Question

Discuss briefly the process of remote sensing in the infrared region of the electromagnetic spectrum.

Answer 1

In the infrared region of the electromagnetic spectrum, remote sensing involves detecting energy either reflected or emitted by objects on the Earth’s surface.

• In the near-infrared (NIR) region (0.7–1.3 μm), sensors capture reflected solar radiation. Healthy green plants reflect large amounts of NIR, making it useful for studying vegetation, forests, and crop health.
• In the thermal infrared (TIR) region (3–14 μm), sensors measure emitted heat energy, also known as thermal radiation. This enables the mapping of surface temperatures, detecting urban heat islands, volcanic activity, and even underground water sources.

Infrared remote sensing is effective during both day and night and is often used in environmental monitoring, agriculture, and disaster assessment.