Stages in Remote Sensing
Remote sensing involves several processes to gather information about the Earth’s surface. These processes help collect data on the properties of objects and phenomena. Here are the basic steps involved:
- Source of Energy: The primary source of energy used in remote sensing is the sun. Artificial sources like flashguns or radar beams are also used to collect information.
- Transmission of Energy: Energy from the source travels to the Earth’s surface as electromagnetic radiation (EMR). This radiation includes various types of waves, such as gamma, X-rays, visible light, and microwaves.
- Interaction with Earth’s Surface: The energy interacts with objects on the Earth’s surface, leading to absorption, transmission, reflection, or emission of energy. Different objects respond differently based on their composition and properties.
- Propagation through Atmosphere: Reflected or emitted energy re-enters the atmosphere, where it interacts with gases, water molecules, and dust particles. These atmospheric constituents can modify the properties of the original energy.
- Detection by Sensor: Sensors onboard satellites detect the reflected or emitted energy. These satellites orbit the Earth in near-polar sun-synchronous orbits, collecting data from a distance.
- Conversion to Digital Data: The energy received by the sensor is electronically converted into digital images, consisting of digital numbers arranged in rows and columns.
- Information Extraction: After receiving the image data, errors are eliminated, and information extraction is performed using digital image processing techniques or visual interpretation methods.
- Conversion to Map/Tabular Forms: The interpreted information is then converted into thematic maps, and quantitative measures are taken to generate tabular data.
Chapter 6: Introduction to Remote Sensing| Class 11 Geography Practical Work
Class 11 Geography Ch 6 Introduction to Remote Sensing Notes: Introduction to Remote Sensing is the sixth chapter in CBSE Class 11 Geography, which discusses the concept of Remote Sensing and its various forms. The chapter explains how this technique works, its different methods, and how it’s used in various fields like geography, agriculture, and environmental science.
Students learn about the sensors used to collect data, like cameras and scanners, and how they create images and information about the Earth. They also learn how to analyze this data to understand changes in things like land use, vegetation, and the environment. Overall, the chapter helps students understand how remote sensing helps us learn more about our planet from afar.