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ADT – Advanced Dvorak Technique

ADT – Advanced Dvorak Technique. Tim Olander and Chris Velden University of Wisconsin – Madison Cooperative Institute for Meteorological Satellite Studies (CIMSS). International Workshop on Satellite Analysis of Tropical Cyclones Honolulu, Hawaii 13 – 16 April, 2011.

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ADT – Advanced Dvorak Technique

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  1. ADT – Advanced Dvorak Technique Tim Olander and Chris Velden University of Wisconsin – Madison Cooperative Institute for Meteorological Satellite Studies (CIMSS) International Workshop on Satellite Analysis of Tropical Cyclones Honolulu, Hawaii 13 – 16 April, 2011

  2. Advanced Dvorak TechniqueAcknowledgements We wish to acknowledge the inputs from those whom have provided valuable feedback regarding the ADT over the years, specifically Mike Turk and Greg Gallina at NESDIS/SAB, Andrew Burton at the Australian Bureau of Meteorology, numerous forecasters and specialists at the NOAA/National Hurricane Center and the Joint Typhoon Warning Center, past and present (too many to name here). Special thanks to Jeff Hawkins and the Naval Research Laboratory and Office of Naval Research for the support towards the development and continued advancement of the ADT!

  3. Advanced Dvorak TechniquePresentation Overview • Brief Historical Overview • Latest Advancements • Validation • Current Status and Availability • Looking Towards the Future

  4. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Validation • Current Status and Availability • Looking Towards the Future

  5. Advanced Dvorak TechniqueADT History: The ODT Step One: Creating the initial Objective Dvorak Technique (ODT)

  6. Advanced Dvorak Technique ADT History: The ODT Why develop an objective Dvorak Technique (DvT)? • Reduce subjectivity • Analyst subjectivity can be introduced in assessing scene type, applying certain DvT parameters and rules, and determining TC storm center locations • Promote uniformity • --Given the above, significant variation in DvT estimates • can sometimes exist between Operational Forecast • Centers (OFCs), as documented by IBTrACS • -- Provide objectively-based estimates as a guidance tool • Original Goal • Obtain an accuracy on par with the DvT

  7. landfall Advanced Dvorak Technique ADT History: The ODT Examples of wide intensity estimate variations between Operational Forecast Centers Regions of Note

  8. Advanced Dvorak Technique ADT History: The ODT • Retain DvT “roots”, but amend a little • Implement as much of original DvT technique as possible • Keep familiarity for analysts/forecasters (e.g. EIR branch) • Output that includes T# and CI# values • Utilize same scene type classifications • Integrate DvT steps/rules (e.g. DvT Rule 9 for weakening) • Implement a time averaging scheme • Operate the ODT at hourly (or even 30-min.) increments • Utilize a “history file” to store critical information for each analysis • Employ 6-h (now 3-h) running average of T# estimates to smooth minor fluctuations from estimate to estimate, apply to final CI# • Implement additional features requested by users • Add user position or scene override functionality • ODT applications limited to TCs > T3.5 (strong tropical storms and higher)

  9. Advanced Dvorak TechniqueADT History: The ODT Development of an objective scheme to estimate tropical cyclone intensity from digital geostationary satellite infrared imagery Chris Velden, Tim Olander and Ray Zehr Weather and Forecasting, 1998, Vol. 13, pp. 172-186

  10. Advanced Dvorak TechniqueADT History: The AODT Step Two: The Advanced Objective Dvorak Technique (AODT)

  11. Advanced Dvorak Technique ADT History: The AODT • Expand and Improve the ODT • Increase analysis intensity range and precision • Allow for analysis of all ranges of intensities at/above TD stage • Addition of new scene type classifications and analysis scheme • Curved Band using 10° Log Spiral technique • Additional Eye scene types • Modified cloud region temperature calculation (to help identify cloud symmetry) • Integrate modified DvT Rule 8 intensity growth/decay constraints • Provide completely automated analysis capability • Remove final subjective element of ODT technique: the storm center determination/selection (replace analyst positioning using a mouse/curser with an objective Laplacian-based technique to search for localized and correlated bi-directional Tb gradients) • Implement latitude bias adjustment for final MSLP estimates • Regression-based on relationship of the change of tropopause height (and cloud top temps) with latitude (Kossin and Velden, 2004, MWR)

  12. Advanced Dvorak TechniqueADT History: The ADT Step Three: The Advanced Dvorak Technique (ADT)

  13. Advanced Dvorak Technique ADT History: The ADT • Improve existing AODT methodology, and advance the algorithm beyond scope of the DvT • Integrate new intensity relationships • Derive regression-based equations for eye and central dense overcast (CDO) scene types (discard look-up tables) • Identify new environmental variables for regression equations • Implement “Scene Score” calculation to determine current scene type using previous scene type and other environmental values • Helps eliminate unrealistic scene type jumps • Utilize new automated storm center determination process • Implement forerunner to Wimmers/Velden ARCHER scheme (2010, JAMC) • Examines spiral band structure of entire IR cloud top temperature field • Searches for eye features using advanced ring fitting analysis scheme • Can identify and discard most “false eye” situations • Scheme works primarily in T# range 3.5 and greater • Defaults to interpolation of OFC track forecast at weaker intensities

  14. Advanced Dvorak TechniqueADT History: The ADT The Advanced Dvorak Technique: Continued development of an objective scheme to estimate tropical cyclone intensity using geostationary infrared satellite imagery Timothy Olander and Christopher Velden Weather and Forecasting, 2007, Vol. 22, pp. 287-298

  15. Advanced Dvorak Technique ADT History: The ADT • New: Exploit additional satellite sensor information • Utilize externally-derived Passive Microwave (PMW) Intensity “Score” values during CDO events • ADT intensities typically level out during CDO events until eye feature appears in IR imagery • PMW imagery can often identify the organization of eye features below cirrus shield in the developing TC stages • PMW score is determined from objectively analyzed TC structure using 85GHz, and based on empirically-derived thresholds, can result in the over-ride of the ADT-based T# (depending on score, two different T# intensity estimates can be assigned (either T# = 4.3 or 5.0)) • Additional logic in ADT algorithm “merges” new PMW-derived T# values into existing history file to eliminate unnatural intensity jumps (linear extrapolation back 12 hours from PMW estimate point). New logic also linearly increments the PMW value forward in proportion to DvT model Tnum expected growth.

  16. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Validation • Current Status and Availability • Looking Towards the Future

  17. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Automated Storm Centering • PMW Score • Knaff/Courtney/Zehr Wind>Pressure • Validation • Current Status and Availability • Looking Towards the Future

  18. Advanced Dvorak TechniqueAutomated Storm Centering Storm center determination • Utilize IR-Window Imagery (No VIS yet) • Spiral Centering • First guess interpolated from official TC forecast • Fits 5° log spiral to grid points within search radius around first guess position • Calculates Tb gradients along spiral; determines position and rotation where minimum exists • Ring Fitting • Spiral Centering position serves as first guess • Fits series of rings with different radii at grid points within search region • Searches for single ring that fits maximum Tb gradients

  19. Advanced Dvorak TechniqueAutomated Storm Centering • Spiral Centering • Fits 5° log spiral vector field to the IR image • Calculates a grid of scores that indicates the alignment between the spiral field and the IR Tb gradients (maximum at the spiral center • Ring Fitting • Calculates a grid of scores that indicates the best fit to a range of possible ring positions and diameters (maximum at the eye center)

  20. Advanced Dvorak TechniqueAutomated Storm Centering

  21. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Automated Storm Centering • PMW Score • Knaff/Courtney/Zehr Wind>Pressure • Validation • Current Status and Availability • Looking Towards the Future

  22. Advanced Dvorak TechniquePMW Intensity Estimate “Score” Summary • As briefly mentioned earlier, a recent major ADT algorithm improvement utilizes external passive microwave (PMW) information to aid in detection of tropical cyclone eye/eyewall formation when the ADT objective scene identification scheme (relying on IR alone) cannot discern developing eye features due to high-level overcast. • ADT algorithm can struggle with this scenario and the T#s often “plateau”. Coincident PMW data can view through much of the overcast and in many cases discern an organizing eye structure. • Based on the amount of eyewall organization (wrap) and strength, a PMW “score” is calculated. • If the score exceeds pre-determined thresholds, the value is passed to the ADT, where it is converted to a T# and over-rides the IR-based T#. • Currently this scheme is only utilized in the developing stages of TCs

  23. Advanced Dvorak Technique PMW Intensity Estimate Score • Uses the 85GHz brightness temperature signal to deduce the vigor and organization of the developing eyewall/eye, and calculate an intensity score • Successful in loosely differentiating between storms • Greater than ~72 knots • Greater than ~90 knots • If thresholds are exceeded, PMW scores are converted to either T# of 4.3 or 5.0 in the ADT • The scheme has been operating in the ADT since 2008 Eyewall temperatures Warmest eye pixel Hurricane Dolly, 23 July 2008 1126 UTC DMSP SSM/I 85GHz (H) brightness temperature

  24. Advanced Dvorak Technique PMW Intensity Estimate Score More intense; Closer to Best Track More accurate during rapid intensification

  25. Advanced Dvorak Technique PMW Intensity Estimate Score Eliminated false intensity “plateau”; Closer to Best Track More closely follows rapid intensification; More accurate maximum intensity resulted

  26. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Automated Storm Centering • PMW Score • Courtney/Knaff Wind>Pressure • Validation • Current Status and Availability • Looking Towards the Future

  27. Advanced Dvorak TechniqueCourtney/Knaff Wind>Pressure • Based on Courtney and Knaff (2009) • Adapting the Knaff and Zehr wind-pressure relationship for operational use in Tropical Cyclone Warning Centres, Australian Meteorological and Oceanographic Journal, 58, pp. 167-179 • ADT final MSLP estimate: Starts with the derived T# and Vmax, then utilizes information from real-time ATCF CARQ files provided by OFCs (NHC or JTWC) • R34 = Average of ATCF RAD1-RAD4 wind radii (in nmi) for 34 knot wind threshold (gale radius) • MSLP = Pressure (in mb) of outermost closed isobar (ATCF POUTER value) • ROCI = Radius of outermost closed isobar (ATCF ROUTER value, in nmi) to estimate R34 value if no 34-knot wind radii are available • R34est = (0.354 * ROCI) + 13.3 • ADT also uses climatological storm speed value of 11 knots • Andrew Burton will discuss C/K methodology in greater detail later…

  28. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Validation • Current Status and Availability • Looking Towards the Future

  29. Advanced Dvorak TechniqueADT Validation (Vmax, vs. Recon) Comparison of latest ADT version (v8.1.3, with PMW) and previous version (v7.2.3, w/o PMW) 7.2.3 Mean Error 7.2.3 Bias 8.1.3 Mean Error 8.1.3 Bias Intensity range affected most by PMW “eye score” addition

  30. Advanced Dvorak TechniqueADT Validation: Comparisons with SAB DvT • NORTH ATLANTIC – 2010 TC Season • Independent comparisons between ADT and SAB intensity estimates • ADT and SAB estimates w/in +/- 30 minutes • Closest NHC Best Track intensity (co-located w/ aircraft reconnaissance in situ measurement w/in 2 hours) 106 total matches (homogeneous) bias aae stdv SAB:CI# -0.22 0.48 0.57 SAB:Win -1.40 7.77 10.23 SAB:MSL 5.01 8.20 9.78 ADT:CI# -0.02 0.58 0.73 ADT:Win 2.59 8.22 10.47 ADT:MSL 2.22 8.94 11.35 Note: SAB analysts do have access to, or awareness of, the recon reports. While this influence is difficult to quantify, it offers a stringent comparison test for the ADT.

  31. Advanced Dvorak TechniqueADT Validation: Comparisons with SAB DvT • EAST/CENTRAL PACIFIC – 2010 TC Season • Independent comparisons between ADT and SAB intensity estimates • ADT and SAB estimates w/in +/- 30 minutes • Closest NHC Best Track intensity 126 total matches (homogeneous) bias aae stdv SAB:CI# -0.05 0.33 0.43 SAB:Win 0.48 5.91 8.54 SAB:MSL 0.08 4.59 6.73 ADT:CI# -0.07 0.28 0.36 ADT:Win -0.38 5.94 7.73 ADT:MSL 0.88 3.81 5.36 Note: NHC is using the ADT increasingly, especially in the EPAC. While difficult to quantify, their BT may reflect ADT influences.

  32. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Validation • Current Status and Availability • Looking Towards the Future

  33. Advanced Dvorak TechniqueCurrent Status and Availability • Current ADT Status and Availability • Routinely utilized by several OFCs from CIMSS web site • http://tropic.ssec.wisc.edu/real-time/adt/ • Version 8.1.3 will be active on the CIMSS web site starting 1 May, 2011 • Efforts underway at SAB to integrate this version into operations there, to provide estimates via ATCF. • Completion date uncertain • Portable version now available (license req.)

  34. Advanced Dvorak TechniqueCurrent Status and Availability ADT real-time homepage : http://tropic.ssec.wisc.edu/real-time/adt

  35. Advanced Dvorak TechniqueCurrent Status and Availability **************************************************** UW - CIMSS ADVANCED DVORAK TECHNIQUE ADT-Version 8.1.3 Tropical Cyclone Intensity Algorithm ----- Current Analysis ----- Date : 28 AUG 2005 Time : 154500 UTC Lat : 26:14:25 N Lon : 88:20:05 W CI# /Pressure/ Vmax 6.8 / 926.0mb/134.8kt Final T# Adj T# Raw T# 6.7 6.7 6.7 Latitude bias adjustment to MSLP : -0.6mb Estimated radius of max. wind based on IR : 33 km Center Temp : +20.2C Cloud Region Temp : -69.9C Scene Type : EYE Positioning Method : RING/SPIRAL COMBINATION Ocean Basin : ATLANTIC Dvorak CI > MSLP Conversion Used : ATLANTIC Tno/CI Rules : Constraint Limits : NO LIMIT Weakening Flag : ON Rapid Dissipation Flag : OFF **************************************************** ADT real-time homepage http://tropic.ssec.wisc.edu/real-time/adt ADT Current Intensity “Bulletin”

  36. Advanced Dvorak TechniqueCurrent Status and Availability ===== ADT-Version 8.1.3 ===== --------Intensity------- -Tno Values-- ---Tno/CI Rules--- -Temperature- Time Final/MSLPLat/Vmax Fnl Adj Ini Cnstrnt Wkng Rpd Cntr Mean Scene EstRMW MW Storm Location Fix Date (UTC) CI MSLP /BiasAdj/(kts) Tno Raw Raw Limit Flag Wkng Region Cloud Type (km) Score Lat Lon Mthd Comments 2005AUG23 211500 2.0 1009.0/ +0.0 / 30.0 2.0 2.0 2.0 NO LIMIT OFF OFF -4.76 -35.41 CRVBND N/A N/A 23.25 75.44 FCST 2005AUG23 214500 2.1 1008.2/ +0.0 / 31.0 2.1 2.2 2.6 0.2T/hour OFF OFF 5.84 -34.85 CRVBND N/A N/A 23.28 75.49 FCST 2005AUG23 221500 2.1 1008.2/ +0.0 / 31.0 2.1 2.2 2.5 0.2T/hour OFF OFF 5.84 -33.57 CRVBND N/A N/A 23.30 75.54 FCST 2005AUG23 224500 2.1 1008.2/ +0.0 / 31.0 2.1 2.3 2.3 NO LIMIT OFF OFF 3.84 -34.04 CRVBND N/A N/A 23.33 75.58 FCST 2005AUG23 231500 2.2 1007.4/ +0.0 / 32.0 2.2 2.4 2.7 0.2T/hour OFF OFF 0.04 -34.42 CRVBND N/A N/A 23.36 75.63 FCST 2005AUG23 234500 2.2 1007.4/ +0.0 / 32.0 2.2 2.3 2.3 NO LIMIT OFF OFF 6.74 -33.37 CRVBND N/A N/A 23.39 75.68 FCST 2005AUG24 001500 2.2 1007.4/ +0.0 / 32.0 2.2 2.3 2.3 NO LIMIT OFF OFF 13.54 -32.66 CRVBND N/A N/A 23.41 75.72 FCST 2005AUG24 004500 2.2 1007.4/ +0.0 / 32.0 2.2 2.3 2.3 NO LIMIT OFF OFF 14.74 -30.82 CRVBND N/A N/A 23.43 75.77 FCST <records deleted> 2005AUG27 154500 4.8 973.5/ -0.1 / 84.8 4.6 4.9 4.9 NO LIMIT ON OFF -53.56 -68.93 EMBC N/A N/A 24.49 85.25 SPRL 2005AUG27 161500 4.8 973.5/ -0.1 / 84.8 4.7 5.0 5.0 NO LIMIT ON OFF -53.86 -68.15 EMBC N/A N/A 24.50 85.31 SPRL 2005AUG27 164500 4.8 973.5/ -0.1 / 84.8 4.8 5.1 5.1 NO LIMIT OFF OFF -60.06 -69.29 EMBC N/A N/A 24.51 85.49 SPRL 2005AUG27 171500 4.8 973.5/ -0.1 / 84.8 4.8 5.0 5.0 NO LIMIT OFF OFF -62.66 -69.35 EMBC N/A N/A 24.53 85.67 SPRL 2005AUG27 174500 4.8 973.5/ -0.1 / 84.8 4.8 4.6 4.6 NO LIMIT OFF OFF -68.36 -70.79 UNIFRM N/A N/A 24.64 85.75 SPRL 2005AUG27 181500 4.8 973.4/ -0.2 / 84.8 4.8 4.5 4.5 NO LIMIT OFF OFF -67.06 -69.50 UNIFRM N/A N/A 24.76 86.03 SPRL 2005AUG27 184500 4.8 973.5/ -0.1 / 84.8 4.8 5.1 5.1 NO LIMIT OFF OFF -65.36 -71.15 EMBC N/A N/A 24.68 85.85 SPRL 2005AUG27 191500 4.8 973.5/ -0.1 / 84.8 4.8 4.7 4.7 NO LIMIT OFF OFF -68.76 -73.14 UNIFRM N/A N/A 24.60 85.57 SPRL 2005AUG27 194500 4.8 973.5/ -0.1 / 84.8 4.8 4.7 4.7 NO LIMIT OFF OFF -68.36 -73.25 UNIFRM N/A N/A 24.63 85.61 SPRL <records deleted> 2005AUG28 104500 6.7 929.0/ -0.4 /132.2 6.7 6.8 6.8 NO LIMIT OFF OFF 19.64 -70.90 EYE 30 IR N/A 25.74 87.56 COMBO 2005AUG28 111500 6.7 929.0/ -0.4 /132.2 6.7 6.7 6.7 NO LIMIT OFF OFF 19.44 -71.08 EYE 31 IR N/A 25.68 87.64 COMBO 2005AUG28 114500 6.8 926.1/ -0.4 /134.8 6.8 6.8 6.8 NO LIMIT OFF OFF 19.74 -71.74 EYE 30 IR N/A 25.73 87.72 COMBO 2005AUG28 121500 6.8 926.1/ -0.4 /134.8 6.7 6.7 6.7 NO LIMIT ON OFF 18.54 -71.46 EYE 31 IR N/A 25.76 87.78 COMBO 2005AUG28 124500 6.8 926.1/ -0.5 /134.8 6.7 6.7 6.7 NO LIMIT ON OFF 18.54 -71.12 EYE 32 IR N/A 25.88 87.81 COMBO 2005AUG28 131500 6.8 926.1/ -0.5 /134.8 6.7 6.8 6.8 NO LIMIT ON OFF 19.64 -72.01 EYE 32 IR N/A 25.90 87.97 COMBO 2005AUG28 134500 6.8 926.1/ -0.5 /134.8 6.7 6.8 6.8 NO LIMIT ON OFF 20.24 -71.25 EYE 32 IR N/A 25.93 88.02 COMBO 2005AUG28 141500 6.8 926.1/ -0.5 /134.8 6.7 6.7 6.7 NO LIMIT ON OFF 19.94 -70.71 EYE 31 IR N/A 25.97 88.08 COMBO 2005AUG28 144500 6.8 926.0/ -0.6 /134.8 6.7 6.8 6.8 NO LIMIT ON OFF 19.34 -70.99 EYE 31 IR N/A 26.11 88.15 COMBO 2005AUG28 151500 6.8 926.0/ -0.6 /134.8 6.7 6.6 6.6 NO LIMIT ON OFF 20.64 -69.05 EYE 32 IR N/A 26.26 88.22 COMBO <records deleted) 2005AUG29 084500 6.3 938.8/ -1.4 /122.2 5.8 6.2 6.2 NO LIMIT ON OFF 13.04 -66.90 EYE 28 IR N/A 28.81 89.54 COMBO 2005AUG29 091500 6.3 938.8/ -1.4 /122.2 5.9 6.2 6.2 NO LIMIT ON OFF 15.34 -66.15 EYE 28 IR N/A 28.92 89.54 COMBO 2005AUG29 094500 6.3 938.8/ -1.4 /122.2 5.9 6.2 6.2 NO LIMIT ON OFF 12.54 -66.08 EYE 28 IR N/A 29.03 89.54 COMBO 2005AUG29 101500 6.3 938.7/ -1.5 /122.2 6.0 6.0 6.0 NO LIMIT ON OFF 13.84 -63.94 EYE 29 IR N/A 29.14 89.54 COMBO 2005AUG29 104500 6.3 938.7/ -1.5 /122.2 6.0 5.8 5.8 NO LIMIT ON OFF 14.44 -61.50 EYE 30 IR N/A 29.25 89.54 COMBO 2005AUG29 111500 0.0 0.0/ +0.0 / 0.0 0.0 0.0 0.0 N/A N/A 99.50 99.50 LAND N/A N/A 29.37 89.54 COMBO 2005AUG29 114500 6.3 938.6/ -1.6 /122.2 6.0 5.6 5.6 NO LIMIT ON OFF 12.54 -59.59 EYE 30 IR N/A 29.49 89.43 COMBO 2005AUG29 121500 6.3 938.6/ -1.6 /122.2 5.8 5.5 5.5 NO LIMIT ON OFF 14.34 -58.01 EYE 31 IR N/A 29.67 89.54 COMBO 2005AUG29 124500 6.3 938.5/ -1.7 /122.2 5.7 5.5 5.5 NO LIMIT ON OFF 11.84 -59.13 EYE 29 IR N/A 29.74 89.55 COMBO 2005AUG29 131500 6.3 938.5/ -1.7 /122.2 5.6 5.6 5.6 NO LIMIT ON OFF 11.94 -60.14 EYE 30 IR N/A 29.81 89.55 COMBO 2005AUG29 134500 0.0 0.0/ +0.0 / 0.0 0.0 0.0 0.0 N/A N/A 99.50 99.50 LAND N/A N/A 30.00 89.56 COMBO 2005AUG29 141500 6.3 938.5/ -1.7 /122.2 5.5 5.7 5.7 NO LIMIT ON FLG -1.56 -61.88 EYE 27 IR N/A 30.00 89.45 COMBO 2005AUG29 144500 0.0 0.0/ +0.0 / 0.0 0.0 0.0 0.0 N/A N/A 99.50 99.50 LAND N/A N/A 30.32 89.56 COMBO Utilizing history file /home/tlo/odt/ADTV8.1.3WV/history/2005KATRINA.ODT Successfully completed listing ADT real-time homepage http://tropic.ssec.wisc.edu/real-time/adt ADT History File Listing --------Intensity------- -Tno Values-- ---Tno/CI Rules--- -Temperature- Time Final/MSLPLat/Vmax Fnl Adj Ini Cnstrnt Wkng Rpd Cntr Mean Scene EstRMW MW Storm Location Fix Date (UTC) CI MSLP /BiasAdj/(kts) Tno Raw Raw Limit Flag Wkng Region Cloud Type (km) Score Lat Lon Mthd 2005AUG28 104500 6.7 929.0/ -0.4 /132.2 6.7 6.8 6.8 NO LIMIT OFF OFF 19.64 -70.90 EYE 30 IR N/A 25.74 87.56 COMBO

  37. Advanced Dvorak TechniqueCurrent Status and Availability ADT Time Series Intensity Plot

  38. Advanced Dvorak TechniquePresentation Overview • Historical Overview • Latest Advancements • Validation • Current Status and Availability • Looking Towards the Future

  39. Advanced Dvorak Technique Looking Towards the Future • Address current ADT biases and weaknesses • Shear scenes (weaker systems) • Curved Band analyses (employ regression approach?) • Weak bias in storms with Vmax >130kts • Passage over land and re-emergence • Exploit additional satellite sensor information • Differencing of Infrared and Water Vapor imagery shows promise in multiple areas • Correlation improvements for CDO and other scene type intensity estimates through regression analysis • Can aid in automated storm center determination • Shows potential in rapid intensification prediction

  40. Note similarities between derived IR-WV image and NWS radar identifying strongest convective regions Recon Center Interpolated NHC forecast IR-WV product correctly identifies possible forming eye region IR-WV selected storm center Uniform CDO in IR-Window covering storm center Advanced Dvorak TechniqueIR-WV Channel Differencing Stretched Enh IR Image (IR-WV locations only) IR Image Derived IR-WV Image IR Image (w/ BD enh) NOAA/NWS Radar

  41. Advanced Dvorak TechniqueIR-WV Channel Differencing Tropical cyclone convection and intensity analysis using differenced infrared and water vapor imagery Timothy Olander and Christopher Velden Weather and Forecasting, 2009, Vol. 24, pp. 1558-1572

  42. Advanced Dvorak TechniqueOther ADT Research Avenues • Expand ADT to initiate and operate on “Invest” systems • I.E., attempt to objectively identify DvT T#1.0-1.5 convective disturbances • Test and possibly integrate a new objective algorithm developed by Chris Hennon et al. at North Carolina State Univ. which detects and tracks tropical cloud clusters related to tropical cyclogenesis • Implementation and initial testing will begin this summer

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