Aircraft Data: Geographic Distribution, Acquisition, Quality Control, and Availability

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Aircraft Data Geographic Distribution,
Acquisition, Quality Control, and Availability

• Work at NOAA/ESRL/GSD and elsewhere

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AMDAR data -- definition

• AMDAR - Aircraft Meteorological DAta Relay
• The generic term for all automated meteorological
  reports from commercial aircraft
• GSD receives (from a variety of sources) and
  distributes (with restrictions) all AMDAR data
• Most AMDAR data are used in GSDs, and NCEPs
  weather models

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Flavors of AMDAR data

• MDCRS data (to be discussed by Al)
• E-AMDAR (Europe and Africa)
• AMDAR (Asia and Australia)
• Canadian (Canada, inc. flights into U.S.)
• TAMDAR (U. S. experimental)
• Other experimental

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MDCRS data (24 hours)
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E-AMDAR data
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AMDAR data (China, Japan, Australia, New
Zealand, So. Africa)
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Canadian data (jets and turboprops)
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TAMDAR data (turboprops, generally below 20 Kft)
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Experimental Turbulence (EDR) data, from UAL
(above 20Kft) and TAMDAR (problematic)
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Experimental Icing data from TAMDAR and
(sometimes) Delta
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Availability

• Real-time data are restricted to governments,
  researchers, etc.
• Graphical displays are available at
• http//amdar.noaa.gov/
• Binary and text data are available from MADIS
• http//madis.noaa.gov/
• data gt 48 h old are unrestricted
• archival data back to July 2001
• many tools for subsectioning data
• GSD is a research, not operational organization
• nonetheless, data flows have been pretty steady

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Data Restrictions

• Described at http//amdar.noaa.gov/FAQ.html
• Worked out over 15 years between NOAA and the
  participating US airlines
• Generally, non-commercial research users may have
  access to real-time data, if their work is of
  potential benefit to airlines

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AMDAR QC in the U.S.

• NCEP (Brad Ballish) is the official U.S. data
  quality center
• http//www.nco.ncep.noaa.gov/pmb/qap/
• GSD provides many research QC products based on
  the Rapid Update Cycle (RUC)
• Another U.S. center doing excellent work Pat
  Pauley at the Naval Research Laboratory
• Many non-U.S. centers also perform AMDAR QC

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AMDAR QC at GSD

• We look at differences between AMDAR observations
  and 1h forecasts from various versions of the RUC
  model

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The Rapid Update Cycle

• An hourly cycle
• Ingests all available data each hour
• AMDAR, TAMDAR, RAOBS (0 12 Z), Satellite,
  Surface, etc., etc.
• Covers the CONUS
• We run many RUC cycles
• For AMDAR QC, we use a 20 km cycle called dev2

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RUC - AMDAR Comparisons

• Statistical results are available at
  http//amdar.noaa.gov/ruc_acars/
• and include
• Time series for individual aircraft
• 3 and 7 day interactive statistics
• plan view of data and corresponding RUC values
• (summary statistics are open real-time data are
  restricted)

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http//amdar.noaa.gov/ruc_acars/
Plan view showing Wind-rejects for TAMDAR. Reject
reason indicated. Overall statistics shown
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(No Transcript)
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7-day summary statistics (sortable). New columns
show the fraction of obs rejected by the RUC, for
each variable. We reject many TAMDAR winds
because we dont accept descent winds currently
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Current AMDAR Data Quality

• Generally as good or better than RAOBs
• To check, we compare AMDAR and RAOBs with RUC 1h
  forecasts
• (RUC is not the truth, but, when a long time
  period is aggregated, can serve as a common
  denominator)
• Results to follow are from
• 1-31 Dec. 2006
• AMDAR data from 0 UTC /- 30 minutes
• 200 - 800 observations per pressure level
• Canadian jets and all turboprops excluded
• In the Great Lakes Region
• 13 RAOBs at 0 UTC

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AMDAR - dev2 1h fcst Temperature RMS difference
for obs taken near 0 UTC
Red shows AMDAR ascents and en-route Blue shows
AMDAR descents
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AMDAR - dev2 1h fcst Temperature RMS difference
for obs taken near 0 UTC AMDAR and RAOBs show
very similar statistics
Red shows AMDAR ascents and en-route Blue shows
AMDAR descents Green shows RAOB
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T bias is small (lt 0.5C) for AMDAR. (Generally
AMDAR ascents are warmer than descents, but not
at low levels during this winter month.)
Red shows AMDAR ascents and en-route Blue shows
AMDAR descents
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T bias is small (lt 0.5C) for AMDAR and
RAOBs. RUC shows a slight warm bias wrt RAOBs.
Red shows AMDAR ascents and en-route Blue shows
AMDAR descents Green shows RAOB
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For RMS of the vector wind difference with the
RUC
Red shows AMDAR ascents and en-route Blue shows
AMDAR descents
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For RMS of the vector wind difference with the
RUC, AMDAR and RAOB show similar values at all
levels.
Red shows AMDAR ascents and en-route Blue shows
AMDAR descents Green shows RAOB
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Water Vapor

• Most AMDAR measurements dont include vapor
  information
• WVSS-II measures it, but recent data is
  problematic
• TAMDAR measures it
• In lower troposphere only (below 500 mb, 18 Kft)
• In U. S. Midwest only
• Well look at recent TAMDAR results

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Relative Humidity RMS (wrt RUC dev2) for data
taken near 0 UTC
TAMDAR (open circles)
Red shows aircraft ascents and en-route Blue
shows aircraft descents
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Relative Humidity RMS (wrt RUC dev2) for data
taken near 0 UTC
TAMDAR (open circles) RAOBs (green) TAMDAR RH
differences with RUC are generally smaller than
RAOB RH differences. An encouraging result.
Red shows aircraft ascents and en-route Blue
shows aircraft descents
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Summary

• AMDAR is an extensive, accurate, and timely data
  source
• We thank the airlines for providing the data
• Tools at NCEP and GSD have been very helpful in
  evaluating
• Aircraft performance
• Model behavior
• Feedback to and from airlines, researchers, and
  other nations has been invaluable in improving
  quality.