Interpretation of Satellite Imageries
The data obtained from remote sensors the purpose of extracting information regarding the forms and patterns of objects and phenomena on the Earth’s surface. With different sensors yielding photographic and digital data products, both qualitative and quantitative properties of features can be extracted using visual interpretation methods or digital image processing techniques.
Visual interpretation involves manually reading images for object identification. Conversely, digital images require hardware and software to extract desired information. Due to constraints in time, equipment, and accessories, we’ll focus solely on visual interpretation methods.
Elements of Visual Interpretation:
1. Tone or Colour: Objects reflect energy in various spectral regions, resulting in tones or colours in images. Tone or colour variations depend on surface properties and composition. For instance, healthy vegetation reflects strongly in the infrared region, appearing bright red or light-toned in standard false colour composites.
2. Texture: Texture refers to minor tone or colour variations caused by aggregated smaller features. Different objects exhibit various textures, from smooth to coarse, aiding in their identification. For example, dense residential areas appear fine-textured, while scrubbed lands display coarse texture.
3. Size: Object size, discerned from image resolution or scale, helps identify features such as industrial complexes, stadiums, and settlements.
4. Shape: The outline or form of an object provides important clues for identification. Distinctive shapes aid in identifying features like Sansad Bhawan or railway lines.
5. Shadow: Shadows cast by objects are influenced by the sun’s angle and object height. Some objects, like Qutub Minar or minarets, are identifiable based on their shadows.
6. Pattern: Repetitive spatial arrangements of features form distinct patterns, aiding in identification. Orchards, plantations, or planned residential areas exhibit recognizable patterns.
7. Association: The relationship between objects and their surroundings, along with their geographical location, provides valuable information. Educational institutions, stadiums, or industrial sites often have specific associations with their surroundings.
These elements collectively enhance the interpretation of remote sensing images, enabling a better understanding of the Earth’s surface features and phenomena.
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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.