The meaning is:

Some of these expressions are detailed here because they describe wind related phenomena.

TLFi

Car: Conj. de coordination introduisant une prop. qui explique ou justifie ce qui vient d’être énoncé.

Décrivant is related to expressions populaires that way:

Quelques expressions populaires décrivant des phénomènes de vent ou sont comportement sont détaillées ici.

You might be confused by the fact the sentence starts by telling the wind inspired many expressions so the causality can be considered to be redundant. What was indended is to confirm or insist about the reason why they are listed there. The sentence might have read:

…dont quelques unes sont détaillées ici justement parce qu’elles décrivent des phénomènes de vents… (precisely because they describe…)

If what bothers you is the participe présent, the sentence is close to this one where the gerund is used in English:

some of them detailed here for describing wind-related phenomena…

This syntax is not used in spoken French. Here is a similar usage:

A qui s’adressent les Indemnités Journalières (IJ) ?
…
Aux professionnels de santé libéraux dont le confinement à domicile est recommandé car présentant certaines fragilités de santé les exposant à des formes graves du Covid-19

It is exactly equivalent to

…recommandé parce qu’ils (les personnels de santé concernés) présentent certaines fragilités…

The meaning of "car" is the usual one (because) and I believe it is an unhappy choice of the writer, who was perhaps at a loss for a proper term and in a hurry. Since the beginning of the sentence says that there exist many such expressions and that some have been chosen, the connecting word (car) says that the choice of expression relating to the wind has been made because they relate to the wind (roughly). Of course, that is not the right idea, the right connection being one of particularization. The following sentence is a possibility that makes sense of this sentence.

• Le vent a suscité beaucoup d’expressions populaires dont sont détaillées ici quelques unes qui décrivent des phénomènes de vents ou qui s’inspirent de son comportement.