Global Tropospheric Experiment Pacific Exploratory Mission-West A (GTE PEM West A) Langley ASDC Data Set Document

This document provides information on data products obtained during the GTE Pacific Exploratory Mission-West A atmospheric science expedition conducted over the western Pacific during September and October 1991. The objective of the mission was to investigate the atmospheric chemistry of ozone and sulfur over the northwestern Pacific. Measurements were made primarily by investigators' instruments located on the NASA Ames Research Center DC-8 airborne laboratory. Also provided are a list of principal investigators, a brief summary of measurement techniques and a list of publications.

This document provides information for the following PEM West A data set:

gte_pemtb_p3mXX.zip:	DC-8 Aircraft Data for flight XX
gte_pemwa_jpg_msn_04.zip:	Time series and altitude plots of in situ measurements on DC-8

gte_pemwa_ground_pc.zip:

Measurements of O3, CO, Hydrocarbons, SO2, and navigational data aboard the NIES aircraft during an intercomparison flights with the DC-8 aircraft

gte_pemwa_ground_ak.zip:	O3 concentration at Tsushima and Okinawa, Japan, and O3 and CO concentrations at Oki. Japan
gte_pemwa_ground_ja.zip:	Measurements of NO at Oki, Japan
gte_pemwa_ground_pr.zip:	High volume aerosols collection and anaysis of major ions and trace elements at Ken-Ting, Taiwan, Shemya, Alaska, Oaha, Hawaii, Midway Island, Okinawa, Japan, Hong Kong, and Cheju Island, Korea.
gte_pemwa_ground_ro.zip:	Measurements of HCs, NO, NOx, NOy, SO2, HNO3, NO3-, and SO4- at Lin An, Peoples Republic of China;
gte_pemwa_ground_zh.zip:	Measurements of NO NO2 NOx, SO2, NOy, and O3, Black Carbon at Lin An, Peoples Republic of China;

The investigators involved in the PEM West A mission were funded by NASA. The funded investigators, their organization and their grant, agreement, or contract were:

Investigator	Organization	Grant
Aircraft:
A. Bandy	Drexel U	NAG-1-1224
J. Bradshaw	GA Tech	NAG-1-1213
E. Browell	NASA Langley	N/A
G. Gregory	NASA Langley	N/A
B. Heikes	U of Rhode Island	NAG-1-1222
S. Rowland	U of California-Irvine	N/A
G. Sachse	NASA Langley	N/A
H. Singh	NASA Ames	N/A
R. Talbot	U of New Hampshire	NAG-1-1233
Ground:
R. Arimoto	U of Rhode Island	NAG-1-1225
J. Prospero	U of Miami	NAG-1-1229
Modeling:
J. Merrill	U of Rhode Island	NAG-1-1235
D. Davis	Georgia Tech	NCC-1-148
R. Newell	Mass Inst of Tech	NAG-1-1252
S. Liu	NOAA Boulder	N/A

Aircraft data sets are available for each investigation for each flight. Airborne measurements were made at generally constant altitude (i.e. "survey" flights) over the North Pacific Ocean and between major sites and multi-altitude flights (i.e. "intensive" flights) occurred around the intensive sites and closer to Asia. Flight missions were conducted during PEM West A from September 16 through October 22, 1991. Section 4.b lists the flight. The duration, altitude range, ascent and descent rate, and flight path for each mission varied depending on mission objectives and environmental conditions. Further information about the measurement region and time frame may be found in the Journal of Geophysical Research, Vol. 101, No. D1, 1641-1653, 20 January 1996.

This data set contains the DC-8 data submitted to the GTE data archive by the PEM West A investigators listed in Section 1.d. Included are the atmospheric chemistry, meteorological and navigational data recorded aboard the NASA DC-8 airborne laboratory. Japanese Cessna 404 aircraft flight 13 intercomparison data, ground site data, modeling products, trajectories and merged data sets are not contained in this archive. These data products can be found at the GTE data archive at http://www-gte.larc.nasa.gov/.

The atmospheric species and other parameters measured are listed in Hoell et al., [1996] Also listed for each are the name and affiliation of the principal investigator.

PEM West A investigators have individually reported the results of their investigations in the Journal of Geophysical Research, Vol. 101, No. D1, January 20, 1996. Also see Atmospheric Chemistry of the East Asian Northwest Pacific Region, Akimoto, H. et al., in The Global Atmospheric-Biospheric Chemistry, edited by R. G. Prinn, pp. 71-82, Plenum Press, New York, 1994 for related discussions.

There are data sets available from the Langley ASDC for the 13 other GTE missions conducted from 1983 to 2001. See the GTE home page at http://www-gte.larc.nasa.gov/ for a description of the available data.

Global Tropospheric Experiment Pacific Exploratory Mission West A (PEM West A)

If the person is known to be retired, deceased or no longer at the organization originally responsible for the investigation, it is noted and the contact information may be omitted. The contact information provided was current during the mission, but may no longer be current.

Alan R. Bandy
Drexel University
Department of Chemistry
32^nd and Chestnut Street
Philadelphia PA 19104
Telephone: 215-895-2640
Fax: 215-895-1980
E-mail: abandy@ac1.chemistry.drexel.edu

John D. Barrick
MS 483
NASA Langley Research Center
Hampton VA 23681-0001
Telephone: 757-864-5831
Fax: 757-864-5841
E-mail: j.d.barrick@larc.nasa.gov

John Bradshaw (Principal Investigator, Deceased)
Scott Sandholm (Co-Investigator)
Georgia Institute of Technology
Earth and Atmospheric Sciences
Baker Building, Room 107
923 Dalney Street
Atlanta GA 30332-0340
Telephone: 404-894-3895/3824
Fax: 404-894-5073
E-mail: ss27@prism.gatech.edu

Edward V. Browell
Mail Stop 401A
NASA Langley Research Center
Hampton VA 23681-0001
Telephone: 57-864-1273
Fax: 757-864-7790
E-mail: e.v.browell@larc.nasa.gov

Gerald L. Gregory (retired)
NASA Langley Research Center

Brian G. Heikes
University of Rhode Island
Graduate School of Oceanography
South Ferry Road
Narragansett RI 02882-1197
Telephone: 401-874-6810/6683
Fax: 401-874-6898
E-mail: zagar@notos.gso.uri.edu

Kenneth Kelly
NOAA Aeronomy Lab
325 Broadway
Boulder CO 80303
Telephone: 303-497-3355
Fax: 303-497-5373
E-mail: kellyk@al.noaa.gov

Yutaka Kondo
Nagoya University
Solar Terrestrial Environment Lab
3-13 Honohara
Toyokawa Aichi 442
Japan
Telephone: 81-5338-6-3154
Fax: 81-5338-6-0811
E-mail: kondo@stelab.nagoya-u.ac.jp

F. Sherwood Roland
University of California-Irvine
Department of Chemistry
Irvine, CA 92717
Telephone: 714-856-6016
Fax: 714-725-2905
E-mail: rowland@uci.edu

Glen W. Sachse
MS 472
NASA Langley Research Center
Hampton VA 23681-0001
Telephone: 757-864-1566
Fax: 757-864-8818
E-mail: g.w.sachse@larc.nasa.gov

Fumio Sakamaki
National Institute of Environmental Studies
Atmospheric Sciences Division
Onogawa 16-2 Tsukuba
Ibaraki 305
Japan
Telephone: 81-298-51-6111
Fax: 81-298-51-4732

Hanwant Singh
NASA Ames Research Center
Singh Group
Mail Stop 245-5
Moffett Field CA 94035
Telephone: 415-604-6769
Fax: 415-604-3265
E-mail: hb_singh@arc.nasa.gov

Robert W. Talbot
University of New Hampshire
Institute of Earth, Oceans, Space
Morse Hall
Complex Systems Research Center
Durham NH 03820
Telephone: 603-862-1546
Fax: 603-862-0188
E-mail: rwt@christa.unh.edu

Richard J. Blakeslee
NASA Marshall Space Flight Center
Earth Science and Applications Division
ES43
Huntsville AL 35812
Telephone: 205-544-1652
Fax: 205-544-5760
Hugh J. Christian
NASA Marshall Space Flight Center
Earth Science and Applications Division
ES43
Huntsville AL 35812
Telephone: 205-544-1649
Fax: 205-544-5760

Donald Blake
University of California-Irvine
Department of chemistry
Irvine CA 92717
Telephone: 714-856-4195
Fax: 714-725-2905
E-mail: dblake@orion.oac.uci.edu

Donald C. Thornton
Drexel University
Department of Chemistry
32^nd and Chestnut Street
Philadelphia PA 19104
Telephone: 215-895-2657
Fax: 215-895-1980
E-mail: dct@drexel.edu

Douglas D. Davis
Georgia Institute of Technology
School of Earth and Atmospheric Sciences
Room 108
221 Bobby Dodd Way
Atlanta GA 30332-0340
Telephone: 404-894-9565
Fax: 404-894-1993
E-mail: dd16@prism.gatech.edu

Shaw Liu (no longer at Georgia Tech)
Georgia Institute of Technology

Robert J. McNeal (retired)
NASA Headquarters

James M. Hoell, Jr. (retired)
NASA Langley Research Center

Reginald Newell (deceased 12/02)
Massachusetts Institute of Technology

Mark Shipham (no longer at NASA)
NASA Langley Research Center

Richard J. Bendura (retired)
NASA Langley Research Center

Leo DeGreef
NASA Ames Research Center
Mail Stop 211-12
Moffett Field, CA 94035
Telephone: 415-604-5342
Fax: 415-604-3885

Contact:
Airborne Science Program Office
MS D1623H
Edwards, CA 93523-0273
Phone: (661) 276-7453
Fax: (661) 276-3719
E-mail: airsci.program.coordinator@dfrc.nasa.gov

David P. Nicholas
ST Systems Corp.
28 Research Drive
Hampton VA 23666
Telephone: 757-865-7906
Fax: 757-865-0728

Jacqueline Johnson
ST Systems Corp.
28 Research Drive
Hampton VA 23666
Telephone: 757-865-7906
Fax: 757-865-0728

Leo DeGreef
(see prior listing)

Joseph W. Drewry (retired)
NASA Langley Research Center

Joseph W. Drewry (retired)
NASA Langley Research Center

Potential usage and applications of the described data sets can be seen in the articles that comprise the Journal of Geophysical Research PEM West A Special Section (Vol.101, No. D1 January 20, 1996), the 1992 AGU Western Pacific Geophysics Meeting, the 1993 Conference of the International Global Atmospheric Chemistry (IGAC) Project, and the 1994 Conference of the International Global Atmospheric Chemistry (IGAC) Project.

For convenience of the users, the calculated variables below are provided.

Mach Number, M:
	M = Mach Number Ps = Static Pressure Qc = Differential Pressure

True Air Speed, TAS:
	TAS = True Air Speed (knots) TS = Static Air Temperature (°K) M = Mach Number a = Speed of Sound

Static Air Temperature, Ts:
	TS = Static Air Temperature (°K) TT = Total Air Temperature (°K) γ = 1.4, ratio of specific heat of air at constant pressure and volume

Potential Temperature, θ:
	θ = Potential Temperature (°K) TS = Static Air Temperature (°K) Ps = Static Pressure (mb)

Vapor Pressure, e(mb):

e_water = 10^{[23.5518 - (2937.4/T)]} * T^(-4.9283)

e_ice = 10^{[11.4816 - (2705.2/T)]} * T^(-0.32286)

T = Static Air Temperature (°K) for Saturation Vapor Pressure
or
T = Dew/Frost Point (°K) for Partial Pressure of Water Vapor

Note:

StatTempDegK and ProjDP parameters recorded in the P-3B data set are substituted to calculate saturation vapor pressure and partial pressure of water vapor , respectively.

TSDEGC and ProjDP parameters recorded in the DC-8 data set are substituted to calculate saturation vapor pressure and partial pressure of water vapor, respectively. Also notice in the DC-8 data set there is a redundant static air temperature measurement, TSCALC, which is calculated by DADS. Although TSDEGC and TSCALC track closely they can diverge by ≈0.8° at the low and high ends of the measurement range.

Specific Humidity, q:

Relative Humidity, %:
w.r.t. water,	w.r.t. ice,

See the GTE Data Format Document at http://eosweb.larc.nasa.gov/guide/gte/gte_fmt.html

A general description of data granularity as it applies to the IMS appears in the EOSDIS Glossary. Aircraft data sets are available for each investigation for each flight

All DC-8 aircraft data for the mission are contained in the archive. No additional data products relevant to the PEM West A archive are anticipated.

This data is available online or on a CD-ROM via the LaRC ASDC at http://eosweb.larc.nasa.gov and from the GTE data archive at http://www-gte.larc.nasa.gov. Users may also order data by letter, telephone, and electronic mail from the ASDC.

Science, Users and Data Services Group
Atmospheric Science Data Center
MS 157D
Langley Research Center
Hampton, VA 23681 USA
Phone: 757-864-8656
Fax: 757-864-8807
E-mail: larc@eos.nasa.gov
Internet: http://eosweb.larc.nasa.gov

Publication of a portion(s) of the data archive should acknowledge the principal investigator(s) responsible for the data by referencing the appropriate manuscript in the Journal of Geophysical Research, Vol. 101, No. D1, January 20, 1996.

Airborne measurements were made over the western Pacific. A more detailed description of the surface level environmental characteristics for the experiment region is provided in the individual papers for each investigation included in the Journal of Geophysical Research, Vol.101, No. D1, January 20, 1996. Additional information may be found in other publications authored by the principal investigators or on the GTE homepage at http://www-gte.larc.nasa.gov/.

Flight missions were conducted during September and October, 1991. The duration, altitude range, ascent and descent rate, and flight path of each mission varied depending on mission objective and environmental (weather) conditions. The nominal air speed ranged from 480 knots (approximately 552 mph) at 12.6 km altitude to 240 knots (approximately 276 mph) at 0.34 km.

Data Set Name	Min Lat	Max Lat	Min Lon	Max Lon
Measurements aboard the DC-8 aircraft	0.4 N	60.8 N	175.3W	176.2E

Resolution varies for each measurement. See Hoell et al., [1996] for resolution of measurements made aboard aircraft.

No data gridding or binning of data to a geographic grid occurred during data processing.

Eighteen aircraft missions were conducted from September 16 to October 22, 1991.

Measurement Platform	Begin Date	End Date
DC-8 Aircraft	9/7/91	10/22/91

The sources of error vary widely depending on species and measurement environment and are addressed in the individual papers for each investigation included in the PEM West A special issue/section of the Journal of Geophysical Research, Vol.101, No. D1, January 20, 1996, and/or the papers referenced in that publication. For further details, contact the responsible principal investigators (see Section 1.d) and review the header for each data record. Instrument accuracy and precision, listed by parameter, can be found in Hoell et al., [1996].

1. Known Problems with the Data

   None reported for the current archive version. See the comment sections in the individual data files and the readme files submitted by the individual investigator.

2. Future Modifications and Plans

   The data sets submitted to the ASDC are considered final and no further updates are planned. However, modifications will be considered if requested by the investigators or otherwise justified.

Details of data acquisition and materials are addressed in the Journal of Geophysical Research PEM West A Special Section (Vol.101, No. D1 January 20, 1996), the 1992 AGU Western Pacific Geophysics Meeting, the 1993 Conference of the International Global Atmospheric Chemistry (IGAC) Project, and the 1994 Conference of the International Global Atmospheric Chemistry (IGAC) Project.

AGU Western Pacific Geophysics Meeting, Hong Kong, 17-21 August 1992.

Conference of the International Global Atmospheric Chemistry (IGAC) Project, Eilat, Israel, 18-22 April, 1993.

Second Conference of the International Global Atmospheric Chemistry (IGAC) Project, Fuji-Yoshida, Japan, 5-9 September 1994.

PEM West A Special Section, Journal of Geophysical Research, Vol.101, No. D1 January 20, 1996.

GTE Bibliography (http://www-gte.larc.nasa.gov/gte_pubs_update.htm)

Hoell, J. M., D. D. Davis, S. C. Liu, R. Newell, M. Shipman, H. Akimoto, R. J. McNeal, R. J. Bendura, and J. W. Drewry, Pacific Exploratory Mission-West A (PEM-West A): September-October 1991, J. Geophys. Res., Vol. 101, No. D1, 1641-1653, 20 January, 1996.

AGU - American Geophysical Union
ASDC - Atmospheric Science Data Center
CMDL - Climate Monitoring and Diagnostics Laboratory
DADS - Data Acquisition and Display System
EOSDIS - Earth Observing System Distributed Information System
GTE - Global Tropospheric Experiment
IGAC - International Global Atmospheric Chemistry
IMS - Information Management System
NASA - National Aeronautics and Space Administration
NIES - National Institute for Environment Science
NOAA - National Oceanic and Atmospheric Administration
PEM - Pacific Exploratory Mission
ProjDP - Project Dew Point
TSCALC - Static temperature, calculated by DADS
TSDEGC - Static temperature, measured directly, in Celsius

Creation Date:

November 2003

Revision Date:

Review Date:

Identification:

Curator:

Langley DAAC User and Data Services Office
Telephone: (757) 864-8656
FAX: (757) 864-8807
E-mail: larc@eos.nasa.gov

URL:

http://eosweb.larc.nasa.gov/GUIDE/dataset_documents/gte_pem_westa_dataset.html