1
Microwave Imager TC Applications
Naval Research Laboratory, Monterey, CA2Jet Propulsion Laboratory, Pasadena, CA
3Science Applications Inc. International, Monterey, CA
Jeff Hawkins, Kim Richardson, Mindy Surratt, Tom Lee, Rich Bankert, Joe Turk2, Charles Sampson, Jeremy
Solbrig, Arunas Kuciauskas, John Kent3,
International Workshop on Satellite Analysis of Tropical Cyclones (IWSATC)
Honolulu, HIApril 15, 2010
2
Exposed LLCC
Sheared Convection
Apparent LLCC
True LLCC
3
Good central mass
Remove doubt
Large rain-free eye
Rainband structure
4
Automated Tropical Cyclone Forecasting (ATCF) System warning graphic
Latest 1-km Visible/IR imagery
(GEO/LEO)
30 minute MTSAT refresh with
AVHRR/OLS as available
Vis/IR imagery
suite
Scatterometer & CloudSat
Storm Basins
& Names
Microwave imager/sounder product suite
http://www.nrlmry.navy.mil/TC.html
FNMOC: https://www.fnmoc.navy.mil/tcweb/cgi-bin/tc_home.cgi
5
Microwave Imager Temporal Changes
512
km
Katrina
6
14 d
eg
Tropical Cyclone Yasi
Microwave Imager Temporal Changes
7
Concentric Mode 1: Evolve into one larger diameter eye
512
KM
Microwave Imager Temporal Changes
8
Satellite – Aircraft Comparisons
North
NW
TMI 85H 9-22-05 1443Z
NOAA 43 1430-1520Z 10,000’
TMI Tb
Flt level wind
9Courtesy: Tom Lee
COMET Module – TC Microwave
http://meted.ucar.edu/npoess/ocean_winds/index.htm
TC specific focus with microwave sensors
10
Microwave Imager Training
http://www.nrlmry.navy.mil/training-bin/training.cgi
11
Automating TC Intensity???
Huge-Intense Shear - Weak Annular - Intense
Small-IntenseWrapping? Wrapping
12
Microwave Imager TC Intensity Estimation
Machine LearningApplication
Leave-One(TC)-Out Cross Validation
Training and Testing
Atlantic Basin Data Set**319 samples from 60 TC’s**
RMSE: 13.1 kts
Segmented 85 GHz
Image feature extraction
Feature selection to reduce redundant and
irrelevant features
GOES Visible SSM/I 85 GHz
Microwave imager data provides structural characteristics not
always found in typical Vis/IR imagery.
Courtesy: Rich Bankert
13
Microwave Imager Top Impact “Features”
6. Area coverage of pixels with less than 228 K Tb
7. Number of 1-km rings (within 1-deg radius) with at least 33% pixels with < 253 K Tb
8. Average % encirclement of the 1-km wide rings within 1-2-degree radius (pixels < 253 K)
9. Maximum summation of pixel Tb values along a 1-km ring for pixels with < 228K Tb
10. Number of 1-km rings (within 1-deg radius) with at least 50% pixels with Tb < 253 K
1. Symmetry measure – based on the 2-deg radius gradient vector angles relation to center
2. Average % encirclement of 1-km wide rings within 1-deg radius area (pixels < 253 K)
3. Difference in Tb of warmest center pixel and coldest surrounding pixel
4. Summation of pixel Tb in the SE quadrant of the “eye” region
5. Average of the maximum Tb on each ring in the 1-degree radius area
14
IR Image GradientGradient DetailDetail
ArtificialArtificial Vortex Vortex GradientGradient DetailDetail
Ritchie: Gradient Vector Feature
15TIMELINE
RMSE (kts)
12.0
15.0
14.0
13.0
20.0
21.0
19.0
18.0
17.0
16.0
• Cubist (machine learning tool) Cross Validation (CCV) - all original features
• Manual estimation (Jeff)
• CCV - new feature set (modified original, new features added)
• CCV - feature selection (remove redundant and irrelevant features)
• CCV - new features added to total set, re-do feature selection
• CCV - 277 samples - high shear samples removed, re-do feature selection (Jeff RMSE – 16.7 kts)
• CCV - 319 samples – add gradient vector (Ritchie) feature
Automated Microwave Imager TC Intensity Estimates319 Atlantic basin samples [1995-2005]Features computed from SSM/I 85 GHz channel data
• Manual estimation (Jeff)
TC Intensity – Microwave Imager
16
Problematic TC Structure Cases
High Shear Center Convection Dying Inner Eye
SSM/I 85 GHz images (BT)
17
TC intensity – Microwave Imager (2006-2009 Data Sets)
Adding Near Real-Time Data Sets from NRL-TC Web Page Includes AMSR-E, TMI, SSMIS in addition to original SSM/I
18
TC intensity – Microwave Imager (Adding 37 GHz Data)
85 GHz H-pol37 GHz H-pol
Tropical Cyclone Yasi (11P)
85 GHz H-pol37 GHz H-pol
Typhoon Sinlaku (15W)
19
F-15 SSM/I 0723Z Aqua AMSR-E 0332Z
85 GHz H-pol 89 GHz H-pol
F-17 SSMIS 0750Z
91 GHz H-pol
Colder Tb at higher frequencies imply stronger storm: Incorrect
Microwave Channel Intercalibration
20
Hurricane Bonnie TB Simulations
Passive Microwave Channel Intercalibration Process
TMI 85 GHz H
AMSR-E 89 GHz H
TMI 85 GHz H - AMSR-E 89 GHz H
8-10 K Differences In Deep Convection
Huge potential to create issues:
- Qualitative assessments
- Quantitative analyses (intensity alg)
21
SSM/I
TRMM
TMI
AMSR-E
AMSR
WINDSAT
SSMIS
FY-3
MWRI
Russia MTVZA
YEAR 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20
Primary mission Extended mission March 2011
Hawkins
Passive Microwave Imager Missions
Launches Future
Megha
Tropiques MADRAS
GCOM AMSR
GPM
DWSS-1
Satellite sensors soon to cease functioning
Top Related