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Rolf LanglandNRL-Monterey

Plans for Evaluation of Lidar Wind Observations at NRL-Monterey

Working Group on Space-Based Lidar Winds

05 Feb 2008

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1. T-PARC plans - Falcon and P-3

2. Data Assimilation Issues

3. Potential Benefit of Space-Based Lidar Wind Observations

Outline of Talk

3 airport base: Atsugi, Japan (tbc with US Navy)

alternative airports: Okinawa, Misawa, Iwo Jima (?), Korea (?)

flight time: 90 h plus 30 h for transfer

planned schedule (depending on funding)total: 7-8 weeks incl. transfer/integrationtakeoff in Germany: 21 Aug 2008arrival in Japan: 24/25 August 2008last day in Japan: 4 October (~6 weeks in Japan)arrival in Germany: 7/8 October

real-time data: dropsondesnear real-time: aircraft in-situ, lidar quicklooksnon-realtime: lidar data lidar

aircraft manager: Andrea.Hausold@DLR.DE

max. range: 1350-1600 NM max altitude: 12.8 km (42 kft)

Falcon plans: T-PARC 2008

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wind lidar data:horiz resolution: ~10 kmvert. resolution: 100 m

number of wind profiles in Japan: 5400

number of profiles on transfer though Siberia: 1800(the permission for observations in Russia is not certain yet)

expected lidar coverage based on the experience from A-TReC35% for 10-km horizontal resolution55% for 40-km horizontal resolution

Research interests:observation targetingextratropical transition of tropical cyclones and downstream impactvalue of new observing systems (lidars)tropical moisture export

Falcon plans: T-PARC 2008

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• Targeting Guidance for TC forecasts – NOGAPS singular vectors

• Adjoint-based observation impact evaluation (after reanalysis with T-PARC lidar observations)

• Conventional observation addition and denial forecast experiments (after reanalysis)

NRL plans: T-PARC 2008

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NOGAPS Singular Vector Targeting Guidance

Observation Target Time Forecast Verification Time

Target area for additional observations

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Example of NOGAPS-NAVDAS Adjoint-based Observation Impact

Reduction Increase

Effect of observations on 24-hr fcst error norm

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Data Assimilation Issues for Lidar Observations

• Procedures for super-obbing or thinning of raw data • Quality control – innovation checks

• Specification of observation and representativeness error

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Potential Benefits of Space-Based Lidar Observations

• Will observations fill gaps in current observing network (esp. 500-800 mb layer?)

• Will observations be in forecast error source regions?

• More accurate than other wind observations?

• How much data will be provided, and how frequently ?

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Current GEOSAT Wind Coverage

300 – 500 mb 500 – 700 mb

700 – 800 mb 800 – 900 mb

Impact of JMA – MTSAT wind observations

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Error Source Regions – Sensitivity to Initial Conditions

January 2007 – 0000 and 1200UTC Analyses

NOGAPS - NAVDAS

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60N

20N

130W140E

Observations in the North Pacific Region

North Pacific Ocean

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0

5000

10000

15000

20000

25000

30000 SatwindAMSU-ASSMI/PRHRaobAircraftLand SfcScatwindWindsatModisShip SfcSSMI/Wnd

04 Feb 2007 (00,06,12,18UTC) Total = 97,183 obs = 6.7% of global data

North Pacific region observation data count - NAVDAS

Ob Data Count

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05000

1000015000200002500030000350004000045000

Wind

Moisture

Radiance

Temperature

Height

Ob Data Count

North Pacific Region Observation Variable Count - NAVDAS

04 Feb 2007 (00,06,12,18UTC)

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-8

-7

-6

-5

-4

-3

-2

-1

0SatwindAMSU-ASSMI/PRHRaobDropsondeAircraftLand SfcScatwindWindsatModisShip SfcSSMI/Wnd

North Pacific observation impact sum - NAVDAS

1-31 Jan 2007 (00UTC analyses)Change in 24h moist total energy error norm (J kg-1)

Error Reduction

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-10

-9-8

-7

-6-5

-4-3

-2-1

0 SatwindAMSU-ASSMI/PRHRaobDropsondeAircraftLand SfcScatwindWindsatModisShip SfcSSMI/Wnd

Error Reduction

(x 1.0e5)

Change in 24h moist total energy error norm (J kg-1)

1-31 Jan 2007 (00UTC analyses)

North Pacific forecast error reduction per-observation

Ship Obs

Targeted dropsondes = high-impact per- ob, low total impact

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End of Presentation !

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Excluding Aircraft & Satwind Observations

Global observation density - NAVDAS 04 Feb 2007 (00,06,12,18UTC)

Excluding Aircraft Observations

Number of data in 5deg x 5deg lat-lon areas

All Observations

More satellite data over ocean

Than over land