Remote Sensing is defined as the science of techniques of getting about an object without coming in its physical contact. The basis of the remote sensing is the electromagnetic radiations or light which gives the information about the characteristics of the radiation, interaction with the object, internal structure of the object and reflectance/emittance of the radiations induce a particular signature or characteristics of the object which helps in identifying the particular object. Every object has its own signature i.e. reflectance properties.
Like different minerals, rock, soils, plant, etc have their own reflectance which helps in identifying that particular object. There are two types of satellites- remote sensing/sunsynchrous and geostationary satellites. The satellites which orbit from north pole to south pole are called remote sensing satellites and these satellites are used for mapping of natural resources and helps in other applications.
As these satellites orbit from north pole to south pole, these view the whole earth and helps in monitoring the whole earth either for natural resources mapping or disaster monitoring. The first remote sensing satellite was launched by United States of American in 1972 and called as LANDSAT. Later on, other countries have made their own satellites and launched in orbit for multiple applications. India had launched its first remote sensing satellite in 1988 named as ITS-1A. Later on India has launched many satellites having very good resolution like Cartosat-2 having 80cm resolution.
India is one of the leading countries in the world having the capability of launching and manufacturing the satellites. After the mission Chandryan-1, it becomes the fourth country in the world who has the capability to launch missions on other planets. The geostationary satellite are those which have the same rotation period as per the earth and hence stationary with respect to the earth and launched on equator of the earth at the height of 36000 Km. These satellites are helpful in communication and weather forecasting. As the rotation period is same as per earth, these satellites view the same region of the earth.
INSAT series of satellites of India are geostationary satellites. The geographical information system (GIS) is a computer based technique of handling huge amount of data which can be stored, retrieved and edited as and when desired.
2.0 Applications of Remote Sensing and GIS
There are number of applications of remote sensing and GIS in different fields. Some of the major applications of remote sensing and GIS are in the following areas.
(2.1) Agricultural/Acreage Forecasting
The satellite data are unbiased and give true information of land features. The repetivity, spectral differentiation, spatial resolution are some of the useful characteristics of satellite data which helps in forecasting of acreage in rabi and kharif seasons and these types of studies are very useful for estimating the production in particular seasons for particular crop.
(2.2) Geology/Mineral Resources
Satellite data are highly useful in geological mapping and targeting new mineral deposits. Based on spectral signatures of minerals and rocks, new mineral deposits can be mapped. Geological mapping especially in unapproachable areas can be easily mapped with the help of satellite data.
(2.3) Environmental Studies
The environmentally degraded lands/areas, water quality problem areas, pollution zones, point and line pollution sources can be mapped with the help of satellite data. The dangered ecological zones mapping, degradation zones, possible environmental impacts, degradation causes can be studied with the help of satellite data and geographical
(2.4) Disaster Management
Disasters can be monitored through satellite data and suitable management steps can be taken in effected areas. Satellite data and GIS can be used in mapping of disaster prone zones in an area and very helpful in mitigation of disasters. The digital elevation model helps in understanding of proper flow path of flood water. Drought can be monitored and necessary mitigation steps can be taken to combat the ill effects.
(2.5) Civil Engineering
Satellite data are highly useful in delineating sites for suitable road, railway, bridge and other engineering structures. The unapproachable terrain can be seen on satellite data and planning can be done. The sites for habitation, soil types, geological easily be mapped and monitored through satellite data.
(2.6) Water Resources
Satellite data are highly useful in delineating suitable groundwater prospects zones based on geology, geomorphology, lineament, drainages, land use patterns helps in delineating the groundwater prospects in the area. The river basins, watershed management and surface water bodies can be easily done based on satellite data.
Satellite data are highly useful in studying forest coverage in area. In unapproachable areas especially in dense and high altitude areas, remote sensing satellite data are highly useful for assessing the forest area, diseases, forest fires, afforestation and deforestation.
(2.8) Urban/Regional Planning
Satellite data, geographical information system and global positioning systems are highly useful in urban planning/regional planning. Satellite data give synoptic view of the area and help in planning the further extension of urban region and new habitation sites. Geographical information system helps in storing and retrieving the attribute data of an area and thus helps in easy solution of the problem. Global positioning system helps in mapping exact location of an object and thus helps in exact targeting of desired objects.
3.0 Education in Remote Sensing
There are good number of institutes which are giving certificate, post graduate diploma and master’s degree in remote sensing and GIS. The basic requirement of all courses should be graduate (M.Sc) in science or engineering (B.E)/technology (B.Tech) with minimum 55% marks in qualifying examinations and this condition vary from institutes to institute. The major streams of science students who can take admission in the course are geology, geophysics, geography, ecology, environmental science, marine science, forestry, botany, agriculture, physics, computer science and mathematics. The good knowledge of computer is an advantage for these courses.
The admission procedure commences in the month of April to August of the academic year. The best way is to see the websites of the choice university/institute for admission procedure and educational requirements for the particular course. The Indian Institute of Remote Sensing (IIRS), Dehradun; Birla Institute of Technology, Mesra, Ranchi, Jawaharlal Nehru Technological University, Hyderabad; Maharshi Dayanand Saraswati University, Ajmer; Institute of Remote Sensing, Anna University Chennai; Centre for Remote Sensing and Geoinformatics, Bharathidasan University Tiruchirappali, Tamilnadu; Symbiosis International University, Pune; Guru Gobind Singh Indraprastha University, Delhi; Jamia Milia Muslim University, Delhi; Aligarh Muslim University, Aligarh, Jiwaji University, Gwalior, Barkatullah University, Bhopal, Vikram University, Ujjain, Allahabad University, Allahabad are some of the good names in the education of remote sensing and GIS in the country besides many other universities which are running post graduate diploma in remote sensing and GIS. Some institutes are running short certificate courses and long term post graduate diploma courses like GIS Institute, Nodia, Institute of Geoinformatics and Computing, Gurgaon, Centre for Development of Advanced Computing (C-Dac), Nodia.
4.0 Employment Opportunities
There are good employment opportunities in the field of remote sensing and GIS. The option starts with junior research fellow to scientist. The minimum salary being starts Rs 12000/- plus HRA for JRF which extends for the post of scientist and academicians. In the government sectors the initial starting for the post of scientist starts from Scientist-SC having Rs 15600-39100 pay band with grade pat Rs 5400/- The private organisation have also good employment opportunities in this field and these are giving good salary packages depending on the experience and qualifications. Beside, application, research and teaching job opportunities, there are good scope for management field personnel’s having science or engineering background in marketing of satellite data, processing software, GIS softwares, GPS, and other technical items.
There are number of organisations which have huge scope of using satellite data and GIS in various projects like Space Applications Centre, Ahmedabad, ISRO headquarter, Bangalore, national Remote Sensing Centre, Hyderabad, Regional Remote Sensing Services Center’s at Dehradun, Kharagpur, Joghpur, Nagpur, Bangalore, North-East Space Application Centre, Shillong, State Space Applications Centres located in each state, Indian Institute of Remote Sensing Dehradun, Birla Institute of technology, Ranchi, Allahabad University, Allahabad, Punjab University, Chandigarh, Indian Institute of Technology, Roorkee, University of Pune, Guru Gobind Singh Indraprastha University, Delhi, MDS University, Ajmer and etc. The adverstiments for various posts are published in leading newspapers and Employment News. Some organisations have facility to register on-line on their web page like ISRO. In foreign counties there is good demand of remote sensing and GIS experts. There is good number of master’s doctoral and post-doctoral fellowship in foreign universities especially for developing countries candidates.
by Dr, Anup Kumar