Which of the following contributes to wind pollution during pesticide application?

High wind speeds significantly contribute to wind pollution during pesticide application. When applying pesticides, if wind speeds are elevated, the aerosolized particles can easily become displaced from their intended target area. This results in drift, where pesticides travel away from the application site, potentially contaminating nearby fields, water bodies, and even urban areas. The increased kinetic energy in high winds allows for finer droplets to be carried over longer distances, exacerbating the unintended spread of chemicals.

The other factors listed do not promote wind pollution in the same way. For instance, using a low-pressure sprayer generally reduces the likelihood of drift by creating larger droplets that are less susceptible to being carried away by the wind. Low humidity levels can actually increase evaporation and may lead to some loss of pesticide effectiveness, but it does not directly influence wind pollution in the same way as high wind speeds. Optimal temperature, while affecting pesticide efficacy and application characteristics, does not contribute to the physical movement of pesticides through the air. Thus, high wind speeds are the critical factor that increases the risk of wind pollution during pesticide application.