Global Tropospheric Experiment Amazon Boundary Layer Expedition 2A (ABLE 2A) Langley ASDC Document Data Set Document

This document provides information on data products obtained during the GTE ABLE 2A atmospheric science expedition conducted over the Amazon during July and August 1985. The objective of the mission was to characterize the chemistry and dynamics of the lower atmosphere over the Amazon Basin during the early-to-middle dry season. Measurements were made primarily by investigators' instruments located on the NASA Wallops Electra 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 five data sets:

• gte_able2a_aircraft_msn_02.zip - ABLE 2A Electra Aircraft Data
• gte_able2a_ground.zip - ABLE 2A Ground Data

NASA funded the investigators involved in the ABLE 2A mission.
The funded investigators, their organization and their grant, agreement or contract numbers were:

Investigator	Organization	Grant
Aircraft:
M. O. Andreae	Florida State U	NAG-1-588
S. M. Beck	NASA Langley	N/A
Edward Browell	NASA Langley	N/A
M. Garstang	U of Virginia	NCC-1-95
Gerald Gregory	NASA Langley	N/A
R. A. Rasmussen	Oregon Grad Ctr	NAG-1-589
Glen Sachse	NASA Langley	N/A
R. W. Talbot	Bionetics Corp	NAS-1-16978
A. L. Torres	NASA Wallops	N/A
S. C. Wofsy	Harvard U	NAG-1-55
Surface:
David Fitzjarrald	State U of New York-Albany	NAG-1-583
R. C. Harriss	NASA Langley	N/A
C. L. Martin	Simpson Weather Assoc	N/A
D.I. Sebacher	NASA Langley	N/A
Steven Wofsy	Harvard U	NAG-1-55
P. R. Zimmerman	NCAR	N/A
AGE:
R. C. Harriss	NASA Langley	N/A
P. A. Matson	NASA Ames	N/A
J. M. Melack	U of California-Santa Barbara	NCC-1-82
J. E. Richey	U of Washington	NAGW-711
P. Vitousek	Stanford U	N/A
Satellite:
S. T. Shipley	NASA Langley	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 transit flights (i.e. "survey" flights), and over multiple altitudes closer flights from the intensive sites. Flight missions were conducted during ABLE 2A from July through August 1985. 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 (weather) conditions. 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. 93, No. D2, February 20, 1988.

This data set contains all of the data submitted to the GTE data archive by the ABLE 2A investigators listed in Section 1.d. Included are the atmospheric chemistry, meteorological and navigational data recorded aboard the NASA Wallops Electra airborne laboratory, data obtained from surface level sites, sonde and balloon data and all of the merged data sets. Note that the ASDC data link points the user to the GTE data archive to obtain the data.

The atmospheric species and other parameters measured are listed in Section 4.c and in Harriss et al., [1988]. Also listed for each are the name and affiliation of the principal investigator.

ABLE 2A investigators have individually reported the results of their investigations in the Journal of Geophysical Research, Vol. 93, No. D2, February 20, 1988.

There are data sets available from the Langley ASDC for 13 other GTE missions conducted from 1983 to 2001. See the GTE home page and/or the ASDC GTE Data Table for a description of the available data.

Global Tropospheric Experiment Amazon Boundary Layer Expedition 2A (ABLE 2A)

If the person is known to be retired, deceased or no longer at the organization originally responsible for the experiment, 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.

M. O. Andreae (no longer at FSU)
Florida State University
Department of Oceanography
Tallahassee FL 32306
Telephone: 904-644-1221

S. M. Beck (no longer at NASA LaRC)
NASA Langley Research Center

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

R. A. Rasmussen
Oregon Graduate Center
Department of Environmental Science
19600 N. W. Walker Road
Beverton OR 97006-1999
Telephone: 503-645-1121
E-mail: rrasmus@ese.ogi.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

A. W. Setzer
INPE
Department of Meteorology
C.P. 515
12.200 - San Jose dos Campos - SP
Brazil
Telephone: 55-123-229977

Robert W. Talbot (now at UNH)
Bionetics Corp.

B. L. Torres (retired)
NASA Wallops

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

E. M. C. Cutrim
Federal University of Para
Department of Meteorology
Centro de Geociencias
66000 Belem, Para Brazil
Telephone: 11-55-91-226-181
E-mail: elen.cutrim@wmich.edu

P. L. S. Dias
Department of Meteorology
Instituto Astronomico e Geofisico (IAG)
University de Sao Paulo
Caixa Postal 306ZF
01000 Sao Paulo, SP Brazil
Telephone: 55-11-212-3037

D. R. Fitzjarrald
Atmospheric Sciences Research Center
SUNY-Albany
100 Fuller Road
Albany NY 12005
Telephone: 518-442-3838
Fax: 518-442-3867
E-mail: fitz@asrc.cestm.albany.edu

M. Garstang
University of Virginia
Department of Environmental Sciences
Clark Hall
Charlottesville VA 22903
Telephone: 804-979-3571
Fax: 804-977-3733
E-mail: mxg@thunder.swa.com

V. W. J. H. Kirchhoff
Instituto Nacional de Pesquisas Espaciais
C. P. 515
12201 Sao Jose dos Campos
Sao Paulo, Brazil
Telephone: (55) 123-41-8977
Fax: (55) 123-21-8743

J. M. Melack
University of California – Santa Barbara
Telephone: 805-893-3879
E-mail: melack@lifesci.ucsb.edu

L. C. B. Molion
INPE
Department of Meteorology
C.P. 515
12.200 - Sao Jose Dos Campos - SP
Brazil

L. M. Moreira-Nordemann
INPE

P. Artaxo Netto
University of Sao Paulo
Instituto de Fisica
Caixa Postal 66318
CEP 05389-970, Sao Paulo SP Brazil
Telephone: 55-11-818-7016
Fax: 55-11-818-6749

C.A. Nobre
INPE

H. S. Pinheiro
Federal University of Para

D.I. Seabacher (no longer at NASA LaRC)
NASA Langley Research Center

A.W. Setzer
INPE
Department of Meteorologia
C.P. 515, 12.200
Sao Jose Dos Campos
Sao Paulo Brazil
Telephone: 011-55-123-22-9977

S. C. Wofsy
(See above prior entry)

P. A. Zimmerman
NCAR
P. O. Box 3000
Boulder CO 80307
Telephone: 303-497-1406
E-mail: zimmer@ucar.edu

J. E. Richey
University of Washington
College of Ocean and Fishery Sciences
Seattle WA 98195
E-mail: jrichey@u.washington.edu

P. Vitousek
Stanford University
HERRIN LABS RM 498A
Mail Code 5020
Stanford, California, 94305-5020
Telephone: 650) 725-1866
Fax: (650) 725-1856
E-mail: vitousek@stanford.edu

R. C. Harriss
(See prior above listing)

R. C. Harriss
(See prior listing above)

S. C. Wofsy
(See prior listing above)

A. G. Motta
Coordenadoria Adjunta Natal/Fortaleza
INPE
Av. Salagado Filhno No 3000
Brazil

L. C. B. Molion
(See prior above listing)

Robert J. McNeal (retired)
NASA Headquarters

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

M. Garstang
(See prior above listing)

Richard J. Bendura (retired)
NASA Langley Research Center

S. M. Beck
(See prior above listing)

R. L. Navarro (retired)
NASA Wallops

H. A. Thompson (no longer at Bionetics Corp.)
Bionetics Corp.

D. S. McDougal (retired)

R. C. Harriss
(See prior above listing)

Potential usage and applications of the described data sets can be seen in the articles that comprise the Journal of Geophysical Research ABLE 2A Special Section (Vol. 93, No. D2 February 20, 1988) and the 1986 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,

See the GTE Data Format Document

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 data available for the ABLE 2A mission are listed in the ABLE 2A Data Table. No additional data products relevant to ABLE 2A are anticipated.

The ABLE 2A data are available online through the GTE Data Archive or on a CDROM which can be ordered online throught the LaRC 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

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. 93, No.D2, February 20, 1988.

Airborne measurements were made over the Amazon, as indicated in figure 3. 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. 93, No. D2, February 20, 1988. Additional information may be found in other publications authored by the principal investigators or on the GTE home page.

Flight missions were conducted during July through August 1988. The duration, altitude range, ascent and descent rate, and flight path of each mission varied depending on mission objective and environmental conditions. The nominal air speed ranged from 290 knots (approximately 334 mph) at 5.66 km altitude to 206 knots (approximately 237 mph) at 0.14 km.

Measurement Platform	Min Lat	Max Lat	Min Lon	Max Lon
Electra Aircraft	7.20S	37.10N	47.48W	76.30W
Ground sites	2.95S	3.15S	59.95W	59.98W
Sondes	2.95S	2.95S	59.95W	59.95W
Tethered Balloons	2.95S	2.95S	59.95W	59.95W
Merged Data	7.20S	37.10N	47.48W	76.30W

Resolution varies for each measurement. See the individual headers associated with each data file for specific information.

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

ABLE 2A aircraft missions were conducted from July 11 through August 13, 1988.

Measurement Platform	Begin Date	End Date
Electra Aircraft	7/11/85	8/13/85
Ground Site	7/14/85	8/10/85
Sondes	7/15/85	8/5/85
Tethered Balloon	7/20/85	8/5/85
Merged Data	7/11/85	7/11/85

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., [1988].

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. 93, No. D2, February 20, 1988.

Parameter Source

The instruments used in making the measurements are listed in the individual papers for each investigation included in the Journal of Geophysical Research, Vol. 93, No. D2, February 20, 1988.

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. 93, No. D2, February 20, 1988.

Sample Data Record

The GTE Data Format Document 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 2A special issue of the Journal of Geophysical Research, Vol. 93, No. D2, February 20, 1988, 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 2A Special Section (Vol. 93, No. D2, February 20, 1988) and the 1986 AGU Spring Meeting.

1. AGU Spring Meeting, Baltimore, MD, 19-22 May 1986.

2. ABLE 2A Special Section, Journal of Geophysical Research, Vol. 93, No. D2, February 20, 1988.

3. GTE Bibliography

4. Harriss, R. C., S. C. Wofsy, M. Garstang, E. V. Browell, L. C. B. Molion, R. J. McNeal, J. M. Hoell, R. J. Bendura, S. M. Beck, R. L. Navarro, J. T. Riley, and R. L. Snell, The Amazon Boundary Layer Experiment (ABLE 2A): Dry Season 1985, J. Geophys. Res., Vol. 93, No. D2, 1351-1360, 20 February 1988.

EOSDIS Acronyms | EOSDIS Glossary.

ABLE 2A - Amazon Boundary Layer Expedition - Dry Season
AGE - Amazon Ground Emissions Program
AGU - American Geophysical Union
ASDC - Atmospheric Science Data Center
DADS - Data Acquisition and Display System
EOSDIS - Earth Observing System Distributed Information System
GTE - Global Tropospheric Experiment
IAG - Instituto Astronomico e Geofisico
IMS - Information Management System
INPE - Instituto Nacional de Pesquisas Espaciais (National Institute for Space Research)
NASA - National Aeronautics and Space Administration
NCAR - National Center for Atmospheric Research
ProjDP - Project Dew Point
TSCALC - Static temperature, calculated by DADS
TSDEGC - Static temperature, measured directly, in Celsius
WFF - Wallops Flight Facility

Creation Date: November 2003
Revision Date:
Review Date:
Identification:
Curator: Langley DAAC User and Data Services Office
ASDC Help Desk: Telephone (757) 864-8656; E-mail larc@eos.nasa.gov
URL: http://eosweb.larc.nasa.gov/GUIDE/dataset_documents/gte_able_2a_dataset.html