Boundary-Layer Meteorology

, Volume 28, Issue 1–2, pp 23–49 | Cite as

Downdrafts from tropical oceanic cumuli

  • R. P. Addis
  • M. Garstang
  • G. D. Emmitt
Article
Accepted:

Abstract

Simultaneous observations at up to six levels through a depth of 1100 m from a tethered balloon and instrumented ship's boom of 49 gust fronts associated with convective clouds are used to describe the mean and the detailed characteristics of tropical oceanic cumuli outflow at the surface and in the boundary layer.

The changes in temperature and velocity of the maritime tropical gust front are about 50%; of the changes observed in mid-latitude convective outflows. Vertical velocities at the gust front ⩾l m s-1 are continuous through the lower 500 m for time periods up to 8 min implying vertical displacements of at least 500 m entirely sufficient at the observed humidities (q >- 15 g kg-1) to initiate new cloud growth. Horizontal and vertical vorticity in the order of 10-3 s-1 to 10-2 s-1 is observed at the gust front.

Keywords

Boundary Layer Vorticity Vertical Velocity Vertical Displacement Detailed Characteristic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© D. Reidel Publishing Company 1984

Authors and Affiliations

  • R. P. Addis
    • 1
    • 2
  • M. Garstang
    • 1
  • G. D. Emmitt
    • 1
    • 3
  1. 1.Department of Environmental SciencesUniversity of VirginiaCharlottesvilleUSA
  2. 2.JIMAR, University of HawaiiHonoluluUSA
  3. 3.Simpson Weather AssociatesCharlottesvilleUSA

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