Identification

Title

Dynamics of the transition from spiral rainbands to a secondary eyewall in Hurricane Earl (2010)

Abstract

Airborne Doppler radar captured the inner core of Hurricane Earl during the early stages of secondary eyewall formation (SEF), providing needed insight into the SEF dynamics. An organized rainband complex outside of the primary eyewall transitioned into an axisymmetric secondary eyewall containing a low-level tangential wind maximum. During this transition, the downshear-left quadrant of the storm exhibited several notable features. A mesoscale descending inflow (MDI) jet persistently occurred across broad stretches of stratiform precipitation in a pattern similar to previous studies. This negatively buoyant jet traveled radially inward and descended into the boundary layer. Farther inward, enhanced low-level inflow and intense updrafts appeared. The updraft adjacent to the MDI was likely triggered by a region of convergence and upward acceleration (induced by the negatively buoyant MDI) entering the high-(e) boundary layer. This updraft and the MDI in the downshear-left quadrant accelerated the tangential winds in a radial range where the axisymmetric wind maximum of the secondary eyewall soon developed. This same quadrant eventually exhibited the strongest overturning circulation and wind maximum of the forming secondary eyewall. Given these features occurring in succession in the downshear-left quadrant, we hypothesize that the MDI plays a significant dynamical role in SEF. The MDI within a mature rainband complex persistently perturbs the boundary layer, which locally forces enhanced convection and tangential winds. These perturbations provide steady low-level forcing that projects strongly onto the axisymmetric field, and forges the way for secondary eyewall development via one of several SEF theories that invoke axisymmetric dynamical processes.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d71n840p

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2018-09-01T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact