Description:

✅ Visibility meter or visibility sensor

How Visibility is Measured:

Instruments Used:

Transmissometers: Measure how much light is scattered or absorbed over a set distance (e.g., at airports).

Forward Scatter Sensors: Detect light scattered by particles (fog, smoke, etc.) to estimate visibility.

Units:

Reported in meters (m) or statute miles (mi).

Example: "Visibility reduced to 500m in dense fog."

Why Not the Others?

Barometer: Measures air pressure (used for weather forecasting, not visibility).

Hygrometer: Measures humidity (water vapor content in air).

Fun Fact: Human observers (e.g., at weather stations) also estimate visibility by noting landmarks at known distances! 🌫️👀