Which of the following is an example of an indirect weather observation system?

Radar is considered an indirect weather observation system because it relies on emitted radio waves to gather information about weather conditions. Rather than measuring atmospheric phenomena directly, radar monitors the return signals from these waves to assess precipitation intensity, wind patterns, and storm systems. This method allows meteorologists to analyze weather events over a large area without the need for direct contact with weather elements.

In contrast, weather buoys, thermometers, and anemometers provide direct measurements of environmental conditions. Weather buoys measure both oceanic conditions and meteorological data directly from the water's surface; thermometers directly quantify air temperature; and anemometers measure wind speed by capturing the movement of the air. These systems collect specific data points that directly correspond to observable weather characteristics, distinguishing them from radar's indirect observational nature.