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The Center for Meteorological Modeling conducts experimental and
theoretical studies designed to improve numerical modeling of the
atmosphere.
These research efforts received funds from NASA's
Atmospheric Effects of Aviation Project
(in the
Office of Aeronautics and Space Transportation Technology)
and the Global Modeling and Analysis Program in NASA's
Earth Science Enterprise.
Both projects gather existing meteorological data from aircraft
flight data recorders and attempt to make more effective use
of these data in meteorological models.
The primary current effort
is the Global Aircraft Data Set experiment.
(GADS; summary adapted from the original
1994 proposal).
It is an international collaboration involving participation and/or
funding from
NASA,
British Airways,
Singapore Airlines,
and some major weather services and research centers (
U.S.,
British,
Japanese,
and European ).
Meteorological information has been collected daily since
August 1995 from the flight data recorders of all (currently 56)
British Airways 747-400 aircraft and selected flights from
the Singapore Airlines fleet and transmitted to
SUNY Purchase.
The data is validated and sent to the world's major climate
and weather centers.
As of September 2007, the number of observations in data sparse
regions is approximately ACARS (97 Million), AMDAR (47 Million),
and GADS (57 Million). The ACARS and AMDAR totals do not include
redundant information over the data dense continental U. S. and
Europe. The GADS totals do not include another 350 Million 1 km
observations which are passively archived. Further information is
given in a
September 2007 report.
Web and Published Documentation
Typical distributions
(22 October 1999 and
01 September 2002)
and likely future
routes
can be compared with
operational reports
(set the type to "aircraft" and cycle through all four synoptic times
00, 06, 12, and 18 UTC)
to compare with the full day of GADS observations.
The broad context of the role of aircraft observations was
described in a 2004
historical review
published in the World Meteorological Organziation (WMO)
Bulletin.
Early versions of the results
are given in color images showing
discrepancies
between aircraft data and 1992 analyses.
[J. Tenenbaum, "Jet stream wind analyses: comparisons with
independent aircraft data over Southwest Asia."
Wea. and Forecasting, 6,
320-326 (1991).]
More recent results are in the following papers,
J. Tenenbaum,
"Jet Stream Winds: Comparisons of Aircraft
Observations with Analyses."
Wea. and Forecasting, 11,
188-197 (1996).
L. Rukhovets, J. Tenenbaum, and M. Geller,
"The Impact of Additional Aircraft Data on the Goddard Earth
Observing System Analyses."
Mon. Wea. Rev., 126,
2927-2941 (1998).
G. J. Rickard, R. W. Lunnon, and J. Tenenbaum,
"The Met Office upper air winds: Prediction and verification in
the context of commercial aviation data."
Meteorol. Appl., 8,
351-360 (2001).
C. Cardinali, L. Rukhovets, and J. Tenenbaum,
"Jet Stream Analysis and Forecast Errors Using GADS Aircraft
Observations in the DAO, ECMWF, and NCEP Models."
Mon. Wea. Rev., 132,
764-779 (2004).
conference proceedings,
J. Tenenbaum and L. Rukhovets,
"Determining Biases in Hadley Circulation Reanalyses Using Independent Aircraft Observations".
Extended abstract. Proceedings of the Third WCRP International Conference on Reanalysis, January 28 - February 1, 2008, Tokyo, Japan.
and are used in
C. Cardinali, L. Isaksen, and E. Andersson.
"Use and impact of automated aircraft data in a global 4DVAR
data assimilation system".
Mon. Wea. Rev., 131, 1865-1877 (2003).
A primary goal of the research is specifically to estimate and
decrease the biases of the NASA
Global Modeling and Assimilation Office
analyses.
These analyses are used in support of the
Terra
(nee EOS-AM; MODIS and MOPITT instruments) and
Aqua
(nee EOS-PM; AIRS and MODIS instruments) earth observing satellites.
Current Work and Future Plans
The problems illustrated in the
Rukhovets et al. (1998) paper are still present in current
assimilation systems.
A case study of a 1998 problem case is shown in a brief
report.
Additional problems are illustrated by the extreme situations
present in conjuction with the 1999
Christmas storms.
over northern France and southern England
and a poorly analyzed jet stream
case
over Alberta, Canada.
The primary value of the GADS observations is that they can provide
substantial additional information relative to information available
in real-time on the meteorological Global Telecommunications System (GTS).
These can be incorporated in the Goddard GMAO late-look
(approximately 15 days after the observation time) analyses.
The status of these analyses can be examined by following links from the
GMAO
home pages.
Most of the discussion dealing with the first-look (near real-time)
analyses also applies to the late-look analyses.
Current work includes
[Copies of referenced papers including all figures are
available by e-mail request from
cmm@jet.purchase.edu
]
(maintained by Marge Oztunali
)
marge@jet.purchase.edu
(last updated 17 April 2008)
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