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Global Tropospheric Experiment Chemical Instrumentation Test and Evaluation-3 (CITE 3) Langley ASDC Document Data Set Document |
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This document provides information on data products obtained during the GTE CITE 3 atmospheric science expedition conducted over the North and South Atlantic Ocean during August and September 1989. The objective of the mission was to evaluate instrumentation for the airborne measurement of sulfur dioxide, hydrogen sulfide, carbon disulfide, dimethyl sulfide and carbonyl sulfide. 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 three data sets:
The investigators involved in the CITE 3 mission were funded by NASA. The funded investigators, their organizations, their grant, agreement or contract numbers were:
| Investigator | Organization | Grant |
|---|---|---|
| Aircraft: | ||
| A. R. Bandy | Drexel U | NAG-1-926 |
| J. Bradshaw | Georgia Tech | NAG-1-818 |
| S. O. Farwell | U of Idaho | NAG-1-923 |
| R. J. Ferek | U of Washington | NAG-1-925 |
| G. L. Gregory | NASA Langley | N/A |
| J. E. Johnson | NOAA/PMEL | L-46397C |
| G. W. Sachse | NASA Langley | N/A |
| E. S. Saltzman | U of Miami | NAG-1-918 |
| D. C. Thornton | Drexel U | NAG-1-927 |
| Mission Scientist: | ||
| D. D. Davis | Georgia Tech | NCC-1-133 |
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 multi-altitudes during flight from the intensive sites. Flight missions were conducted during CITE 3 from August through September 1989. 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 Hoell et al., [1993]. 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. 98, No. D12, December 20, 1993.
This data set contains all of the data submitted to the GTE data archive by the CITE 3 investigators listed in Section 1.d. Included are the atmospheric chemistry, meteorological and navigational data recorded aboard the NASA Wallops Electra airborne laboratory.
The atmospheric species and other parameters measured are listed in Section 4.c and in Hoell et al., [1993]. Also listed for each are the name and affiliation of the principal investigator.
CITE 3 investigators have individually reported the results of their investigations in the Journal of Geophysical Research, Vol. 98, No. D12, December 20, 1993.
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 Chemical Instrumentation Test and Evaluation-3 (CITE 3)
If the person is known to be retired, deceased or no longer at the organization originally responsible for this 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.
The following persons have either specialized knowledge in their field or general knowledge about the mission, its execution and the data sets.
Volker W. J. H. Kirchhoff
Instituto de Pesquisas Espaciais
C. P. 515
12200 - Sao Jose dos Campos - SP
Brazil
Telephone: 55-123-229977
B. G. Motta
Instituto de Pesquisas Espaciais
C. P. 130
59000 - Natal - RN
Brazil
Telephone: 55-847-2314733
Potential usage and applications of the described data sets can be seen in the articles that comprise the Journal of Geophysical Research CITE 3 Special Section (Vol. 98, No. D12 December 20, 1993) and the 1990 Fall AGU Meeting.
For convenience of the users, the calculated variables below are provided.
Mach Number, M: |
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M = Mach Number Ps = Static Pressure Qc = Differential Pressure |
Static Air Temperature, Ts: | |
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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: | |
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TAS = True Air Speed (knots) TS = Static Air Temperature (°K) M = Mach Number a = Speed of Sound |
Potential Temperature, θ: | |
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θ = Potential Temperature (°K) TS = Static Air Temperature (°K) Ps = Static Pressure (mb) |
Vapor Pressure, e :
ewater (mb) = [1.0007 + (3.46 * 10-6 * PS)] * 6.1121* EXP[17.502 * T/(240.97 + T)]
eice (mb) = [1.0003 + (4.18 * 10-6 * PS)] * 6.1115* EXP[22.452 * T/(272.55 + T)]
e = Partial Pressure of Water Vapor (mb)
PS = Static Pressure (mb)
T = Static Air Temperature (°C) for Saturation Vapor Pressure
or
T = Dew/Frost Point (°C) for Partial Pressure of Water Vapor
ProjDP of zero or greater should be used to derive the partial pressure of water vapor w.r.t water (ewater ) and the ProjDP less than zero should be used to derive the partial pressure of water vapor w.r.t ice (eice).
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.
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: | |
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Mixing Ratio, r: | |
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| Note: ppmv = 1.608 * ppmw ppmw = 0.622 * ppmv | |
Relative Humidity, %: | |
w.r.t. water,![]() |
w.r.t. ice,![]() |
Interested readers should see the Journal of Geophysical Research, Vol. 98, No. D12, December 20, 1993, and documents referenced therein, for plots and the results of analysis of data.
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 generally available for each investigation for each flight. Surface level data are available on a daily basis.
All data for the CITE 3 mission is contained in the archive. No additional data products relevant to CITE 3 are anticipated. Hoell et al., [1993] indicates which instruments have measurements for which flights.
This data is available online or on a CDROM via the LaRC ASDC at http://eosweb.larc.nasa.gov.Users may also order data by letter, telephone, or electronic mail (see 3e).
The Atmospheric Science Data Center at NASA's Langley Research Center.
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. 98, No. D12, December 20, 1993.
Airborne measurements were made over the north and tropical Atlantic Ocean, as indicated in Hoell et al., [1993]. 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. 98, No. D12, December 20, 1993. 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.
As discussed in Hoell et al., [1993] flight missions were conducted during August and September 1989. The duration, altitude range, assent and descent rate, and flight path of each mission varied depending on mission objective and environmental conditions. With the CITE-3 payload, the NASA Electra aircraft operated over a nominal altitued range from 0.2 km to 5.5 km. Hoell et al., [1993] schematically shows the variation of airplane flight patterns used during the flights.
| North Atlantic | Tropical Atlantic | |||||||
|---|---|---|---|---|---|---|---|---|
| Data Set Name | Min Lat | Max Lat | Min Lon | Max Lon | Min Lat | Max Lat | Min Lon | Max Lon |
| Listing of individual PI-files | 32N | 40N | 70W | 75W | 12S | 2N | 25W | 35W |
| Listing of merged data files | 32N | 40N | 70W | 75W | 12S | 2N | 25W | 35W |
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.
CITE 3 aircraft missions were conducted from August 22 to September 22, 1989. The dates and times for each mission are given in Hoell et al., [1993]. Ground site measurements were obtained from (date) to (date).
| North Atlantic | Tropical Atlantic | |||
|---|---|---|---|---|
| Data Set Name | Begin Date | End Date | Begin Date | End Date |
| Listing of individual PI-files | August 22, 1989 | September 1, 1989 | September 12, 1989 | September 22, 1889 |
| Listing of merged data files | August 22, 1989 | September 1, 1989 | September 12, 1989 | September 22, 1889 |
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 Hoell et al., [1993].
The sources of error vary depending on species and measurement environment and are addressed in the papers included in the CITE 3 special section of the Journal of Geophysical Research, Vol. 98, No. D12, December 20, 1993, and/or papers referenced in that publication and readme files and/or header records associated with each data file.
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.
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 CITE 3 Special Section (Vol. 98, No. D12, December 20, 1993) and the 1990 AGU Fall Meeting.
AGU Fall Meeting, San Francisco, CA, 3-7 December 1990.
CITE 3 Special Section, Journal of Geophysical Research, Vol. 98, No. D12, 20 December 1993.
GTE Bibliography (http://www-gte.larc.nasa.gov/gte_pubs_update.htm)
Hoell, J. M., D. D. Davis, G. L. Gregory, R. J. McNeal, R. J. Bendura, J. W. Drewry, J. D. Barrick, V. W. J. H. Kirchhoff, A. G. Motto, R. L. Navarro, W. D. Dorko, and D. W. Owen, Operational Overview of the NASA GTE/CITE 3 Airborne Instrument Intercomparisons for Sulfur Dioxide, Hydrogen Sulfide, Carbonyl Sulfide, Dimethyl Sulfide, and Carbon Disulfide, J. Geophys. Res., Vol. 98, No. D12, 23291-23304, 20 December 1990.