What is remote sensing used for in environmental pollution monitoring?

• A. Direct in-situ water sampling.
• B. Use of satellite or aircraft sensors to observe Earth's surface and atmosphere; track pollution plumes, land-use changes, algal blooms, and heat islands.
• C. Laboratory chemical analysis.
• D. Only weather forecasting.

Answer: (B)

Remote sensing uses sensors on satellites or aircraft to observe Earth from a distance, allowing broad, repeated views of large areas. In environmental pollution monitoring, this means you can detect and monitor pollution plumes, land-use changes that affect pollution sources, algal blooms in water, and urban heat islands over wide regions and over time. Ground-based methods like direct in-situ water sampling or laboratory chemical analysis provide precise measurements at specific sites but don’t efficiently cover large areas. While remote sensing can contribute to weather-related observations, its main value for pollution monitoring is capturing spatial patterns and temporal trends across landscapes.