What is remote sensing?
In simple words, obtaining information about anything without being in physical contact with that object is known as remote sensing.
A typical remote sensing system comprises a platform (satellite or drone or flight), a sensor (not in direct contact with the object), and a data processing station. If we combine all these components we can acquire various characteristics of an object.
History of Remote Sensing:
Mapping is not new, the earliest civilizations around 1292 BC drew maps to mark the boundaries but after the 19th century, with the advancement of computers and a good network of satellites now we have a huge amount of comprehensive data of Earth.
I would like to draw your attention to the first ‘adhayaye’ of the epic Bhagavad Gita:
धर्मक्षेत्रे कुरुक्षेत्रे समवेता युयुत्सवः।
मामकाः पाण्डवाश्चैव किमकुर्वत सञ्जय।।1.1।।
Here the blind King Dhritarashtra is anxious and curious to know about the battle of Kurukshetra, but he is away from the battlefield and has no knowledge about the battle. So he asks his charioteer Sanjaya to give him an account of the war, Sanjaya was granted a divine vision that enabled him to oversee the entire battle and narrated the whole war.
If we compare this to the basic concept of remote sensing, the war occurring in Kurukshetra is our object under study, Sanjaya is a platform and his divine vision is a sensor and King Dhritarashtra is the data processing unit.
Remote Sensing is used in almost every field, in this section we will focus on the applications of remote sensing in the field of Environment.
Remote Sensing in Forestry and Environment:
It is no surprise that the rate of deforestation is very high in numbers and the forest cover is depleting day-by-day, this hurts the plant and animal species that eventually leads to the degradation of biodiversity, we need a robust mechanism to monitor the forest cover.
Remote Sensing and GIS is just the way to do it:
- It is very helpful in mapping and monitoring the forest cover and the forest density.
- It can help categorize the forest based on the density of the forest.
- Remote Sensing helps document the type of plant and animal species.
- The multi-date images help to analyze the current changes occurring within the forest area.
- It gives detailed plant and animal composition.
- As we all are aware of how dangerous forest fires can be so they can help create fire protection plans through continuous monitoring and mapping.
- Remote sensing data can help in ecosystem management, it can make an inventory of plants and animal habitats to understand each bio-geographical zone treated as bio-reserves.
- Remote Sensing data can be used to create a comprehensive EIA report.
Remote Sensing in Disaster Management:
Any kind of disaster leaves damage of the highest order behind, an already prepared database can help efficient management of disaster and relief.
- Database of the transport network, settlement areas, number of people residing, river system, land use pattern, etc can help plan rescue operations.
- Early warning systems can be enabled to save lives.
- The forecasting and warning could lower the risk of disaster.
- Real-time data obtained from the satellite can help assess the situation leading to an efficient disaster management plan.
Remote Sensing in Soil and Agriculture:
The population needs food, and to grow the food we need the soil of good quality hence monitoring and mapping through remote sensing becomes a task of high priority.
- Remote Sensing helps inaccurate assessment of crop production.
- Crop acreage estimation, crop condition, crop yield production, water management for irrigation is possible.
- Regional soil mapping, erosion assessment, conservation mapping, prioritization of watersheds is also possible using Remote Sensing.
Remote Sensing in Land use study:
As we know population in the urban areas is increasing many folds proper utilization and management of land is an important task that will help us achieve optimum results.
- Identification of drought-prone areas is possible.
- The details of cropping seasons like Kharif, Rabi, or Boro can be mapped.
- Wastelands can be identified and some development projects can utilize that land.
- Details regarding rivers, plantations, roads, rural settlements, urban areas, commercial centers, forests can be documented and the data can be used for policy planning and execution.
Remote Sensing in Geology and Geomorphology:
With the advancement in Remote sensing, our knowledge of Geology and Geomorphology has been refined
- The thermal infrared images are used for oil and gas field explorations.
- Synthetic Aperture Radar (SAR) systems can be used for mapping topographic relief that is very commonly used in structural geological mapping.
- Regional Tectonic Mapping is possible.
- Determination of groundwater tapping zone, mineralization zone, and major features like folds and faults can be documented.
- Different landforms can be identified using Remote Sensing.
Source and Reference:
An Introduction to Geographic Information Technology: Sujit Choudhary, Deepankar Chakrabarti, Suchandra Choudhary.