Dr. JoAnn (Jodi) Crandall University of Maryland Baltimore County (UMBC) crandall@umbc
Jeffrey B. Halverson, UMBC Alex Martin, UMBC
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Transcript of Jeffrey B. Halverson, UMBC Alex Martin, UMBC
Multi-Scale Analysis of the Kinematic and Thermodynamic Structure of TS Humberto Using
Dropsonde and Satellite Data
Jeffrey B. Halverson, UMBCAlex Martin, UMBC
Research Objectives• Multi-scale analyses: Satellite, environmental, in situ
dropsonde structure• Study warm core, vortex symmetry, shear interactions, SAL
interactions – in context of a “dud” TC season with hostile synoptic environment (i.e. dry air, subsidence)
• Develop 3D structural visualizations utilizing a GIS framework• Hurricane Humberto (2013)• Hurricane Gabrielle (2013)• Upcoming 2014 cases• 17-year TC dropsonde climatology
Humberto Case Study• Developed on September 7th, 2013• Became TS strength on September 9th
• Reached peak intensity on September 14th at 80 knots
• Sampled by AV-6 on Sept 16-17 using racetrack pattern
• Developed deep convection in north portion
• Highly asymmetric, disjointed storm structure
Snapshot of Humberto at peak intensity
4 Hours before first drop 21 minutes after first drop
7 minutes after last drop55 minutes before last drop
IR
37 GHz 85 GHz
85 GHz
0145 UTC IR imagery
White arrow represents shear vector; black arrow is storm motion
0437 UTC 85 GHz Microwave Imagery
Wavenumber 1 Asymmetry
Mature DMC
InitiationOf DMC
SubsidenceRegion
- Strong, unidirectional deep shear interacting
with storm- Magnitude of shear vector = 23 m/s- Strong asymmetry /wrt/ vortex and deep convective region - Suggestive of a wave-number one structure
GIS ArcScene Analysis – 3D visualization
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x Deep Layer Shear 270° 23 m/s
vortex center
Storm Motion
Examine thermodynamic and kinematic structure using framework of downshear and upshear quadrants (RAOB software)
Composite Dropsonde Structure
Deep Shear
0015 UTC
0305 UTC
0408 UTC
Humberto Case Study Summary• Highly asymmetric, struggling TC• Low level vortex center exposed • Deep moist convection (DMC) displaced to north of center• Vortex wind maxima in NE quadrant /wrt/ deep shear vector• DMC triggered in NE quad, within low level speed convergence zone • Overall structure may be linked to strong wave number one
asymmetry• Shallow, weak warm core on southern edge of DMC mass (likely
subsidence induced)• Need to better understand if there is any SAL interaction• Need to develop understanding of large-scale environmental
(hostile) context for the storm’s mesoscale structure
NCAR Dropsonde Re-Analysis
• 1996 to 2012 NOAA dropsonde dataset• Build composite vertical profiles inside Atlantic basin
TC eye, eyewall, rainbands, surrounding environment• Composites as a function of radial distance, quadrant
/wrt/ motion vector, storm intensity• PBL wind structure, • 120 tropical cyclones included• 13,681 quality controlled soundings• Article by J. Wang et al. submitted to BAMS
Composite Wind Profiles By Intensity Category
Questions?