice
Snow Fork Observations