All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 40 9 0
PDF Downloads 9 3 1

EFFECT OF SURFACE FRICTION ON THE STRUCTURE OF BAROTROPICALLY UNSTABLE TROPICAL DISTURBANCES

R. T. WILLIAMSNaval Postgraduate School, Monterey, Calif.

Search for other papers by R. T. WILLIAMS in
Current site
Google Scholar
PubMed
Close
,
T. K. SCHMINKEUniversity of Utah, Salt Lake City, Utah

Search for other papers by T. K. SCHMINKE in
Current site
Google Scholar
PubMed
Close
, and
R. L. NEWMANNaval Postgraduate School, Monterey, Calif.

Search for other papers by R. L. NEWMAN in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

The structure of barotropically unstable disturbances in the Tropics is studied with a two-level quasi-geostrophic model. An Ekman layer is attached to the lower boundary. The equations are linearized and the most unstable mode is found numerically by using the initial value technique. Computations are made for a shear-zone wind profile and a jet profile; these fields are independent of height. The disturbance structure is found to be critically dependent on the absolute vorticity gradient in the mean flow. The predicted disturbance structures contain a number of features that are observed in tropical wave disturbances.

Present affiliation: Air Force Global Weather Central, Offutt Air Force Base, Nebr.

Present affiliation: U.S. Navy Fleet Weather Facility, London, England.

Abstract

The structure of barotropically unstable disturbances in the Tropics is studied with a two-level quasi-geostrophic model. An Ekman layer is attached to the lower boundary. The equations are linearized and the most unstable mode is found numerically by using the initial value technique. Computations are made for a shear-zone wind profile and a jet profile; these fields are independent of height. The disturbance structure is found to be critically dependent on the absolute vorticity gradient in the mean flow. The predicted disturbance structures contain a number of features that are observed in tropical wave disturbances.

Present affiliation: Air Force Global Weather Central, Offutt Air Force Base, Nebr.

Present affiliation: U.S. Navy Fleet Weather Facility, London, England.

Save