10 / 20

Which of the following choices lists only main cloud genera that indicate an unstable atmosphere?

  • A
    Cirrocumulus, altocumulus, cumulus.
  • B

    Cirrostratus, nimbostratus, stratus.

  • C

    Cirrocumulus, altostratus, altocumulus.

  • D

    Cumulonimbus, stratus, cirrocumulus.

Refer to figure.

Clouds are formed by air being lifted and cooled adiabatically => until the condensation level, where saturation is reached, and water vapour condenses and clouds form.

- The type of clouds which will be formed depends on the type of air mass:

  • STABLE (layer type of clouds will form - STRATIFORM) - great horizontal extension, little vertical development: ST, SC,AS,NS,CI,CS.
  • unstable (heap type of clouds - CUMULIFORM) - extensive vertical extension: CU,TCU,CB,AC,CC.
Note: the suffix “cumulus” is a great indication of possible instability – cumuliform.

Your Notes (not visible to others)



This question has appeared on the real examination, you can find the related countries below.