Question

Which satellite sensor is used to monitor the environmental changes like urban growth and deforestation?

• A. LiDAR sensor
• B. Radar sensor
• C. Magnetometer sensor
• D. Infrared sensors

Hint:

• Monitoring urban growth and deforestation often involves analyzing changes in land cover, land use, and vertical structure.
• LiDAR provides precise 3D measurements of the surface, excellent for mapping building heights, urban extent, forest canopy structure, and detecting forest loss or degradation.
• Optical/Infrared sensors (e.g., on Landsat, Sentinel-2) are also widely used to classify land cover, monitor vegetation health (using indices like NDVI), and detect changes over large areas.
• Radar sensors can also monitor these changes, especially in cloudy regions.
• Magnetometers are not used for this purpose.

Answer 1

The Correct Option is A

To determine which satellite sensor is used to monitor environmental changes like urban growth and deforestation, we need to consider the capabilities of each sensor type.

1. Understanding the Concepts:

- LiDAR (Light Detection and Ranging) sensor: Uses laser light to create detailed 3D models of the Earth's surface. It's useful for precise measurements of elevation, vegetation structure, and changes in land use including urban growth and deforestation.
- Radar sensor: Uses radio waves to detect objects and measure distances. It can penetrate clouds and is effective for mapping terrain and monitoring changes in land cover. While useful, LiDAR provides more detailed structural information.
- Magnetometer sensor: Measures the strength and direction of magnetic fields. Primarily used for geophysical surveys and navigation, not environmental monitoring of this type.
- Infrared sensors: Detect infrared radiation, which is related to temperature. They are useful for monitoring vegetation health and thermal properties, but less effective for direct mapping of urban growth and deforestation compared to LiDAR.

2. Evaluating the Options:

- LiDAR excels in creating high-resolution elevation models that are ideal for detecting and monitoring changes in urban areas (building heights, new construction) and forested areas (forest canopy height, deforestation extent).
- Radar can penetrate clouds, but it generally provides less detailed structural information than LiDAR.
- Magnetometers are not applicable to this type of environmental monitoring.
- Infrared sensors are more suited for vegetation health and thermal mapping.

3. Determining the Most Suitable Sensor:

Considering the need for detailed structural information for observing environmental changes like precise urban growth mapping and deforestation extent, LiDAR sensors are the most suitable.

Final Answer:

The satellite sensor used to monitor the environmental changes like urban growth and deforestation is the LiDAR sensor.