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The Operational Impact of and Future The Operational Impact of and Future Requirements for Satellite Ocean Surface Requirements for Satellite Ocean Surface

Vector Winds in Tropical Cyclone AnalysisVector Winds in Tropical Cyclone Analysis

Michael BrennanMichael Brennan11, Richard Knabb, Richard Knabb11, Paul Chang, Paul Chang22, , Joseph SienkiewiczJoseph Sienkiewicz33, Zorana Jelenak, Zorana Jelenak22, Kevin Schrab, Kevin Schrab44

1NOAA/NWS/NCEP/NHC, 2NOAA/NESDIS/STAR, 3NOAA/NWS/NCEP/OPC, 4NOAA/NWS/OST

61st Interdepartmental Hurricane Conference6 March 2007

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Impact of OSVW Data on TC Analysis Impact of OSVW Data on TC Analysis and Forecasting and Forecasting

• QuikSCAT data available in operational workstations at NHC since 2000

• Some information on TC intensity, especially for tropical storms, but not major hurricanes

– Limited by instrument resolution

– Interpretation complicated by rain contamination

• Improved detection/tracking of TC centers for analysis and model initialization

• Often only source of outer wind radii information for open ocean systems affects watch/warning areas

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Use of QuikSCAT at NHCUse of QuikSCAT at NHC

Percentage of NHC Tropical Cyclone Discussions Mentioning QuikSCAT

4.9

6.2

9.0

10.511.0

16.2

22.0

6.7

15.516.7 17.1

15.1

18.118.8

0.0

5.0

10.0

15.0

20.0

25.0

2000 2001 2002 2003 2004 2005 2006

Year

Pe

rce

nta

ge

Atlantic

E Pacific

Intensity62%

Center Fixing/Identification

21%

Wind Radii17%

Based on 2003–2006 Tropical Cyclone Discussions

Does not account for instances where QSCAT used but not explicitly mentioned in TCD

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NOAA OSVW Requirements NOAA OSVW Requirements WorkshopWorkshop

5–7 June 2006 – NHC, Miami, FL5–7 June 2006 – NHC, Miami, FL

Goals1. Summarize utility and impact of currently

available satellite OSVW data in operational weather forecasting

2. Define NOAA’s operational OSVW requirements

3. Explore sensor/mission concepts using proven remote sensing technologies to meet these requirements

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Who Else is Using OSVW?Who Else is Using OSVW?Workshop ParticipantsWorkshop Participants

• NHC, CPHC, JTWC– TC analysis and forecasting

• NWS Ocean Prediction Center, NHC’s Tropical Analysis and Forecast Branch (TAFB), NWS coastal WFOs, DoD– Marine forecasts, warnings, and analyses– Identification of hurricane force extratropical cyclones at OPC

• NOAA/NESDIS – Develop retrieval algorithms, data processing, real time data distribution

• NCEP/Environmental Modeling Center, FNMOC, ECMWF– Data assimilation for NWP modeling

• NASA/JPL• Academic and research communities• Private sector marine forecasters, recreational mariners

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Operational RequirementsOperational Requirements• All-weather retrievalsAll-weather retrievals

– Accurate retrievals in rainAccurate retrievals in rain

• Accuracy levied upon 10-m 1-min sustained wind

– Speed: +/- 2 kt in 0–165 kt wind range

– Direction:• +/- 10° (2 σ) (10–165 kt)

• +/- 20° (2 σ) (4–10 kt)

• Revisit time: 6 h (1–3 h goal)– Interval between measurements at

particular point on ocean surface

Helene 23 September 2006

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Operational RequirementsOperational Requirements• Reduce time from measurement to

product availability (product latency) to 45–60 min

– 15 min goal

• 2.5 km x 2.5 km spacing between unique wind vector retrievals (1 km goal)

• Retrievals within 2.5 km of coast (1 km goal)

• Data delivered into operational workstations (N-AWIPS/AWIPS) and data assimilation systems

• Product documentation/tutorials/training

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13km resolutionMax wspd 120.7 ktsRms 5.71 kts

Available Today!

2km resolutionMax wspd 134.3 ktsrms 2.14 kts

Definitely Achievable

35km resolutionMax wspd 106.1 ktsrms 8.88 kts

70km resolutionMax wspd 91.0 ktsrms 12.50 kts

Likely range of NPOESS

solution

Instrument Resolution Affects Ability to Measure Maximum Wind Instrument Resolution Affects Ability to Measure Maximum Wind (Max retrievable wind speed does not account for rain effects)(Max retrievable wind speed does not account for rain effects)

1km resolutionMax wspd 137.8 ktsTrue Wind Field

User Requested

25km resolutionMax wspd 105.9 ktsrms 7.72 kts

Available Today!

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Current and Future OSVW MissionsCurrent and Future OSVW Missions

AMI/ERS-2

Seawinds/QuikSCAT

WINDSAT CMIS/NPOESS-C1

97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15

In orbit Approved• Planned foreign missions• Unknown instrument designs• Research missions• Questionable data availability (no agreements in place to share data)

SeaWINDS/ADEOS-II

895 km 1700 km

500 km

1600 km

2 x 550 km w/ 768-km nadir gap

~60% of QuikSCAT coverage

X

No CMIS on NPOESS C-1A less capable CMIS-successor is

planned beginning with C-2 in 2016.

China - HY-2

India - OceanSat-2?ASCAT/METOP – 3-satellite series

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Next Generation Ocean Vector Next Generation Ocean Vector Wind Mission (XOVWM)Wind Mission (XOVWM)

• Recommended to NOAA by National Academies’ Decadal Survey

• XOVWM combines available technology and measurement heritage represents order of magnitude advanceadvance in scientific and operational capability with moderate risk and cost

– Ku-band scatterometer (high resolution)

– C-band scatterometer (less sensitivity to rain)

– Multi-frequency polarimetric radiometer (provide rain corrections)

• Meeting revisit time requirements (6 h) would require at least 2, and probably 3 satellites

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Key RecommendationsKey Recommendations• Interagency Strategic Research Plan for Tropical Cyclones: The

Way Ahead, February 2007– “Due to the importance of OSVW data—for use by tropical cyclone

forecasters and in tropical cyclone NWP systems—the JAG/TCR strongly endorses the development and acquisition of a capability to meet the OSVW observation requirements. This capability is absolutely critical to meeting the operational needs of the tropical cyclone forecast and warning centers…”

• Sixth WMO International Workshop on Tropical Cyclones (IWTC-VI), San José, Costa Rica, 21-30 November 2006– “IWTC-VI recommends that the WMO Space Program strongly

endorse the specific recommendations of the US National Oceanic and Atmospheric Administration Operational Satellite Ocean Surface Wind Vector Winds Requirements Workshop Report….”

• Majority Report, NOAA Science Advisory Board Hurricane Intensity Research Working Group, 8 October 2006– “Combining a broad range of atmospheric and oceanic observing

techniques provides the best overall observing capacity. The current mix of satellites, manned aircraft, buoys, radar, etc, should be maintained as a critical component of the overall hurricane forecasting process.”

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SummarySummary

• Currently available operational OSVW data have led to significant improvements in TC analysis and forecasting

– Advances in marine analyses, forecasts, and warnings from high seas to coastal waters

• NOAA has no plans to launch an operational OSVW mission to maintain current data quality after QuikSCAT

– Cannot afford take step backward and lose improvements made!

• High-quality OSVW data critical to addressing hurricane intensity problem

– Analysis tool for inner core structure for model input and validation of model output

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SummarySummary

• OSVW data from NPOESS MIS likely of limited utility for TC analysis

– Based on experience with WindSat at NHC

– Resolution not sufficient for TC analysis needs, maybe no wind direction?

• Future international research missions

– Availability and quality of data unknown

• Place XOVWM on accelerated timetable

– Minimize post-QuikSCAT gap in high-quality OSVW data

– Some of cost could be defrayed by limiting the ocean vector winds capabilities of MIS

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Goals for Continued use of OSVW Goals for Continued use of OSVW Data in OperationsData in Operations

• Short termShort term– Push QuikSCAT capabilities to limits– Attempt to improve WindSat retrievals– Expedite data processing, distribution,

and training for ASCAT

• Mid TermMid Term– Maintain operational availability of

QuikSCAT data through instrument life span beyond FY09

– FY09 – Study and design of XOVWM mission (sensor, satellite bus and ground system)

• Long TermLong Term– FY10–12 – procurement, integration,

and testing of XOVWM– FY13 – XOVWM mission launch and

calibration/validation

ASCAT Coverage (courtesy COMET/EUMETSAT)

QuikSCAT launch (courtesy NASA)

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Activity since NOAA WorkshopActivity since NOAA Workshop• July 2006

– Attended NASA Ocean Vector Winds Science Team meeting• August 2006

– Workshop report finalized and distributed• September 2006

– Briefed the Technical Director for the Oceanographer of the Navy • October 2006

– Briefed NWS Director Johnson– Attended NPOESS Polar Max meeting

• November 2006– Briefed NOAA CFO and Program Analysis and Evaluation Director

• December 2006– Presentations given at AGU Fall Meeting and NOAA Hurricane

Conference– Interactions with NASA about next generation OSVW mission

• January 2007– Briefed Vice Admiral Lautenbacher– Presentation given at AMS Annual Meeting

• February 2007– Briefed NOAA Observing Systems Council

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Feedback from DoDFeedback from DoD

• DoD support for XOVWM would bolster efforts to move toward NOAA’s operational requirements and limit post-QuikSCAT data gap

• Reference IHC Action Item #2: “Satellite Ocean Surface Vector Winds Operational Impacts and Requirements” – Thursday

• Informal meeting in the hall after this session