Morning Glory cloud

[alexy31]

Bonjour,

Je travaille actuellement sur un nuage particulièrement typique du Nord de l'Australie. Celui-ci est permis grâce à la configuration géographique du lieu.

Voici l'explication de la formation du phénomène en anglais :

• To the west from the Gulf of Carpentaria is located the wedge-shaped Cape York Peninsula.

• Sea breezes are blowing in both sides of peninsula - it is large enough to form two independent breezes, one on each side.

• Both sea breezes clash above the middle of the peninsula and rise up.

• This clash and upward movement destabilizes the air masses - condensation of moisture takes place and there forms a cloud, which resembles a spine above the Cape York Peninsula - North Australian Squall Line.

• During the night the air cools down and descends above the peninsula.

• Meanwhile in the night the air masses over the Gulf of Carpentaria are inversed - at the water level air is cooler and higher up the air is warmer. (To meteorologists this is inversed layer - because normally warm air is below and cool air - above it.)

• Cooled air from Cape York Peninsula together with all North Australian Squall Line descends to the Gulf of Carpentaria.

• As this cooled air meets the inversed layer above the Gulf of Carpentaria, it dives below it.

• As the layer from peninsula is moving under the air masses above the Gulf of Carpentaria, there form series of waves which somewhat resemble ripples in the lake.

• This movement destabilises moist air masses and clouds form at the contact of air masses.

• Clouds form exactly in the ripples. As the air masses move, these clouds are rolled between them, like childs are rolling plasticine "sausages" with their hands.

Si j'ai bien compris la première partie, je ne comprends pas comment une zone d'inversion thermique peut se former la nuit dans le Golfe?

Merci