Environmental and Convective Influence on Tropical Cyclone Development versus Non-Development.
Abstract
Composite and individual case analyses were made with USAF northwestern Pacific 950 mb (approx 1500 feet) investigative reconnaissance flights into tropical disturbances. Physical processes associated with early-stage tropical cyclone development vs. non-development were studied. Analysis of a 7-year period provides about 100 cases of development vs. 100 cases of non-development. Significantly higher radial inflow is observed in the inner-core of developing cases as compared to non-developing cases. Many formation cases had strong 'packets' of radial momentum surges to inner-core radii at selective azimuthal locations. These wind surges were related to satellite-observed concentrations of deep convectuon near the inner- core of the developing disturbances and appear to be environmentally induced. Another factor influencing tropical disturbance's upper-tropospheric (250 mb) relative wind 'blowthrough' or ventilation. The direction of the 250 mb relative wind to the tropical disturbance's moving center was found to have a major influence on the location of the distrurbance's meso-scale vortex ( 1-2 deg in diameter) or Low-Level Circulation Center (LLCC) in relation to the center of the parent cloud cluster convection . A fundamental characteristic of developing disturbances over non-developing disturbances was their ability to generate more LLCCs.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1987
- Accession Number
- ADA185231
Entities
People
- Patrick A. Lunney
Organizations
- Air Force Institute of Technology