THE SUBTROPICAL CYCLONE
Abstract
Upper level cut-off cyclones, first identified in middle latitudes, are found as well in lower latitudes where they often extend to the surface and persist for long periods. On 4 April 1960, TIROS I photographed a portion of a near steadystate subtropical cyclone over the eastern Pacific. Composited surface and upper air observations of the cyclone, when combined with the photographs, presented a sketchy but consistent picture of the circulation. A subtropical cyclone which developed near Lihue in February 1951 provided additional details, particularly of the important stability and weather changes accompanying cut-off. The two cases form the foundation for a subtropical cyclone model. Development occurs as in middle latitudes. The mature cyclone, which approximates horizontal symmetry, comprises a direct subsiding circulation in the lower troposphere, separated by a subsidence inversion from a trade wind-like regime in the surface layers. Because of its energy exporting character and the insignificant effect of surface friction, a subtropical cyclone apparently does not decay, being usually absorbed by a large amplitude trough in the polar westerlies. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1961
- Accession Number
- AD0258558
Entities
People
- C.s. Ramage