Rainband and Intensity Change Experiment “RAINEX”

An Observational and Modeling Study of Hurricane Rainbands and Intensity Changes

(Collaboration between NSF & NOAA, NSF ~$ 3+M)

NSF PIs: Shuyi S. Chen and Robert A. Houze, Jr.

model Doppler radardropsondes

•Use a/c Doppler radar to observe both eyewall and rainband internal vorticity structures simultaneously

•Use intensive dropsondes for thermodynamic environment of mesoscale rainbands and eyewall to support both analysis and modeling Seek match between model and aircraft- observed structures at an instant of time, in both eyewall and rainband

•Use model to determine how the vorticity features evolve and storm intensity changes

Approach:

1) Foundation for project operations plan, to be written after meeting

2) Critical operations issues:

• Flight track plan, incorporating both Doppler & dropsondes

• Communications links, including radar data

• Science operations center, for near real time synthesis of a/c data, model output, & other info

• Contingency plans, if weather doesn’t cooperate

• Other

3) Data management & archive

4) Timeline leading up to hurricane season

5) Meeting report—due next week!!

RAINEX Meeting Objectives

Four characteristic tropical cyclone rainband/eyewall structures

RAINEX A/C Plan

Suggested tracks of GIV,C130

100 km

3 a/cmissionNRL-blackPiggy-whiteKermit-blueGIV/C130-red

100 km

2 a/cmissionPiggy-whiteKermit-blueGIV/C130-red

100 km

2 a/cmissionNRL-blackKermit-blueGIV/C130-red

RSMAS

C130/GIV NRL/P3KermitPiggy

ATD

NHCJOSS

airground

Simplified RAINEX Data Flow

HRD

Lee (NRL)Smull (NOAA or NRL)

Jorgensen* (NOAA or NRL)Chen (NOAA or NRL)

Rogers (NOAA)M. Black (NOAA)Gamache (NOAA)

Dodge (NOAA)Zipser* (NOAA)

*volunteer

P3 Airborne Mission Scientists

Dropsondes from high altitude Environment Eyewall Principal rainband

Protocol for requesting dropsondes RAINEX-HRD-NHC-EMC-CARCAH

Communications & coordination—

43 needs to be lead P3 Need to transmit LF every 10 to 15 mins, content? People who will do this development Operations Dropsonde chute on NRL P3 (pressurization)

Some Issues identified yesterday

RAINEX A/C Plan

Suggested tracks of GIV,C130

1) RAINEX critically needs PV budget information need dropsondes launched from the GIV and/or C130 flying at 30,000 feet. Best if in eyewall region and principal band region. To what extent can this be done?

2) Can RAINEX desired tracks be done within the constraints of NOAA operational surveillance flights and HRD research flights?

3) Can GIV dropsonde flight tracks be reprogrammed while a/c are in the air?

4) What is the exact protocol for RAINEX to request special dropsonde flight patterns?

Specific Questions Regarding Dropsonde Flight Tracks

RAINEX TIMELINE

Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

2004 2005

Field phase

Practice Missions

Final setup & testing of Science Operations Center

Initial setup of Science Operations Center

Planning Meeting in Miami

Funding Approval

Initial information gathering trip to HRD and RSMAS

Science Objectives

Use a/c to examine the dynamic and thermodynamic structures of hurricane outer rainband regions where the positive potential vorticity associated with deep convective cores are located

Use model to investigate the interactions of the rainbands and primary hurricane vortex circulation and their role in hurricane intensity change.

In the convective rainband region outside of the hurricane inner core, convectively induced potential vorticity may be “axisymmetrized” by high wave number Rossby waves.

Working hypothesis, based on recent research:

1) How do PV maxima associated with rainbands organize (axisymmetrize) into the primary eyewall?

2) How do PV maxima associated with rainbands outside the primary eyewall interact with the eyewall?

3) How do PV maxima associated with rainbands outside the primary eyewall axisymmetrize into a secondary eyewall

4) How do the secondary and primary eyewall interact with each other

Specific questions