Global Tropospheric Experiment Arctic Boundary Layer Expedition 3A (ABLE 3A) Langley ASDC Document Data Set Document

This document provides information on data products obtained during the GTE ABLE 3A atmospheric science expedition conducted over northern Canada and Alaska during July and August 1988. The objectives of the mission were to investigate the magnitude and variability of methane emissions from the tundra ecosystem, and to elucidate factors controlling ozone production and destruction in the Arctic atmosphere. Measurements were made primarily by investigators' instruments located on the NASA Wallops Electra airborne laboratory. Also provided are a list of principal investigators and a list of publications.

This document provides information for the following four data sets:

• GTE_A3A_Elec_Chem
• GTE_A3A_Elec_Flux
• GTE_A3A_Tower
• GTE_A3A_Met_Traj

The investigators involved in the ABLE 3A mission were funded by NASA. The funded investigators, their organization and their grant, agreement or contract number were:

Investigator	Organization	Grant
Aircraft:
D. D. Davis	Georgia Tech	N/A
Edward Browell	NASA Langley	N/A
Gerald Gregory	NASA Langley	N/A
Sherwood Rowland	U of California-Irvine	NAG-1-783
Glen Sachse	NASA Langley	N/A
Hanwant Singh	NASA Ames	N/A
R. C. Harriss	U of New Hampshire	NAG-1-1014
Surface:
David Fitzjarrald	State U of New York-Albany	N/A
R. C. Harriss	U of New Hampshire	NAG-1-1014
Steven Wofsy	Harvard	N/A

Aircraft data sets are available for each investigation for each flight. Ground-based data are usually available on a daily basis. Airborne measurements were typically obtained at constant altitude during the transit flights (i.e. "survey" flights), and over multiple altitudes during flights from the intensive sites. Flight missions were conducted during ABLE 3A from July through August 1988. Section 4.b lists the flight dates. The duration, altitude range, ascent and descent rate, and flight path for each mission varied depending on mission objectives and environmental conditions. Ground-based measurements are discussed in Harriss et al., [1992]. The automated ground sites provided daily measurements during the time frame when airborne measurements were being made and weekly averaged samples before and after. Further information about the measurement region and time frame may be found in the Journal of Geophysical Research, Vol. 97, No. D15, 16383-16394, October 30, 1992.

This data set contains all of Electra aircraft data, trajectory and ground station data submitted to the GTE data archive by the ABLE 3A investigators listed in Section 1.d. Included are the atmospheric chemistry, meteorological and navigational data recorded aboard the NASA Wallops Electra airborne laboratory and data obtained from surface level sites. Merged data sets are not included in this archive but 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 Section 4.c. Also listed for each are the name and affiliation of the principal investigator.

ABLE 3A investigators have individually reported the results of their investigations in the Journal of Geophysical Research, Vol. 97, No. D15, October 30, 1992.

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

Global Tropospheric Experiment Arctic Boundary Layer Expedition 3A (ABLE 3A)

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: 757-864-1273
Fax: 757-864-7790
E-mail: e.v.browell@larc.nasa.gov

Gerald L. Gregory (retired)
NASA Langley Research Center

E. B. Pereira
Instituto de Pesquisas Espaciais
C.P. 515
12200-Sao Jose dos Campos - SP
Brazil
Telephone: 55-123-229977
Fax: 55-123-218743

John Ritter (no longer at LaRC)
Kenneth Lee Thornhill (Current)
MS 483
NASA Langley Research Center
Hampton VA 23681-0001
Telephone: 757-864-5169
Fax: 757-864-5841
E-mail: k.l.thornhill@larc.nasa.gov

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

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

S. C. Wofsy
Center for Earth and Planetary Physics
Pierce Hall
29 Oxford Street
Harvard University
Cambridge MA 02138
Telephone: 617-495-4566
Fax: 617-495-2768
E-mail: scw@io.harvard.edu

D. R. Fitzjarrald
Atmospheric Sciences Research Center
SUNY-Albany
100 Fuller Road
Albany NY 12005
Telephone: 518-442-3838
Fax: 518-442-3867

P. Kebabian
Center for Chemical and Environmental Physics
Aerodyne Research, Inc.
Billerica MA 01821
Telephone: 617-663-9500

S. C. Wofsy
(See above entry)

Vic Klemas
College of Marine Studies
U DE
Newark DE 19716
Telephone: 302-451-2336

Chris Martens
Marine Sciences
CB-3300, 12-5 Venable Hall
U NC
Chapel Hill, NC 27599-3300
Telephone: 919-962-1255

John Dacey
Woods Hole Oceanographic Institute
Woods Hole MA 02543
Telephone: 617-548-1400, ext. 2327

Gary King
Darling Marine Center
U ME
Walpole ME 04573
Telephone: 207-563-3146

Mark Hines
Institute for Study of Earth, Oceans and Space
U NH
Durham NH 03824
Telephone: 603-862-4725

D. S. Bartlett (no longer at NASA LaRC)
NASA Langley Research Center

R. C. Harriss (no longer at NASA LaRC)
NASA Langley Research Center

D. 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

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

R. C. Harriss
Institute for the Study of Earth, Oceans and Space
Science and Engineering Research Center
University of New Hampshire
929 College Road
Durham NH
Telephone: 603-862-3875

R. C. Harriss
(See prior listing above)

and S. C. Wofsy
(See prior listing above)

Robert J. McNeal (retired)
NASA Headquarters

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

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

Richard J. Bendura (retired)
NASA Langley Research Center

Roger Navarro (retired)
NASA Wallops

Or Contact:
Wallops Flight Facility Aircraft Office
NASA Wallops Flight Facility
Wallops Island VA 23337-5099
Telephone: 757-824-1529

Helen Ann Thompson (no longer at ST Systems)

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 ABLE 3A Special Section (Vol. 97, No. D15 October 30, 1992) and the 1989 Spring AGU Meeting.

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

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

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

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

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

Vapor Pressure, e :

e_water (mb) = [1.0007 + (3.46 * 10^-6 * P_S)] * 6.1121* EXP[17.502 * T/(240.97 + T)]

e_ice (mb) = [1.0003 + (4.18 * 10^-6 * P_S)] * 6.1115* EXP[22.452 * T/(272.55 + T)]

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

Note:

1. ProjDP of zero or greater should be used to derive the partial pressure of water vapor w.r.t water (e_water ) and the ProjDP less than zero should be used to derive the partial pressure of water vapor w.r.t ice (e_ice).

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

3. 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 ≈ 1° at the low and high ends of the measurement range.

Specific Humidity, q:
Mixing Ratio, r:
Note: ppmv = 1.608 * ppmw ppmw = 0.622 * ppmv

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

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. Surface level data are available on a daily basis.

This data set contains all of Electra aircraft data, trajectory and ground station data submitted to the GTE data archive by the ABLE 3A investigators listed in Section 1.d. Included are the atmospheric chemistry, meteorological and navigational data recorded aboard the NASA Wallops Electra airborne laboratory and data obtained from surface level sites. Merged data sets are not included in this archive but can be found at the GTE data archive at http://www-gte.larc.nasa.gov/. No additional data products relevant to ABLE 3A are anticipated.

This data is available online or on a CDROM 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 (see 3e) from the ASDC.

The Atmospheric Science Data Center at NASA's Langley Research Center.

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

Airborne measurements were made over northern Canada and Alaska. 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. 97, No. D15, October 30, 1992. 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 July and August, 1988. Also shown are the takeoff and landing sites. The duration, altitude range, assent and descent rate, and flight path of each mission varied depending on mission objective and environmental conditions. The nominal air speed ranged from 275 knots (approximately 316 mph) at 6.13 km altitude to 197 knots (approximately 227 mph) at 0.123 km.

Data Set Name	Min Lat	Max Lat	Min Lon	Max Lon
GTE_A3A_Elec_Chem	38.0N	80.9N	-75.5E	-168.0E
GTE_A3A_Elec_Flux	60.4N	70.5N	-154.8E	-164.2E
GTE_A3A_Tower	61.0N	61.0N	162.5W	162.5W
GTE_A3A_Met_Traj	38.0N	80.9N	-75.5E	-168.0E

ABLE 3A aircraft missions were conducted from July 7 through August 17, 1988. The dates and times for each mission are given in Harriss et al., [1992]. Ground site measurements were obtained from (date) to (date).

Data Set Name	Begin Date	End Date
GTE_A3A_Elec_Chem	7/7/88	8/17/88
GTE_A3A_Elec_Flux	7/18/88	8/9/88
GTE_A3A_Tower	7/10/88	8/13/88
GTE_A3A_Met_Traj	7/5/88	8/17/88

Not all of the parameters are in each data set granule. Also, the ranges vary between data sets and between granules within each data set. Species measured are given in Harriss et al., [1992]

Parameter Description

The variables measured are standard atmospheric chemical and meteorological species requiring no further elaboration here.

Unit of Measurement

The units of measure vary widely depending on species and measurement environment and are addressed in the individual papers for each investigation included in the Journal of Geophysical Research, Vol. 97, No. D15, October 30, 1988.

Parameter Source

The instruments used in making the measurements are listed in the individual papers included in the ABLE 3A Special Section in the Journal of Geophysical Research, Vol. 97, No. D15, October 30, 1992.

Parameter Range

The ranges of data vary widely depending on species and measurement environment and are addressed in the individual papers for each investigation included in the Journal of Geophysical Research, Vol. 97, No. D15, October 30, 1992.

Sample Data Record

The GTE Data Format Document (http://eosweb.larc.nasa.gov/guide/gte/gte_fmt.html) contains examples of each data set type.

The sources of error vary depending on species and measurement environment and are addressed in the papers included in the ABLE 3A special issue of the Journal of Geophysical Research, Vol. 97, No. D15, October 30, 1992, and/or papers referenced in that publication and readme files and/or header records associated with each data file.

1. Known Problems with the Data

   None reported for the current archive version. See the readme files and header records included with each data set for information provided by the responsible 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 ABLE 3A Special Section (Vol.97, No. D15, October 30, 1992) and the 1989 AGU Spring Meeting.

AGU Spring Meeting, Baltimore, MD, 7-12 May 1989.

ABLE 3A Special Section, Journal of Geophysical Research, Vol. 97, No. D15, October 30, 1992.

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

Harriss, R. C., S. C. Wofsy, D. S. Bartlett, M. C. Shipham, D. J. Jacob, J. M. Hoell, , R. J. Bendura, J. W. Drewry, R. J. McNeal, R. L. Navarro, R. N. Gidge, and V. E. Rabine,, The Arctic Boundary Layer Expedition (ABLE 3A): July-August 1988, J. Geophys. Res., Vol. 97, No. D15, 16383-16394, 30 October, 1992.

ABLE 3A - Arctic Boundary Layer Expedition
AGU - American Geophysical Union
ASDC - Atmospheric Science Data Center
BREW - Biospheric Research of emissions from Wetlands
DADS - Data Acquisition and Display System
EOSDIS - Earth Observing System Distributed Information System
GTE - Global Tropospheric Experiment
IMS - Information Management System
LaRC - NASA Langley Research Center
NASA - National Aeronautics and Space Administration
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_able_3a_dataset.html