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Title: Abrupt cloud clearing of marine stratocumulus in the subtropical southeast Atlantic
We document rapid and abrupt clearings of large portions of the subtropical marine low cloud deck that have implications for the global radiation balance and climate sensitivity. Over the southeast Atlantic, large areas of stratocumulus are quickly eroded, yielding partial or complete clearing along sharp transitions hundreds to thousands of kilometers in length that move westward at 8 to 12 meters per second and travel as far as 1000+ kilometers from the African coast. The westward-moving cloudiness reductions have an annual peak in occurrence in the period from April through June. The cloud erosion boundaries reduce cloud at ≈10-kilometer scale in less than 15 minutes, move approximately perpendicular to the mean flow, and are often accompanied by small-scale wave features. Observations suggest that the cloud erosion is caused by atmospheric gravity waves.  more » « less
Award ID(s):
1656314 1656237
PAR ID:
10098371
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Science
Volume:
361
Issue:
6403
ISSN:
0036-8075
Page Range / eLocation ID:
697 to 701
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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