Describe the Doppler effect's role in weather radar.

• A. It measures the radial velocity of atmospheric targets, allowing detection of wind patterns, shear, and motion in storms.
• B. It measures precipitation type via reflectivity only.
• C. It tracks aircraft altitude using Doppler shift.
• D. It computes temperature from backscatter.

Answer: (B)

The Doppler effect in weather radar is about detecting how fast targets inside the air are moving toward or away from the radar by measuring a shift in the returned signal’s frequency. This radial velocity information lets you map the wind field within storms, showing patterns like inflow, outflow, shear, and rotation. From these velocity measurements, you can spot where winds are strengthening or changing direction, which helps identify features such as gust fronts, mesocyclones, and potential tornado development.

This is different from simply looking at reflectivity, which is about how much radar energy is scattered back and relates to how much precipitation is there and its size distribution, not the motion of the air. Doppler velocity isn’t used to determine precipitation type, track aircraft altitude, or compute temperature from backscatter; those require other data and methods. The Doppler capability specifically provides the wind information that reveals storm dynamics.