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

This document provides information on data products obtained during the GTE ABLE 3B atmospheric science expedition conducted over northeastern Canada during July and August, 1990. The objective of the mission was to assess the importance of the Hudson Bay lowlands as a source of global methane. Measurements were made primarily by investigators' instruments located on the NASA WFF Electra airplane. Also provided are a list of principal investigators and a list of publications.

This document provides information for the following three data sets:

• GTE_A3B_Elec_Chem
• GTE_A3B_Elec_Flux [TAMMS aircraft data]
• GTE_A3B_Tower

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

Investigator	Organization	Grant
Aircraft:
John Barrick	NASA Langley	N/A
John Bradshaw	Georgia Tech	N/A
Edward Browell	NASA Langley	N/A
Gerald Gregory	NASA Langley	N/A
John Ritter	NASA Langley	N/A
Sherwood Rowland	U of California-Irvine	N/A
Glen Sachse	NASA Langley	N/A
Hanwant Singh	NASA Ames	N/A
Robert Talbot	U of New Hampshire	N/A
Surface:
David Fitzjarrald	State U of New York-Albany	N/A
Robert Talbot	U of New Hampshire	N/A
Steven Wofsy	Harvard	N/A
Mission Scientist:
Robert Harriss	U of New Hampshire	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 over northern Canada during transit flights (i.e. "survey" flights), and over multiple altitudes during flights closer to the intensive sites. Flight missions were conducted during ABLE 3B from July 6 through August 15 1990. 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 (weather) conditions. Ground-based measurements are discussed in Harriss et al., [1994]. 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. 99, No. D1, 1635-1643, January 20, 1994.

This data set contains all of the WFF Electra aircraft data and ground data collected from a tower in Schefferville, Ontario submitted to the GTE data archive by the ABLE 3B 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 a surface level site in Schefferville, Ontario. Isentropic back trajectories and merged data sets are not included in this archive. Those data can be found at the GTE data archive at http://www-gte.larc.nasa.gov/.

ABLE 3B investigators have individually reported the results of their investigations in the Journal of Geophysical Research, Vol. 99, No. D1, January 20, 1994.

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 the ASDC at http://eosweb.larc.nasa.gov/PRODOCS/gte/table_gte.html for a description of the available data.

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

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-mailk.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: 617-495-9837
E-mail: scw@io.harvard.edu

D. R. Fitzjarrald
Atmospheric Sciences Research Center
SUNY-Albany
100 Fuller Road
Albany NY 12005
Telephone: 518-437-8735
Fax: 518-442-3867
E-mail: fitz@asrc.cestm.albany.edu

R. W. Talbot
UNH
(See prior entry above)

P. M. Crill
UNH

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
UNC
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
UNH
Durham NH 03824
Telephone: 603-862-4725

Gary Whiting (no longer at LaRC)
STX, NASA LaRC

Ramona Travis
NASA Stennis
Building 1100, Code HA10
Stennis Space Center, MS 39520
Telephone: 601-688-1910

Walter. Glooschenko
Project Manager
CIRAC, York University
4700 Keele Street
North York, Ontario, Canada M3J 1P3

Leonard Barrie
Project Scientist
Atmospheric Environmental Service
4905 Dufferin Street
Downsview, Ontario Canada M3H 5T4
Telephone: 416-739-4868

W. Harley
Mission Coordinator
30 Winding Woods Crescent
London, Ontario Canada N6G 3G5
Telephone: 519-471-8441

Ian MacPherson
Aircraft Coordinator
National Research Council
Flight Research Laboratory
Building U-61
Montreal Road
Ottawa Ontario Canada K1A 0R6
Telephone: 613-998-3014

Bryan Misanchuk
Meteorologist
Atmospheric Environmental Service
4905 Dufferin Street
Downsview, Ontario Canada M3H 5T4
Telephone: 416-739-4872

H. Schiff
Mission Scientist
York University
Department of Chemistry
4700 Keele Street
North York, Ontario Canada M3J 1P3

G. Whiting
Project Manager
(See prior entry above)

McGill Station-Schefferville
T. Moore
Scientific Director Centre for Northern Studies and Research
McGill University
Burnside Hall
805 Sherbrook Street West
Montreal, QC Canada

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

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 NASA)
NASA Langley Research Center

Richard J. Bendura (retired)
NASA Langley Research Center

Roger Navarro (retired)
NASA Wallops Flight Facility

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 3B Special Section (Vol.99, No. D1 January 20, 1994), the 1991 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.

All of the WFF Electra aircraft and ground (tower) data for the ABLE 3 mission is contained in the archive. No additional data products relevant to ABLE 3 are anticipated. Isentropic back trajectories and merged data sets are not included in this archive. Those data can be found at the GTE data archive at http://www-gte.larc.nasa.gov/.

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 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

Airborne measurements were made over northern Canada. 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. 99, No. D1, January 20, 1994. 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/.

Fight missions were conducted during July and August 1990. 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 239 knots (approximately 275 mph) at 5.5 km altitude to 196 knots (approximately 226 mph) at 0.13 km.

Data Set Name	Min Lat	Max Lat	Min Lon	Max Lon
GTE_A3B_Elec_Chem	37.05N	63.75N	106.17W	49.40W
GTE_A3B_Elec_Flux	45.99N	58.78N	94.58W	60.21W
GTE_A3B_Tower*	55.00N	55.00N	67.00W	67.00W

Twenty-two aircraft missions were conducted from July 6 to August 15, 1990. Harris et al., [1994] shows dates and times for each mission. Ground site measurements at the Schefferville tower station were obtained from June 11 to August 17, 1990.

Data Set Name	Begin Date	End Date
GTE_A3B_Elec_Chem	7/6/90	8/15/90
GTE_A3B_Elec_Flux	7/11/90	8/11/90
GTE_A3B_Tower	6/11/90	8/17/90

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. 99, No. D1, January 20, 1994.

Parameter Source

The instruments used in making the measurements are listed in the individual papers included in the ABLE 3B Special Section in the Journal of Geophysical Research, Vol. 99, No. D1, January 20, 1994.

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. 99, No. D1, January 20, 1994.

Sample Data Record

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

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.

AGU Spring Meeting, Baltimore, MD, 28-31 May 1991.

ABLE 3B Special Section, Journal of Geophysical Research, Vol.99, No. D1 January 20, 1994.

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

Harriss, R. C., S. C. Wofsy, J. M. Hoell, , R. J. Bendura, J. W. Drewry, R. J. McNeal, D. Pierce, V. Rabine, and R. L. Snell, The Arctic Boundary Layer Expedition (ABLE 3B): July-August 1990, J. Geophys. Res., Vol. 99, No. D1, 1635-1643, 20 January, 1994.

ABLE 3A - Arctic Boundary Layer Expedition
AGU - American Geophysical Union
ASDC - Atmospheric Science Data Center
BREW - Biospheric Research of emissions from Wetlands
CIRAC - Canadian Institute for Research in Atmospheric Chemistry
CNWP - Canadian Northern Wetlands Project
DADS - Data Acquisition and Display System
EOSDIS - Earth Observing System Distributed Information System
GTE - Global Tropospheric Experiment
IMS - Information Management System
NASA - National Aeronautics and Space Administration
NOWES - Canadian Northern Wetlands Study
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_3b_dataset.html