成層圏(せいそうけん)

成層圏(せいそうけん) is the stratosphere, the second layer of Earth's atmosphere. Word formation: 成層(せいそう) (stratified layers) + 圏(けん) (sphere/zone).

ATMOSPHERIC LAYERS (low to high):

• 対流圏(たいりゅうけん): troposphere (weather occurs here)
• 成層圏(せいそうけん): stratosphere (10-50 km altitude)
• 中間圏(ちゅうかんけん): mesosphere
• 熱圏(ねつけん): thermosphere

KEY FACTS:

• Contains the オゾン層(そう) (ozone layer)
• Temperature increases with altitude (unlike the troposphere)
• Very little weather activity — skies are calm

COMMON COLLOCATIONS:

• 成層圏(せいそうけん)の気温(きおん): stratospheric temperature
• 成層圏(せいそうけん)オゾン: stratospheric ozone

NOTE:
Commercial aircraft typically fly at the boundary between 対流圏(たいりゅうけん) and 成層圏(せいそうけん).