Which weather condition is most associated with drift and reduced deposition?

• A. Heavy rain and wind gusts.
• B. High humidity and strong updrafts.
• C. Calm winds with high temperatures.
• D. Inversions can cause drift and reduce deposition.

Answer: (D)

Temperature inversions create a stable air layer near the ground that suppresses vertical mixing. When this happens, pesticide droplets remain trapped in that layer and are carried horizontally by the wind, leading to more off-target movement (drift) and less of the spray depositing on the intended surface. This combination—little vertical air movement but continued horizontal transport—explains why inversions are most associated with drift and reduced deposition.