Three-dimensional Structure of Intense Atlantic Hurricanes as seen by the TRMM PR. Summary and Future Work. Eyewall—All Overpasses. Introduction. Schematic of typical rain pattern as seen by radar, according to Willoughby (1988). Outer eyewall. eye. Inner eyewall. Principle band.
Three-dimensional Structure of Intense Atlantic Hurricanes as seen by the TRMM PR
Summary and Future Work
Schematic of typical rain pattern as seen by radar, according to Willoughby (1988)
Changes in Structure with Storm Intensity
TRMM and PMM Grant NAG5-13654 and NNX07AD59G
NASA ESS Grant NNX06AF17H
RAINEX National Science Foundation Grant ATM-0432623
Deanna Hence, Robert Houze and Stacy BrodzikUniversity of Washington
CFAD analysis illustrates the differences in precipitation structure as a function of radius and quadrant in intense Atlantic hurricanes. The precipitation in the eyewall annulus was mostly uniform and intense, with evidence of occasional deep convective towers. The eyewall overall tends to be stronger on the right side, likely a response to stronger convergence, but is even more so in stronger (Category 4-5) storms.
The precipitation was more shallow and stratiform in the middle radii (inner rainband region) and slightly deeper and more convective at the farthest radii (outer rainband region). In stronger storms, the rainbands are weakest and least present in the left-front quadrant, preferring the right side of the storm. In weaker storms, the left-rear quadrant is weakest, with the rainbands preferring the front of the storm.
For future work, the study will be expanded to all tropical cyclone basins for all years of TRMM mission (1998-present) to study variability in structure associated with changes in storm intensity, location, and environment including shear and SST.
The rain pattern of a tropical cyclone consists of eyewalls and rainbands arranged in patterns like that shown below. Interactions of eyewalls and rainbands may affect storm intensity changes, but relatively little information exists on the statistics of how the vertical structure of these features change with storm evolution. To better document these structures, we compile statistics of the TRMM PR data as a function of distance from storm center and quadrant..
Annulus 1 by Quadrant
Annulus 1 by Quadrant
TRMM PR Reflectivity at 03:36 on 28 August 2005
Overpasses when Category 1-2
Overpasses when Category 4-5
PMM Science Team Meeting, Ft. Collins, CO, 5 August 2008