Types of image

1. Visible Image:

- A visible image is captured in the range of the electromagnetic spectrum that is visible to the human eye, typically spanning wavelengths from about 400 to 700 nanometers (nm). These images resemble what the human eye sees and are often used for visual inspection and interpretation.

2. Infrared Image:

- Infrared imagery captures radiation in the infrared portion of the electromagnetic spectrum, beyond what is visible to the human eye. It is useful for applications such as night vision, heat detection, and identifying temperature variations.

3. Multispectral Image:

- Multispectral imagery is captured in multiple distinct bands or channels across the electromagnetic spectrum. Each band provides information about a specific range of wavelengths, allowing for the analysis of different characteristics of the scene, such as vegetation health or land use.

4. Hyperspectral Image:

- Hyperspectral imagery captures data in numerous narrow and contiguous bands across the electromagnetic spectrum, often with hundreds of spectral bands. This high spectral resolution allows for detailed analysis of materials and their properties in a scene, making it valuable in fields like geology and agriculture.

5. LIDAR Image:

- LIDAR (Light Detection and Ranging) imaging uses laser pulses to measure the distance to objects or surfaces. It creates highly accurate three-dimensional maps of terrain, structures, or objects by measuring the time it takes for the laser pulses to return.

6. RADAR Image:

- RADAR (Radio Detection and Ranging) imaging uses radio waves to detect and locate objects or terrain. RADAR images are particularly useful in applications like weather forecasting, aircraft navigation, and military surveillance.

7. Thermal Imagery:

- Thermal imagery captures the infrared radiation emitted by objects based on their temperature. It is used to visualize variations in temperature, making it valuable in applications such as building inspections, search and rescue operations, and monitoring industrial equipment for overheating.

Each type of imagery has its own unique characteristics and applications, making them essential tools in various fields, including remote sensing, environmental monitoring, geology, agriculture, and more.

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Accuracy Assessment

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Change Detection

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Geographic phenomena fields objects boundaries.

In geography, geographic phenomena refer to features or processes that can be observed and studied on Earth's surface. These phenomena can be classified into three main categories: fields , objects , and boundaries . Each category has distinct characteristics, representations, and applications in Geographic Information Systems (GIS). 1. Fields A field represents continuous, spatially varying data where a value is present at every location within the study area. It describes conditions that exist across a geographic area. Characteristics : Continuity : Fields have no discrete boundaries; the data is continuous. Gradual Variability : The values of a field change gradually across space. Representation : Typically modeled using raster data in GIS, where a grid structure assigns a value (e.g., temperature or elevation) to each cell. Examples : Temperature Map : Shows temperature variation across a region. Rainfall Distribution : Displays rainfall levels over a large g...

Development and scope of Environmental Geography and Recent concepts in environmental Geography

Environmental Geography studies the relationship between humans and nature in a spatial (place-based) way. It combines Physical Geography (natural processes) and Human Geography (human activities). A. Early Stage 🔹 Environmental Determinism Concept: Nature controls human life. Meaning: Climate, landforms, and soil decide how people live. Example: People in deserts (like Sahara Desert) live differently from people in fertile river valleys. 🔹 Possibilism Concept: Humans can modify nature. Meaning: Environment gives options, but humans make choices. Example: In dry areas like Rajasthan, people use irrigation to grow crops. 👉 In this stage, geography was mostly descriptive (explaining what exists). B. Evolution Stage (Mid-20th Century) Environmental problems increased due to: Industrialization Urbanization Deforestation Pollution Geographers started studying: Environmental degradation Resource management Human impact on ecosystems The field became analytical and problem-solving...

Landsat 8 Band designation and Band Combination.

Landsat 8 Band designation and Band Combination. Landsat 8-9 Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) Bands Wavelength (micrometers) Resolution (meters) Band 1 - Coastal aerosol 0.43-0.45 30 Band 2 - Blue 0.45-0.51 30 Band 3 - Green 0.53-0.59 30 Band 4 - Red 0.64-0.67 30 Band 5 - Near Infrared (NIR) 0.85-0.88 30 Band 6 - SWIR 1 1.57-1.65 30 Band 7 - SWIR 2 2.11-2.29 30 Band 8 - Panchromatic 0.50-0.68 15 Band 9 - Cirrus 1.36-1.38 30 Band 10 - Thermal Infrared (TIRS) 1 10.6-11.19 100 Band 11 - Thermal Infrared (TIRS) 2 11.50-12.51 100 Vineesh V Assistant Professor of Geography, Directorate of Education, Government of Kerala. https://www.facebook.com/Applied.Geography http://geogisgeo.blogspot.com

Vineesh V, Geography

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