ISRO Joins 36th Indian Scientific Expedition to Antarctica
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 for a long time. This year, in the 36th Indian scientific expedition, four teams from ISRO (one from Space Applications Centre (SAC) Ahmedabad with two members, one from National Remote Sensing Centre (NRSC) Hyderabad with four researchers, one from Indian Institute of Remote Sensing (IIRS) Dehradun with one scientist and one from Space Physics Laboratory(SPL) VSSC Thiruvananthapuram with three members) are participating.
Climate change is the thrust area of the 36th Indian Scientific Expedition to Antarctica (36-ISEA). The main objective of this expedition is to install stakes on ice for Differential Global Positioning System (DGPS) measurements around Bharati and Maitri to validate glacier surface velocity derived from satellite data to estimate thickness of snow over land and sea ice using Ground Penetrating Radars (GPR's) and also to verify conditions of snow over sea and land ice.
SAC is participating in the research activities in the area of Cryosphere under its Earth Observation Program. Cryospheric studies on the earth surface include the inventory, dynamics, changes, and interaction with hydrosphere, atmosphere etc., of snow, ice cover on land, sea ice and permafrost. The expedition team carried out helicopter based aerial surveys and collected data over the Antarctica ice-sheet, fast ice and sea ice floe. Bamboo stakes were installed over Polar Record glacier for measuring glacier surface ice velocity. The accurate coordinates of these stakes were recorded using DGPS. GPR data of various Antarctic ice features were collected at three different frequencies of 400 MHz, 500 MHz and 1GHz. It may be noted that 500 MHz GPR was indigenously developed by SAC.
Apart from collecting field data, the team at SAC also monitored sea ice status near Bharati and Maitri coasts of Antarctica using real time satellite data from newly launched SCATSAT-1 and other satellites, for accurate navigation of expedition ship.
Four researchers from NRSC are also participating in the 36-ISEA. Three of them have participated in voyage, carrying out scientific observations on board ship enrouted to Antarctica on green house gases and aerosols. The team have carried out measurements at Bharati and Maitri stations and also covering transaction between Bharati and Maitri station (about 3000 KM).
Following are the research activities in the area of climate change studies and Atmospheric studies:
- Study of snow melt/freeze dynamics in Antarctica using space based and ground based observations: Under ongoing project of NRSC, observations using snow fork were collected over six locations near Bharati station, Antarctica during November 2016 to January 2017. The observations included snow density, wetness and profile temperature in 26 pits dug on sheet ice.
- Measurements of Atmospheric Black Carbon (BC), GHGs and solar radiation fluxes at Antarctica on a long-term basis : The objectives of the project are to generate base line concentrations of atmospheric constituents such as CO2, CH4, H2O, which are being measured by ultra portable Greenhouse Gas Analyser/Licor CO2 analyser. BC measurement for long-range transport from populated mid and low latitude regions and its presence over pristine Antarctic environments is being measured using Aethalimeter-AE31. Microtops sun photometer is used to measure Columnar Aerosol Optical depth (AOD), Water vapour and Ozone.
- Image measurements of visibility to investigate atmospheric parameters : The objectives of the project are to estimate atmospheric visibility in horizontal and vertical (zenith) direction; estimation of atmospheric extinction in horizontal and vertical directions using CCD camera equipped with low power laser and laptop. CCD Camera is being used to get the contrast variation or quantifiable visibility, which in turn can be used to estimate the particulate matter over the Antarctica.
- Study on long term precipitation over Antarctica using surface and space-based measurements : The rate of atmospheric precipitation over Antarctica may have important role to global sea level variation via impact on the surface snow and ice accumulation. The objective of the project is to understand the inter-annual variability of precipitation by direct measurements of Antarctic precipitation features such as the frequency, the phase, and the snowfall rate and also validation of CloudSat satellite data retrievals of precipitation over Antarctica.
Study from IIRS includes “Validation of remote sensing and model based Antarctica Ice sheet features and glacier landforms”. Extensive field campaigns were conducted jointly with Geological Survey of India (GSI) in Wohlthat Mountains and Schirmacher oasis area near Mairti station during November 03, 2016 to February 24, 2017 as both studies have common objectives and study area.
SPL has conducted experiments in the areas of Polar Atmosphere and Polar Ionosphere. The scientific activities in the area of polar atmosphere include studies on atmospheric aerosols, chemistry, atmospheric boundary Layer, thermodynamics and coupling processes. These studies are carried out by making measurements of aerosol black carbon, by collecting snow and aerosol samples, balloon borne measurements of wind, temperature, humidity and ozone, measurement of boundary layer parameters using sonic anemometers as well as surface level measurements of various trace gases. In the area of Polar Ionosphere, studies are conducted to understand the impact of solar wind at the high and low latitude regions.
SCATSAT-1 2.25 km Data Derived Sea Ice cover over the Antarctica
The Data analysis shows the reduction of the sea ice in the India Bay region (information used as a part of sea ice advisory)
Snow Fork Observations in Pit