system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a fundamental difference between tornadoes and dust devils, or is it *just* a matter of size?

Are they formed by similar (yet differently scaled) causes, or are they, at their root, different beasts that merely *resemble* each other?
Does there exist a smooth spectrum (continuum) of possible sizes, or is there a clear jump from dust devils to tornadoes, with nothing in between?
gpt
Tornadoes begin a rapid rotation of extremely powerful super cells.  The rapid rotation concentrates and accelerates, and wind shear causes it to descend to ground level.  Dust devils are small low pressure vortices caused by rising thermals and the backfill of air along the ground.  Fairly benign, but in theory could be the initial vertical development in an unstable atmosphere which leads to super cells.