1

Current and planned research with data collected during the IFEX/RAINEX missions

Robert Rogers

NOAA/AOML/Hurricane Research Division

2

NOAA Intensity Forecasting Experiment (IFEX)

GOALS: Through a partnership with HRD, NHC, and EMC, improve forecasts of tropical cyclone intensity by

1) developing and refining observing technologies that improve real-time monitoring of TC intensity and structure;

2) collecting observations that span the TC lifecycle in a variety of environments to initialize and evaluate the operational numerical modeling system (e.g., HWRF and next generation global models); and

3) conducting research to improve our understanding of the processes important in TC intensity and structure change (e.g., external and internal impacts on TC structure and intensity, phase changes of moisture and surface fluxes of heat, moisture, and momentum)

3

GOAL 1: New observing technology

Real-time Doppler Radar analysesAirborne Doppler radar:

• 1st transmission of real-time

quality controlled observations and

analyses to NHC from aircraft in

Hurricane Katrina (27 August,

again on 28 August).

• Can allow for the diagnosis of wind

structure and intensity in real-time

• 38 real-time analyses (including

Katrina, Ophelia, Rita, Wilma were

sent via SATCOM to NHC.

http://www.aoml.noaa.gov/hrd/project2003/doppler.html

96

Lower-fuselage radar image for Hurricane Katrina 1028 UTC 29 August

1-km altitude

96

1-km

Doppler-derived winds at 1 km

Vertical cross-section of Doppler winds

0 22 45 68 90 113 136kt

4

GOAL 1: Refined observing technology

Improved SFMR algorithm for high winds

SFMR:

• 1st season with both NOAA WP-3D

aircraft operating new commercial

SFMR transmitting surface wind

estimates back to NHC.

• Numerous storms with winds>50 m/s

enabled evaluation and modification

of operational algorithm to improve

surface wind estimation >50 m/s.

See http://www.aoml.noaa.gov/hrd/project2005/sfmr.html

Katrina

Low bias at high wind speeds reduced

70

8090

100

110

70

80

90

100

0930 UTC 29 August H*Wind analysis(including Air Force flight-level winds)

0930 UTC 29 August H*Wind analysis(including NOAA SFMR winds)

5

GOAL 2: Lifecycle measurements for

model initialization and evaluation

• Dennis (tropical storm to post- landfall) - together with NASA ER-2

(TCSP)

• Gert (tropical disturbance to landfall) - together with NASA ER-2

(TCSP)

• Katrina (tropical storm to landfall) - together with NRL P-3

(RAINEX)

• Ophelia (tropical depression to extratropical transition) - together

with NRL P-3 (RAINEX)

• Rita (tropical storm to hours before landfall) - together with NRL P-3

(RAINEX)

5 tropical cyclones flown from beginning to end of life cycle:

6

Hurricane Ivan 750 hPa streamlines and isotachs (m/s)valid 18 UTC Sept 7 2004 (from Liu et al. 2006)

First-guess field With Airborne Doppler data

GOAL 2: Lifecycle measurements for

model initialization and evaluation

Example of use of Airborne Doppler data in HWRF 3-DVar scheme

7

Example: MM5 simulations of Hurricane Dennis

1.5 km Doppler winds (m/s)

850 hPaMM5 winds (m/s)

01 UTC 7 July

0213-0300 UTC 7 July

22 UTC 5 July

2144-2224 UTC 7 July

GOAL 2: Lifecycle measurements for

model initialization and evaluation

8

GOAL 3: Intensity and structure change research

Research topics

1. Environmental influences on structure and intensity changes in Hurricane Rita

2. Along-band variations in microphysical statistics (e.g., transition of vertical motion and reflectivity statistics from convective to stratiform) as sampled by ELDORA and NOAA P-3 tail radars

3. OSEs and OSSEs using ELDORA and NOAA P-3 tail radar data to design optimal flight tracks for assimilation of Doppler radar data

9

Structural changes in Hurricane Rita

CIMSS shear 06 UTC 21 Sept

SSM/I 85 GHz 0154 UTC 21 Sept

P-3 LF image and flight tracks 19 UTC 21 Sept

GOAL 3: Intensity and structure change research

Environmental impacts on structure and intensity

changes in Hurricane Rita

10

CIMSS shear 03 UTC 22 Sept

TRMM 85 GHz 1442 UTC 22 Sept

P-3 LF image and flight tracks 20 UTC 22 Sept

Environmental impacts on structure and intensity

changes in Hurricane Rita

GOAL 3: Intensity and structure change research

11

CIMSS shear 06 UTC 23 Sept

Aqua 89 GHz 0808 UTC 23 Sept

P-3 LF image and flight tracks 2145 UTC 23 Sept

Environmental impacts on structure and intensity

changes in Hurricane Rita

GOAL 3: Intensity and structure change research

12

21 Sep

22 Sep

Wind speed (m/s) at 5 km

Wind speed (m/s) at 1 km

Ratio of 5-km to 1-km winds

Structural changes in Hurricane Rita

GOAL 3: Intensity and structure change research

13

HRD data sets

14

HRD data sets