Exploring the Effects of Wind Turbine Interference on NEXRAD Radar Data

With the advent of cleaner energy sources in recent years, there has been a marked increase in the number of wind farms all over the Unites States. While they offer many benefits, wind farms in certain locations have been found to interfere with data collection by the Next Generation Weather Radar System (NEXRAD). Specifically, wind turbines mounted on towers may be tall enough to penetrate the beam of nearby radars, yielding spurious “hot spots” of persistently high reflectivity, especially during conditions of super-refraction. This, in turn, may contaminate quantitative precipitation estimates. Furthermore, movement of the blades can bias Doppler velocity estimates and contaminate measurements of spectrum width. These effects have been observed as far as 40 km from the radar. This study examines NEXRAD data signatures of wind turbines in reflectivity, Doppler velocity, and spectrum width, and addresses possible methods incorporating dual polarization to screen for and prevent contamination of radial velocity and precipitation estimation data.