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NOAA P-3 Status for BAMEXNOAA P-3 Status for BAMEX 148 flight hours approved148 flight hours approved 20 May - 6 July20 May - 6 July Chief Scientists:Chief Scientists:

– Jorgensen: 20 May - 6 July, except 27-30 May & 22-24 June (Jorgensen: 20 May - 6 July, except 27-30 May & 22-24 June (maybemaybe))

– Ziegler: 20 May - 3 JuneZiegler: 20 May - 3 June

– Smull: 2 June - 24 JuneSmull: 2 June - 24 June

Doppler Scientists:Doppler Scientists:– Jorgensen: 20 May - 6 July, except 27-30 May & 22-24 June (Jorgensen: 20 May - 6 July, except 27-30 May & 22-24 June (maybemaybe))

– Ziegler: 20 May - 3 JuneZiegler: 20 May - 3 June

– Smull: 2 June - 24 JuneSmull: 2 June - 24 June

Cloud Physics Scientists:Cloud Physics Scientists:– Greg McFarquharGreg McFarquhar

– Robert RauberRobert Rauber

– Brian JewettBrian Jewett

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Key P-3 ObjectivesKey P-3 Objectives NOAA P-3:NOAA P-3:

– Airborne Doppler radar mapping of 3-D flowsAirborne Doppler radar mapping of 3-D flows

– Cloud Physics observations from ~5°C to ~-15°CCloud Physics observations from ~5°C to ~-15°C

– Multiple snapshots of rear inflow system structureMultiple snapshots of rear inflow system structure

– Coordinated legs with NRL P-3 where possible (quad Doppler)Coordinated legs with NRL P-3 where possible (quad Doppler)

– Straight-line flight tracks in bow-echo “rear” at 18,000 ft (~-15°C)Straight-line flight tracks in bow-echo “rear” at 18,000 ft (~-15°C)

NRL P-3:NRL P-3:– Airborne Doppler (ELDORA) radar mapping of convective lineAirborne Doppler (ELDORA) radar mapping of convective line

– Multiple snapshotsMultiple snapshots

– Coordinated legs with NOAA P-3 where possible (quad-Doppler)Coordinated legs with NOAA P-3 where possible (quad-Doppler)

– Flight level as low as practicalFlight level as low as practical

– Straight-line flight tracks bestStraight-line flight tracks best

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Aircraft HazardsAircraft Hazards NOAA P-3:NOAA P-3:

– Lightning strikes near 0°C!Lightning strikes near 0°C!– Wind shear at base of anvil near top of rear inflowWind shear at base of anvil near top of rear inflow– Aircraft charging in iceAircraft charging in ice– Icing in strong stratiform regionsIcing in strong stratiform regions

NRL P-3:NRL P-3:– Strong convection near leading edge - avoid in spite of Strong convection near leading edge - avoid in spite of

no LF radar!no LF radar!– Tracks within ~5 na mi. of leading edgeTracks within ~5 na mi. of leading edge– Tornadic activity usually from the apex of the bow Tornadic activity usually from the apex of the bow

northward and in “tail end charlie” supercells.northward and in “tail end charlie” supercells. Dropsonde JetDropsonde Jet

– Avoiding leading line convective cellsAvoiding leading line convective cells

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Airborne Doppler ScanningAirborne Doppler Scanning

ELDORA ~400 m

Pseudo-dual-Doppler Analysis: w from vertical divergence integration with w=0 @ echo top

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Optimal range for Doppler AnalysisOptimal range for Doppler Analysis

h R45¡45¡

R should be > h-RA

RA

Example:h~10 na mi. (50kft)RA ~ 5 na mi. (25kft)R ~ 5 na mi.

H ~ 10 na mi. (50kft)RA ~ 1 na mi. (5kft)R ~ 9 na mi.

To minimize vertical velocity contamination on radial winds need to keep scanning angles < 45°

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Squall Line Example - “Quad-Doppler”Squall Line Example - “Quad-Doppler”

NOAA P-3NOAA P-3

Example from TOGA COARE [Jorgensen et al. 1997]Example from TOGA COARE [Jorgensen et al. 1997]

NOAA P-3NOAA P-3

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NOAA P-3 Flight StrategiesNOAA P-3 Flight Strategies• Basic Doppler survey

module (twin legs) at 18,000 feet to facilitate switching to microphysics modules.

• Complete survey in 45 min or less

• Microphysics modules by NOAA P-3 will be attempted in suitable regions

• Attempt at least 2 legs ~70 km system relative separation (~38 na. mi). Doppler coverage overlap of ~10 km

• Where possible coordinate legs with NRL P-3

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System Relative TracksSystem Relative Tracksu=40 kntsSys Rel (u=0) u=20 knts

38 nm

u=60 knts

Line Speed(knots)

Cross leglength (n mi.)

(°)

0 38 0.010 35.8 2.420 34.3 4.830 32.7 7.240 31.2 9.650 29.6 12.060 28.0 14.4

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Microphysical Modules (NOAA P-3)Microphysical Modules (NOAA P-3) ~22 - 45 min flight pattern modules in well-~22 - 45 min flight pattern modules in well-

developed stratiform rain regionsdeveloped stratiform rain regions

• Lagrangian spirals

• Descent rate ~ 1 m/s above 0°C, ~ 5 m/s below

• Standard rate turn (~22° bank angle)

• Wind is allowed to advect aircraft

• Descend from ~-10°C (~6 km) through the melting level (~4 km) to as low as practical

• Requires ~22-45 minutes depending on vertical extent

• Perform several times

• As an alternative, could fly Doppler legs at different altitudes

• Either line parallel or line perpendicular oriented flight legs could be flown

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NOAA P-3 NOAA P-3 physics optionsphysics options

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Possible Flight Module SequencePossible Flight Module Sequence

42 min 33 min 45 min

~50 na mi

For 6 hour on-station time ~ 3 sequences of aboveFor 6 hour on-station time ~ 3 sequences of above

~2 hrs

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Flight Direction StrategiesFlight Direction Strategies Each aircraft has a Each aircraft has a Chief ScientistChief Scientist Ops DirectorOps Director and and NowcasterNowcaster at Ops Center at Ops Center Must have reliable sat com for information exchange Must have reliable sat com for information exchange

between these groupsbetween these groups

– Email messagesEmail messages

– ftp of gif imagesftp of gif images

– Voice (if necessary)Voice (if necessary) Ops Center to provide general guidance as to region to Ops Center to provide general guidance as to region to

investigate, including suggesting end points of flight legsinvestigate, including suggesting end points of flight legs Chief Scientists will fix flight legs to optimize best tracks Chief Scientists will fix flight legs to optimize best tracks

for objectivesfor objectives

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NOAA P-3 – Ops Center CommsNOAA P-3 – Ops Center CommsGlobal-Star, 9600 baud

PPP link,:ftp, e-mail

• Flight track guidance• Hourly nowcast & short-term

forecasts• Satellite & radar images

• Observation reports• Radar images

A

B

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Go/No Go Flight DecisionGo/No Go Flight Decision Proposal:Proposal:

– While at or above flight optimum flight While at or above flight optimum flight utilization curve flight decisions will be utilization curve flight decisions will be relatively conservative (i.e., aircraft launch will relatively conservative (i.e., aircraft launch will be predicated on observing be predicated on observing mesoscalemesoscale organization and behavior)organization and behavior)

Project Days20 May 6 July

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