What is the primary trigger for a visible cloud structure to dissipate or appear to sink?

Answer

The introduction of drier air, causing droplets to evaporate back into vapor

Clouds are sustained by saturation; when drier air mixes in, it causes the liquid water droplets to transition back into invisible water vapor through evaporation, leading to the cloud's dissipation.

What is the primary trigger for a visible cloud structure to dissipate or appear to sink?
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