Turbulence Diagnoses and Forecasts

1
Turbulence Diagnoses and Forecasts

• Bob Sharman
• NCAR/RAL
• Weather in the Cockpit Workshop
• 8 August 2006

2
FAA AWRP Turbulence PDT work areas

• Develop/implement in situ turbulence observations
• UAL, SWA, Delta
• Develop/implement remotely sensed turbulence
  observations
• NEXRAD Turbulence Detection Algorithm (NTDA)
• Develop turbulence nowcasting and forecasting
  systems
• Graphical Turbulence Guidance (GTG)
• GTGN
• All products can be uplinked to the cockpit

3
In situ turbulence measurement and reporting
program

• Goal To augment/replace subjective PIREPs with
  objective and precise turbulence measurements
• Features
• Automatically computes
• atmospheric turbulence intensities
• Aircraft independent (eddy dissipation rate, EDR)
• Automatically downloads data periodically during
  flight using ACARS network
• Can convert EDR to aircraft loads and vice versa
  given information about aircraft
• Adopted as ICAO Standard

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UAL in-situ compared to pireps
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NEXRAD in-cloud turbulence detection algorithm
(NTDA)
Graphic courtesy of virtualskies.arc.nasa.gov
Cockpit display or radioed alert
Dispatch, ATC, etc.
TPAWS
EDR
In-cloud edr display
NEXRAD or TDWR
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NTDA status
EXP TURB FI UAL -- 20 Oct 2005
220857Z FL 360 orient. 95 deg 'X'aircraft,
''waypoint, ''route ' 'no_data, 'o'smooth,
'l'light 'M'mod, 'S'severe ---------(36nm to
COWES)--------------- llll
lMMMMMMll 112nm lll llllMMMMlll
llMMMMMMMMl 108nm llMMMlMMMMM
llMMMlllMM 104nm lMMllll
Mll 100nm ll ll
ol lll 096nm lllllllllllll
llllllllllllll 092nm llllllllllllll
l llllllllll lll llllllll 088nm
lllllMllMMllll lllllllll lllMMMMMMll
lllllllllll 084nm llllMMMMMMM
llllllllllllll lllllMMMMMMl
llllllllllllllll 080nm llllllMMMMM
llllllllllllllll llllMMlMMM
llllllllllllllll 076nm ollMMMlll l
llllllllllllllll ollMMMllllllMllll
lllllll STL llllllllllMMllll lllllll
ll lll Mlllll llllll 068nm
ll llllllMMlllllM llllll lll
lllllllllllMM llllll 064nm lll
llllllllllMM llllll l ll
lllllllllMMM lllMll 060nm lll
llllllllllMMMM lllMMMl ll
lllllllMMlMM MMllMMMM 056nm Ml
llllllMMlMM MlMMMMMM M l
llllllMMlMMl MMMMMMMMM 052nm l
lllllllllllMMlllMMMMMMMMMMM lll
lllllllllllMMMllMMMMMMMMMMMM 048nm lll lll
ollllllMMMllMMMSSMMMMMMM llM
llloollllllllllllMMSSMMMMMMM 044nm
llMMMlllollllllllllllMMMSSMMMMMM llMMM
llll lllllllllMMMMMMMlMMM 040nm M
llllllllllllllllMMMMMllMMM
lllMMlllllllllllllMMMlllllM 036nm MMllMMll
llllllllllllllllM MMMlMMll
llllllllllllll 032nm MMMllllll ooll lll
llll MMMllllllloll l 028nm
MMMllllllMMl lMMlll MMl 024nm
M M M 020nm
MMll Mlllll
MMM WELTS llll llMMM
lll llMMM 012nm ll
llMM 008nm
004nm
valid
----------------X---------------- 2205Z -40nm
(39.0N, 92.1W) 40nm

• Ongoing verification against in situ data
• Web-based display of NTDA product
• Successful demonstration last summer of NTDA text
  graphic uplink to selected UAL aircraft with
  character printer

severe
NTDA edr contours
In situ edr tracks
SFO-BWI 20 Oct 05
7
/EXPERIMENTAL TURBULENCE FI UAL/AN NUA
UPLINK -- 01 Jul 2006 220810Z FL 360 orient.
88 deg ''waypoint, ''route, 'X'aircraft at
43.2N, 86.3W ' 'no_data, 'o'smooth, 'l'light,
'M'mod, 'S'severe ---------------------------(25
to EJOYS)------------------ ll
lll
lll lll
lll
lll lllll lll l
ollll lll M
oollll lll llll
lll MONEE llllllll lll l
ll llllll lll l llll
lllllllll lll l oll
lllllllllll lll l ool lllllllll
lll lllllll lll
llllll lll l
llllllll lll l olllllllll
lll l ooo lllllll Mll
o lllllll lll
lllll lll lloo lol
llo
llo lll
lll l
ll lll l lll
lll l GRUBB lll lll 040
ll ll












----------------valid----------X
------------------------- -90 90Left 40 2205Z
(86 from BAE) Right 40
NTDA turbulence display at 2210 UTC
Radar at 2215 UTC (deviation began at 2213)
View toward left at about 2215 UTC

• NTDA uplink message at 2208 UTC

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TPDT forecasting

• Graphical Turbulence Guidance (GTG) forecast
  product
• Combines many turbulence indicators
  observations
• Rapid updates
• 4D gridded output
• ADDS displays
• GTG2 early 2007
• GTG3 early 2010

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Turbulence nowcasting - GTGN
GTG 0-1 hr forecast
Real-time pireps
Lightning
Real-time in situ data
NTDA
Real-time ACARS winds/temp
Wind profilers
3D data cube of observed/inferred turbulence
updated every few minutes
Satellite features
Metars
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Global GTG (TFO)

• Uses NOAAs GFS model
• Diagnoses and forecasts of CAT gt FL200
• Experimental product should be available by early
  2008
• Example
• Upper RUC20
• Lower GFS

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07/06/2005 CIT (gtFL200 in situ)
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Summary

• Enhanced situational awareness for tactical
  decisions about turbulence avoidance can be
  provided through uplinks to the cockpit
• In situ pireps
• NTDA AVAILABLE NOW!
• GTG
• GTGN ( 5-10 min update)
• In-flight strategic planning can use GTG or TFO
• Updated consistent with WRF, GFS forecast cycles
• Probabilistic forecasts

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• Demos