Comparison of Developing versus Non-Developing Tropical Disturbances.
Abstract
Developing and non-developing western North Pacific tropical disturbances are investigated and compared utilizing Defense Meteorological Satellite Program (DMSP) and rawinsonde data. Quantitative measurements of deep convection and cirrus amounts from the satellite visual and infrared data indicates that no large deep-convective difference exists between these two classes of disturbances. Genesis appears to be related to the special positioning of the deep convection and surrounding wind fields. When genesis occurs, the deep convection appears to act indirectly to warm the tropical disturbance by means of dynamically forced subsidence. Documentation is provided to support this hypothesis. Relative vorticity, vertical shear, and characteristics of the cirrus level outflow patterns were determined to be parameters which displayed the largest difference between the two classes of developing and non-developing disturbances. It is hypothesized that the potential for tropical disturbance genesis is primarily related to: the large-scale surrounding relative vorticity at lower and upper tropospheric levels, the strength of the disturbance's dynamically forced subsidence, and magnitude of disturbance ventilation or wind blow-through.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1977
- Accession Number
- ADA047780
Entities
People
- Steven L. Erickson
Organizations
- Air Force Institute of Technology