Why do clouds have well-defined boundaries?

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12 points·spython··3 comments

The explanations are very technical on his clouds work and maybe that's what the asker of the question wanted. Really the question seems to beg a simple answer.

Clouds don't have a well defined boundaries. They are very large and we are generally very far away. If you fly through clouds or walk/drive through them on a mountain top it's clear they're not defined at all. From far away it looks like that cloud is a ceiling and when you reach it there's a binary effect but it's not.

Same thing from viewing lakes or oceans from very high up. They can look like big static bodies.

No qualms about your point, but to approach closer to the asymptote of this argument no "object" has really a well-defined boundary one you look at it close enough (spatial scale and/or time-resolution scale).

Going back to J.C. Maxwell's complaints that many physicists of his time did not understand that we do not perceive matter directly, only forces. Of cause, this should be nowadays high-school level attentive student's knowledge.

Perhaps useful distinction, depending on the level of analysis, one can split into categories: a "mathematical/physics" object versus the "reality". E.g. in thermodynamics, (mathematical) cloud has a clear and precisely defined boundary.

Anders Sandberg> the scattering intensity increases with the sixth power of the diameter

That is convincing to me.

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