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GLOBAL TROPOSPHERIC EXPERIMENT
Data Archive Format
GTE Project Office
Mail Stop 483
National Aeronautics and Space Administration
Langley Research Center Hampton,
VA 23681-2199
Data Archive Format
August, 2000
Prepared by
Dennis W. Owen
Revised by Ali A. Aknan1 and A. Don Scott2 In Partial
Fulfillment of NAS1-19570
1Science Applications International Corporation
2NASA Langley Research Center Chemistry & Dynamics Branch
GTE DATA ARCHIVE FORMAT
Table of Contents
I. GENERAL INSTRUCTIONS AND RATIONALE
The data format described herein is designed to provide a file
structure that effectively utilizes computer storage media for
the exchange of data for scientific analysis. Recognizing that
the variety of GTE measurement techniques span a large dynamic
data range, every attempt has been made to meet the needs of scientists
that generate either large or small data sets. The GTE Data
Archive Format is intended to satisfy both the data archive
and data exchange requirements of the GTE field expeditions.
I.A. SUITABLE MEDIA
Files must be in ASCII. All data should be numeric, separated
by commas. Each aircraft PI shall submit a minimum of one file
per flight. Whenever possible, data shall be submitted to the GTE
Data Archive via electronic transfer. Suitable media include File
Transfer Protocol (FTP), electronic mail (E-mail), and IBM-compatible
diskettes (3.5" High Density preferable). The file size should
be compatible with the submitting media limitations. Therefore,
if the ASCII file size is greater than 1.44 mb, it should either
be compressed before being submitted on 3.5" disks, or it
should be submitted via FTP or E-mail. If data are compressed using
non-standard compression software, either the un-compressing programs
must be included with the data, or the data should be in executable
form (.EXE file extension). Large files can be most easily accommodated
via electronic submissions directly into the GTE Archives (Refer
to Section V. FTP Protocol for GTE Data Exchange). As mediums of
data exchange are constantly being upgraded and amended, and as
new mediums of exchange introduced, the GTE Data Archive Office
will continue to upgrade and change its data exchange processes
when feasible. Any medium of exchange differing from those mentioned
in this document should be approved by the GTE Data Archive Office
prior to data submittal.
A file containing header records in the GTE Data Archive format
shall be submitted with each mission data set. The file shall describe
the data submitted, how to locate and access it, and the data file
structure. See Section I.B. Common File Structure for more information
and guidance on constructing the file.
The requirement to submit files of header records to describe
both the data and data access procedures applies also to hardcopy
submittals..
I.B. COMMON FILE STRUCTURE
A GTE Archive file is composed of two sections: a HEADER SECTION,
which contains all the information with which to process the file;
and the DATA SECTION, which contains the data in the prescribed
GTE Data Archive format. The file naming convention, header and
data format descriptions are detailed in Section 2 of this document.
In order to facilitate the exchange of data among the GTE investigators
and the scientific community at large, the GTE format requires
that all datasets be referenced by time. Time data is composed
of the Julian day of the year and the seconds of the day, both
referenced to Greenwich Mean Time (GMT). When a reporting period
extends past GMT midnight (86,400 seconds), increment the Julian
day of year and reset the time to zero. See Section II.C Dataset
Types for an explanation of the different time reporting options.
Aircraft PI's should submit a file for each aircraft mission.
If no data are submitted to the archive for a particular mission,
the PI shall in any case submit a file containing the Header section
of the GTE Data Archive format. The PI shall use comment records
to explain the reasons no data are provided for the mission. The
requirement to submit files of header records to describe both
the data and data access procedures applies also to hardcopy submittals.
II. HEADER RECORD FORMAT
This section contains a detailed description of the format for
each header record. The header records should supply all information
needed to read and interpret the data records. Even if the actual
data are not included in the file, the header records should include
the parameters as noted and information needed to identify and
locate the data files.
II.A. Definition of Header Records
Each line of the header section is reserved for specific information.
These headers will be scanned by computer programs; therefore,
all data must be in the format as described in order to be correctly
interpreted. The following sections define each line of the Header
Record Format.
Line 1. Number of Lines in the Header (NH)
The first line in the header contains the number of lines in the
header section (NH). The first line of data = NH + 1.
Line 2. File Name:
The second line in the header contains the name of the dataset
file. The data file naming convention for the GTE is as follows:
PPTTTLXX.EXP where:
PP = 2-character code identifying PI. See Table-1 for appropriate
code.
TTT = 3-character code identifying data set or instrument technique.
L = Location code: 'D' for DC-8 aircraft, 'P' for P3-B, 'E' for
Electra aircraft. Codes for other locations will be provided by
the GTE Project Office.
XX = 2-digit numeric mission descriptor . For a flight, XX = flight
number; for ground-based data, this may be a sample number or day
identifier.
EXP = Expedition Code. See Table-2 for appropriate code.
NOTE: For aircraft investigators, each landing constitutes
a new flight. Flights are named by integer numbers only (i.e. there
can not be a flight named 21A or 21.1). If there are several flights
on a day, each flight will receive a separate numeric identifier.
Examples follow:
DU_SUD01.PWB = Drexel University sulfur data for DC-8 Flight 1,
for the PEM West-B Expedition (Replace any unused code letters
with an underline "_")
POM10D05.TRA = Project Navigational/Meteorological 10-second data
for DC-8 Flight 5, for the TRACE-A Expedition
Line 3. Principal Investigator
Line 3 contains the PI Last Name, First Name, and Institution.
Always separate items by commas.
Line 4. Species Measured / Technique Used.
Line 4 contains a brief summary of the species measured and the
method employed for this sampling. For example, nonmethane hydrocarbons
should be entered here rather than listing each species. Use only
one line.
Line 5. Expedition Name
The Official name for this expedition. Please refer to Table-2 for
Expedition Names and their abbreviations.
Line 6. Data Start Date, Date Last Revised (YY,MM,DD,YY,MM,DD)
Line 6 contains two dates. Report the start date for this dataset,
followed by the date of last revision, both in the format YY,MM,DD
Line 7. Number for this Flight, or Sequential Dataset Number
(NF)
Line 7 contains a unique number for this dataset (NF). For aircraft
datasets, this number is the number for this flight. For ground-based
datasets, this is usually a sequential number starting at "01" for
the first dataset submitted.
Line 8. Number of Variables Reported in this Dataset (NV)
For most standard datasets, the number of variables remains constant
for each line in the dataset (Dataset Types 1, 2, 4 and 6). In
those cases, NV = number of variables for each dataset submitted.
Several dataset types are defined which include a matrix of data
whose dimensions may vary between dataset records. For these datasets,
the matrix variable is considered as a single variable and is always
the last variable reported in the list. The variable or variables
immediately proceeding the dimensioned variable will contain the
number of elements in the matrix. In these cases, NV = number of
unique variables for each record in the dataset, with the matrix
being considered as a single variable. Refer to Header Sample Descriptions
3 and 5 for a complete explanation and examples of this variable.
Line 9. Number of Comments (NC)
Line 9 contains the number of comment lines included in the header
for this dataset. Comment lines should include any pertinent information
needed to help the scientific community correctly interpret the
dataset, such as accuracy, precision and limits of detection of
the instrument (where applicable). Listing a point of contact is
encouraged.
Both precision and accuracy contribute to total uncertainty. In
general, precision refers to the random component of total uncertainty,
while accuracy refers to any systematic errors. Precision can be
statistically determined and is often referred to as "noise";
whereas, accuracy is often a more subjective judgement typically
associated with potential errors in calibration standards or methods.
Where applicable, a lower and upper limit of detection for an
instrument should be provided for each parameter measured.
Line 10. Dataset Type (DT)
The GTE Data Archive Format currently supports seven (7) Dataset
Types, numbered from 0 to 6. The seven Dataset Types are:
Data Type = 0 : Non-standard reporting of time of samples.
Data Type = 1 : Standard reporting of time as the midpoint of
a standard averaging period.
Data Type = 2 : Standard reporting of time as start, stop, and
midpoint of a non-standard averaging period.
Data Type = 3 : Vertical Column Sample. Non-standard sampling
using a variable number of sampling points in the sample.
Data Type = 4 : Vertical Column Sample. Standard submission for
sonde data.
Data Type = 5 : Gridded Dataset. Submission standards for mapping
products such as the AVHRR Fire Counts maps.
Data Type = 6 : Trajectory Dataset. Trajectory data follows a
particular air parcel over a finite period of time and records
values at regular intervals over the period.
Refer to Section II.C. Dataset Types for a complete description
and examples of the seven dataset types.
Line 11. Data Averaging Period
Refer to Section III.A. Time Reference.
Line 12. Data Sampling Frequency (Hertz)
Enter the instrument sampling frequency, in hertz. Data recorded
at 1 sample/second = 1 Hz; 5 samples/second = 5 Hz; 1 sample every
5 seconds = 0.2 Hz.; 1 sample / minute = 1/60 = 0.0167 Hz. Enter "0" here
for instruments having non-standard sampling periods. For Data
Type = 6, replace this variable with the number of Samples per
Trajectory.
Lines 13 thru Line 13+NV-1 contain the definition of variables
used in the dataset as described in section II.B.
II.B. DATA VARIABLE DEFINITION
Each variable is defined on a separate line in the Header. Each
variable definition is composed of a minimum of eight (8) parameters,
separated by commas. The eight required parameters are:
Variable Name, Units, ScaleFactor, Offset, Minimum, Maximum,
Null Code, LOD Code
If Limits of Detection (LOD's) are used in the dataset, then an
additional four parameters are added to the end of the above definition
line:
Lower LOD Code, Lower LOD Value, Upper LOD Code, Upper LOD
Value
Variable Definition in the Header:
Item 1. Variable Name: Name of Data Variable. (Time, Day,
Chemical Species, etc..)
Item 2. Units: Units of Data Variable.
Item 3. ScaleFactor: Scale Factor (Gain) of Data Variable.
Item 4. Offset: Offset of Data Variable.
Item 5. Minimum: This is the Reported Minimum Value found
for this variable in the dataset (excluding Null and LOD codes),
not an absolute minimum value that could be experienced for this
variable. For TIME, use the first sample time reported in the dataset.
The actual Minimum Value (Engineering Units)is computed using the ScaleFactor and Offset given
for the variable, such that :
Minimum Value (Engineering Units) = Reported Minimum Value
* ScaleFactor + Offset
Item 6. Maximum: This is the Reported Maximum Value (Engineering
Units) found for this variable in the dataset (excluding Null and
LOD codes), not an absolute maximum value that could be experienced
for this variable. For TIME, use the last sample time reported
in the dataset. The actual Maximum Value (Engineering Units) is
computed using the ScaleFactor and Offset given for
the variable, such that :
Maximum Value (Engineering Units) = Reported Maximum Value
* ScaleFactor + Offset
Item 7. Null Code: This code is used for missing or bad
data. This code is composed of a series of negative nines (-9's)
which will be outside the range of actual data or one digit larger
when the actual Minimum Value is negative. No ScaleFactor
and Offset are applied to this Code. The code reported here
should be to the same number of significant digits as the
actual archived Data Value.
NOTE: Scale factors and offsets are applied on ALL reported
data, such that:
Data Value (Engineering Units) = ReportedData Value * ScaleFactor
+ Offset
This means that ScaleFactors and Offsets are first applied
on the archived data to arrive at the true data value, in Engineering
Units. It is preferable that data be submitted such that Scale
Factors = 1 and Offsets = 0.
Example 1. Variable Name = Static Air Temp, Units = DegC,
Scale Factor = 1.0, Offset = 0.0, Reported Maximum Value = 59.9,
Reported Minimum Value = 8.5, LOD Code = 0 (see Item 8);
therefore, variable definition:
Static Air Temp, DegC, 1.0, 0.0, 8.5, 59.9, -9.9, 0
NOTE: The Null Code is beyond the range of actual data.
Example 2. Variable Name = Static Air Temp, Units = DegC,
Scale Factor = 1.0, Offset = 0.0, Reported Maximum Value = 59.9,
Reported Minimum Value = -125.4, LOD Code = 0; therefore,
variable definition:
Static Air Temp, DegC, 1.0, 0.0, -125.4, 59.9, -9999.9, 0
Example 3. Variable Name = Static Air Temp, Units = DegC,
Scale Factor = 10.0, Offset = 0.0, Reported Maximum Value
= 5.99, Reported Minimum Value =-12.54, LOD Code = 0; therefore,
variable definition:
Static Air Temp, DegC, 10.0, 0.0, -12.54, 5.99, -9999.9, 0
NOTE: The Null Code is one digit larger than the Actual
Data Minimum
(-12.54 *10.0 + 0.0 = -125.4).
Item 8. LOD Code : Acceptable values are 0, 1, or 2.
0 : There are no Limits of Detection given for this variable.
1 : The Limits of Detection for this variable are varying with
time. Items 10 and 12 are pointers to variables in the dataset
which contain the actual LOD Values for this variable. See Items
9-12 for further explanation of this code.
2 : The Limits of Detection for this Variable are constants. Items
10 and 12 contain the actual LOD Values for this variable.
Items 9-12 are used only when Limits of Detection are given
(i.e., LOD Code = 1 or 2).
Item 9. Lower Limit of Detection Code (L_LOD Code) :
This code is used when Lower Limit of Detection for this variable
is to be reported. This code is composed of a series of negative
eights (-8's) which will be outside the range of actual data or one
digit larger when the actual Minimum Value is negative. No
ScaleFactor and Offset are applied to this Code. The code reported
here should be to the same number of significant digits as
the actual Reported Data Value.
Item 10 : Lower Limit of Detection Value (L_LOD Value)
If LOD Code = 1, L_LOD Value = Variable column number containing
the actual L_LOD Values.
If LOD Code = 2, L_LOD Value = Actual Lower LOD Value.
Item 11 : Upper Limit of Detection Code (U_LOD Code) :
This code is used when Upper Limit of Detection for this variable
is to be reported. This code is composed of a series of negative
sevens (-7's) which will be outside the range of actual data or one
digit larger when the actual Minimum Value is negative. No
ScaleFactor and Offset are applied to this Code. The code reported
here should be to the same number of significant digits as
the actual Reported Data Value.
Item 12 : Upper Limit of Detection Value (U_LOD Value)
If LOD Code = 1, U_LOD Value = Variable column number containing
the actual U_LOD Values.
If LOD Code = 2, U_LOD Value = Actual Upper LOD Value.
NOTE: Scale factors and offsets are applied on reported
LOD Values, such that :
LOD Value (Engineering Units) = Reported LOD Value * ScaleFactor
+ Offset
Examples of LOD Codes:
LOD Code = 0
No LOD's for this variable.
LOD Code = 1
This code assumes the Limits of Detection for this flight were
changing with time. Assume this is Var_3, and data reported has
one significant digit, with Min = 2.1; Max = 155.8; Scale Factor
= 1.0, and Offset = 0.0; the actual limits of detection values
are stored in column 4 of this dataset. Therefore:
L_LOD Code = -8.8 (beyond the normal data range)
U_LOD Code = -7.7
L_LOD Value = 4. Var_4(t) contains the actual L_LOD Values when
Var_3(t) = -8.8.
U_LOD Value = 4. Var_4(t) contains the actual U_LOD Values when
the Var_3(t) = -7.7.
NOTE: when Var_3(t) contains real data, Var_4(t) should
contain the Null Code (-9.9).
The variable definition in the Header:
Var_3's Name, Var_3's Units, 1.0, 0.0, 2.1, 155.8, -9.9, 1,
-8.8, 4, -7.7, 4
Thus, if Var_3(t) contains L_LOD Code (-8.8), instrument has detected
data below its lower limits of detection (L_LOD Value). Refer to
Var_4(t) for actual L_LOD Value for this time period. If Var_3(t)
contains U_LOD Code (-7.7), observed data are above the upper limits
of the instrument (U_LOD Value). Refer to Var_4(t) for the actual
U_LOD Value for this time period.
LOD Code = 2
This code assumes the Limits of Detection for this flight were
constant. Assume this is Var_3, and data reported has one significant
digit, with a Reported Min = 2.1; Max = 15.8; Scale Factor = 10.0,
Offset = 0.0; Reported Lower limits of detection = 1.5; and Upper
limits of detection = 20. Therefore,
L_LOD Code = -8.8 (beyond the normal data range)
U_LOD Code = -7.7
L_LOD Value = 1.5.
U_LOD Value = 20.
The variable definition in the Header:
Var_3's Name, Var_3's Units, 10.0, 0.0, 2.1, 15.8, -9.9, 2,
-8.8, 1.5, -7.7, 20.0
Thus, if Var_3(t) contains L_LOD Code (-8.8), instrument has detected
data below its L_LOD Value. This L_LOD Value (15 = 10 * 1.5 + 0)
is defined in the Header for this variable. Likewise, if Var_3
contains U_LOD Code (-7.7), instrument has detected data above
its U_LOD Value. This U_LOD Value (200 = 10 * 20 + 0) is defined
in the header for this variable.
Lines 13 thru 13+NV-1 in the Header:
Line 13. Definition of the First Variable in the Dataset :
Var_1
This variable must be the Julian Day of the Year (GMT) when the
sample were taken. If the samples span two days, this is the start
day of the samples. A minimum of eight parameters are necessary
for this Variable Definition. They are:
Variable Name, Units, Scale, Offset, Minimum, Maximum, Null
Value, LOD Code
Line 14. Definition of the Second Variable in the Dataset :
Var_2
The second variable must be time in seconds, GMT. For Data Type
1, this is the median time of the sampling period. For all other
Data Types, this is the Start Time of the sample. (The start time
will be null (-9's) in the case of data type 5). Refer to Section
II.C for further explanation.
Line 15 Definition of the Third Variable in the Dataset : Var_3
Refer to the Header Sample Descriptions (Figures 0-6) for any
standard definitions for this record.
Line 13+NV-1: Definition of the last variable in the dataset,
Var_NV
Line 13+NV: First line of Comments.
This line contains the first line of comments for this header.
If NC = 0, then there are no comment lines in the dataset.
Line 13+NV+NC-1: Last line of Comments.
This is the last line of comments for this header.
Line 13+NV+NC: First line of Data.
This is the first line of data for this dataset. This location
is the same as Number of Lines in the Header (NH)+1 (Header
line 1 defines NH)
II.C. DATASET TYPES (DT)
Data reporting frequency is a function of instrument response,
data processing, and the temporal variability of the measured quantity.
Some investigators sample at 1Hz or faster, while others employ
measurement techniques that require several minutes to obtain a
sample, such as grab samples. In order to facilitate the intercomparison
of data and merging of data sets for scientific studies, the GTE
Data Archive format provides standard reporting capabilities for
instruments as diverse as fast-response chemical measurements,
grab samples, and processed fire counts mapping from satellites.
The GTE Data Archive Format currently supports seven (7) Standard
Dataset Types, numbered from 0 to 6. This value is reported on
line10 of the Header Record. A description of these parameters
follows.
Sample Description 0.(DT = 0) : Non-standard Dataset, Non-constant
time increment. Time reported as the sampling time. Report "0" in
the 12th header record for sampling frequency (see Variable Interval
Time Reporting). This dataset type should be used by experimenters
who take samples at irregular time intervals. The first two variables
must be:
Var(1) : Julian Day of the Year (GMT)
Var(2) : Time (Seconds GMT) - Time of sample.
Refer to Header Sample Description 0 [FIGURE-0] for an
example of this dataset type.
Sample Description 1.(DT = 1) : Standard Dataset, Constant
time increment. Time reported as the time of sample or midpoint
of the averaging period. Time between 2 consecutive records must
equal to the averaging period. If data is reported as collected,
the averaging period should be the same as the sampling frequency.
For example, if data was collected and reported at 2 Hz, the averaging
period should be set to 0.5 and the sampling frequency to 2 (See
Constant Interval Time Reporting for a discussion of midpoint reporting.)
Most instruments using a constant time interval between samples
can utilize this dataset type. The first two variables must be:
Var(1) : Julian Day of the Year (GMT)
Var(2) : Time (Seconds GMT) - Time of sample or Midpoint of Averaging
Period. See Constant Interval Time Format section.
Refer to Header Sample Description 1 [FIGURE-1] for an
example of this dataset type.
Sample Description 2.(DT=2) : Standard Grab Sample, Non-standard
time increment. The sampling frequency and/or averaging period
are non-constant (see Variable Interval Time Reporting). For non-constant
sampling frequency, report "0" in the 12th header record.
This dataset type should be used by experimenters who take and
report samples at non-constant sampling times and periods. When
reporting intervals are irregular, it is necessary to report the
sample start time, end time, and the midpoint time for each record.
The first four variables must be:
Var(1) : Julian Day of the Year (GMT) of the Sample Midpoint
Var(2) : Sample Start Time (Seconds of the Day, GMT)
Var(3) : Sample Stop Time (Seconds of the Day, GMT)
Var(4) : Sample Midpoint (Seconds of the Day, GMT)
Refer to Header Sample Description 2 [FIGURE-2] for an
example of this dataset type.
Sample Description 3.(DT = 3) : Vertical Profile Sample,
with a variable number of points in the sample. Variable "nv" defines
the number of variables, with the last variable being an array
dimensioned Var(nv). For example, if nv = 8, then variable 8 contains
the number to dimension the profile array variable. The first two
variables must be:
Var(1) : Julian Day of the Year (GMT) of the Sample Start Time
Var(2) : Sample Start Time (Seconds of the Day, GMT)
The final two variables must be:
Var(nv-1) : Number of profile data values for this sample
Var(nv) : Profile array, dimensioned Var(nv-1)
Refer to Header Sample Description 3 [FIGURE-3] for an
example of this dataset type.
Sample Description 4. (DT = 4) : Vertical Profile Sample,
Standard Sonde Data. This dataset type follows the example of DT
1, except that time is not constant. The first two variables must
be:
Var(1) : Julian Day of the Year (GMT) of this altitude
Var(2) : Time of this altitude (Seconds of the Day, GMT)
Refer to Header Sample Description 4 [FIGURE-4] for an
example of this dataset type.
Sample Description 5.(DT = 5) : Standard Gridded Data,
Gridded Map Data. This dataset type is constructed to enable investigators
to submit satellite data to the Archive, for example, AVHRR Fire
Count data maps. It is assumed that these datasets are geographically
rectified to a given latitude and longitude at a given time. This
data type requires the following variables:
Var(1) : Start Julian Day of the Year (GMT)
Var(2) : Start Time of the Scan (Seconds, GMT)
Var(3) : Stop Julian Day of the Year (GMT)
Var(4) : Stop Time of the Scan (Seconds, GMT)
Var(5) : Start Latitude of the scan, Degrees North = positive
Var(6) : Start Longitude of the scan, Degrees East = positive
Var(7) : Latitude Increment , Degrees North . Add the Latitude
Increment to the Start Latitude to find the second row of the scan.
If the Latitude Increment is positive, scan is going from south
to north; negative is north to south.
Var(8) : Longitude Increment, Degrees East. Add the Longitude
Increment to the Start Longitude to find the second column of the
scan. If the Longitude Increment is positive, the scan is going
from west to east; negative is east to west.
Var(9) : Number of Rows of Latitude (NRows)
Var(10) : Number of Columns of Longitude (NCols) :
Var(11) : Pixel Data (NRows, NCols). The data is gridded by Latitude
(NRows) and Longitude (NCols) and is presented as scan lines of
longitude, one data record for each Latitude Increment. A simple
decode program flow for the data scans follows:
DIM PixelData(NRows,NCols)
FOR i = 1 to NRows
' read in a line of data for a constant Latitude
For j = 1 to NCols
INPUT filenumber, PixelData(i , j)
NEXT j
NEXT i
The dimensioned variable PixelData will now contain the entire
matrix of data for this image. Geographically rectify the image
using the Start Latitude and Start Longitude and incrementing each
correctly. Refer to Header Sample Description 5 [FIGURE-5] for
an example of this type of dataset.
Sample Description 6.(DT = 6) : Standard Trajectory Dataset.
Trajectory data report samples from a particular air parcel over
a finite period of time. Each trajectory in the dataset must contain
the same number of data points, defined by Header Line 12. The
first data line contains data from the trajectory end point, corresponding
to a selected aircraft time and position. Each following line is
the trajectory's position on the previous time step. Time steps
prior to the start time are all normalized according to the Data
Averaging Period defined in Header Line 11. Refer to Header Sample
Description 6 [FIGURE-6] for an example of this type of
dataset.
III. DATA RECORD FORMAT
The Data Record section begins on line NH+1 (one line after the
header). For each record, data should be reported in the sequence
as stated in the Header Record. Each reported value in the dataset
utilizes the scale factor and offset for that variable so that
Reported DataValue * ScaleFactor + Offset = Engineering
Units
Only numeric values are acceptable as data for the standard archive
data types. Please contact the GTE Data Management Office if your
data cannot meet this criteria. It is preferable that data be reported
in engineering units such that Scale Factors = 1 and Offsets =
0. If data is missing, or is above or below the Limits of Detection
(LOD), use the appropriate code as stated in the variable definition
for that variable in the header. These special codes should be
entered exactly as stated in the Variable Definition Section so
that computer programs can correctly determine validity. For example,
if the null value is defined as -9.99 for a variable in the Variable
Definition Section, that value should be used in the data for the
null value. Scale factors and offsets are NOT applied to
any codes in the data.
Note that uncertainties (e.g., ) associated with a given measurement
may be included in the archive as a variable.
III.A. TIME REFERENCE
All data should be referenced to day of the year (Julian Day)
and Greenwich Mean Time (GMT seconds of the day). When a reporting
period extends past GMT midnight (86,400 seconds), increment the
Julian day of year and reset the time to zero. Please refer to
Section II.C. Dataset Types for a complete list of required variables
for each dataset.
For DT2 files where START, STOP, and MID times are required and
when time extends past GMT midnight (i.e., STOP time is greater
than 86400), report STOP, and MID times without any resetting for
this particular record. Thus, STOP and/or MID times could be greater
than 86400. Then, JDAY for the next record should be incremented
by one and START, STOP, and MID times resetted.
III.A.1. CONSTANT INTERVAL TIME AVERAGING
REPORTING
Report the Data Averaging Period in the 11th header record. For
a 10-second reporting interval, report data at 5-second time ticks;
i.e., 5, 15, 25,... GMT seconds. Thus, the data value reported
at 15 seconds represents the average value in the interval equal
to or greater than 10 seconds and less than 20 seconds.
For 60-second data (1-minute averages), the reporting times should
be at 30-second time ticks; i.e., 30, 90, 150,... GMT seconds.
Thus, the data value reported at 90 seconds represents the average
value in the interval equal to or greater than 60 seconds and less
than 120 seconds. Data reported in 60-second time intervals would
be reported in the same format as for 10-second reporting, except
the data reporting interval in header record 12 would be 60.
For other constant time intervals, time ticks of the data reporting
interval should be consistent with the 10-sec or 60-sec format.
III.A.2 VARIABLE INTERVAL TIME REPORTING
Report "0" for the Data Averaging Period in the 11th
header record when reporting intervals are irregular.
1.SAMPLE DATA FILES
FIGURE-0: Header Sample Description 0 Non-standard
Dataset: Non-constant Time Increment
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
19
|
|
2
|
FileName
|
SHGC_D10.PMT
|
|
3
|
Experimenter name, Instit.
|
Singh, Hanwant, NASA-ARC
|
|
4
|
Species
|
PAN/C2Cl4: GC
|
|
5
|
Expedition
|
PEM-Tropics
|
|
6
|
Flt Date, Rev Date
|
96,09,14,96,12,05
|
|
7
|
NF
|
10
|
|
8
|
NV
|
4
|
|
9
|
NC
|
3
|
|
10
|
DT
|
0
|
|
11
|
Avg Period
|
0
|
|
12
|
Samp Freq
|
0
|
|
13
|
Var(1)
|
Day, Julian(GMT), 1, 0, 258, 258, -999, 0
|
|
13+1
|
Var(2)
|
Time, Sec(GMT), 1, 0, 65251, 85486, -999, 0
|
|
13+2
|
Var(3)
|
Pan, ppt, 1, 0, 4.4, 113.0, -999, 0
|
|
13+3
|
Var(4)
|
c2cl4, ppt, 1, 0, 1.2, 4.1, -999, 0
|
|
13+nv
|
Comment 1
|
time given is end of sampling period (subtract 150 secs
to get start time)
|
|
13+nv+1
|
Comment 2
|
data lines alternate between pan channel 1 & pan channel
2
|
|
13+nv+2
|
Comment 3
|
sampling period length is 150 seconds
|
|
13+nv+nc or nh + 1
|
Data Rec 1
|
258,65251,4.4,3.4
|
|
nh + 2
|
Data Rec 2
|
258,65476,14.5,4.1
|
|
nh +3
|
Data Rec3
|
258,65941,13.2,2.3
|
FIGURE-1: Header Sample Description 1 Standard
Dataset; Time at Midpoint
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
61
|
|
2
|
FileName
|
BJXY2D03.TRA
|
|
3
|
Experimenter name, Instit.
|
John Bradshaw & Scott Sandholm, GA. INST. OF TECH.
|
|
4
|
Species
|
NxOy/PF-LIF
|
|
5
|
Expedition
|
TRACE-A
|
|
6
|
Flt Date, Rev Date
|
92, 09, 21, 93, 06, 01
|
|
7
|
NF
|
3
|
|
8
|
NV
|
17
|
|
9
|
NC
|
32
|
|
10
|
DT
|
1
|
|
11
|
Avg Period
|
90
|
|
12
|
Samp Freq
|
1
|
|
13
|
Var(1)
|
Day, Julian (GMT), 1, 0,265, 265, -999, 0
|
|
13+1
|
Var(2)
|
Time, Sec (GMT), 1, 0, 63463, 72883, -999, 0
|
|
13+2
|
Var(3)
|
[NO], (pptv), 1, 0,9.0, 595.0, -999.9, 1, -888.8, 9, -777.7,
9
|
|
13+3
|
Var(4)
|
sigma_NO, (pptv), 1, 0, 2.7, 18.0, -999.9, 1, -888.8,
10, -777.7,10
|
|
13+4
|
Var(5)
|
[NO2], (pptv), 1, 0, 34.5, 139.0, -999.9, 1, -888.8, 11,
-777.7,11
|
|
13+5
|
Var(6)
|
LV_[NO], (pptv), 1, 0, -999.9, -999.9, -999.9, 0
|
|
13+6
|
Var(7)
|
LV_NO_sigma, (pptv), 1, 0, -999.9, -999.9, -999.9, 0
|
|
13+7
|
Var(8)
|
LV_[NO2], (pptv), 1, 0, 30.4, 78.3, -999.9, 0
|
|
13+nv-1
|
Var(nv)
|
NOy_com_code, , 1, 0 , 0, 6, -9,0
|
|
13+nv
|
Comment 1
|
The variable names that start wi th a "LV" are
limiting values, either an upper
|
|
13+nv+1
|
Comment 2
|
or lower limit, (see the coding in the column for that
molecule for details).
|
|
13+nv+2
|
Comment 3
|
The reported time is the center point of the integration
period. The data is
|
|
13+nv+3
|
Comment 4
|
recorded at 30 seconds, the values reported are for 90
seconds signal
|
|
13+nv+4
|
Comment 5
|
integration periods. Calibration uncertainty (accuracy)
is estimated to be
|
|
13+nv+5
|
Comment 6
|
approximately +/- 15% for [NO], +/-18% for [NO2], and
+/-20% for [NOy] at the
|
|
13+nv+6
|
Comment 7
|
95% confidence limit and should be treated as a random
additive error term.
|
|
13+nv+7
|
Comment 8
|
Sigma values represent measurement precision estimates
based on photon
|
|
13+nv+8
|
Comment 9
|
95% confidence limit and should be treated as a random
additive error term.
|
|
13+nv+nc-1
|
Comment nc
|
COMMENT CODE 12 = Lower limit estimate based on [NO] LOD
value
|
|
13+nv+nc or nh + 1
|
Data Rec 1
|
265, 63463, 114, 7, 49.2, 15.2, 1220, 46, -999.9, -999.9,
-999.9, -999.9, -999.9, -999.9, 0, 0, 0
|
|
nh + 2
|
Data Rec 2
|
265, 63553, 126, 7.3, -888.8, -888.8, 1160, 45, -999.9,
-999.9, 35.8, 17.9, -999.9, -999.9, 0, 2, 0,
|
|
nh +3
|
Data Rec3
|
265, 63643, 132, 7.7, -888.8, -888.8, 1340, 50, -999.9,
-999.9, 37.2, 18.6, -999.9, -999.9, 0, 2, 0,
|
FIGURE 2 : Header Sample Description 2 Standard
Grab Sample : Start/Stop/Midpoint Time
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
30
|
|
2
|
FileName
|
NHAG1D03.TRA
|
|
3
|
Experimenter name, Instit.
|
Talbot , Robert , University of New Hampshire
|
|
4
|
Species
|
ACIDIC TRACE GASES/MIST CHAMBER
|
|
5
|
Expedition
|
TRACE-A
|
|
6
|
Flt Date, Rev Date
|
92, 9 , 21, 93, 4, 30
|
|
7
|
NF
|
3
|
|
8
|
NV
|
7
|
|
9
|
NC
|
11
|
|
10
|
DT
|
2
|
|
11
|
Avg Period
|
0
|
|
12
|
Samp Freq
|
0
|
|
13
|
Var(1)
|
Day, Julian (GMT), 1, 0, 265, 265, -999 ,0
|
|
13+1
|
Var(2)
|
Start Time, Sec (GMT), 1, 0, 56490, 72450, -999, 0
|
|
13+2
|
Var(3)
|
Stop Time, Sec (GMT), 1, 0, 57303 ,72935, -999, 0
|
|
13+3
|
Var(4)
|
Sample Midpoint, Sec (GMT), 1, 0, 56897 ,72693, -999 ,0
|
|
13+4
|
Var(5)
|
HNO3, pptv , 1, 0 ,26, 195, -999, 2 -888, 5, -777, -999
|
|
13+5
|
Var(6)
|
HCOOH, pptv, 1 , 0,649, 2668, -99, 2 ,-88, 10 , -77, -99
|
|
13+nv-1
|
Var(nv)
|
CH3COOH, pptv, 1, 0 ,202, 649, -99, 2, -888, 15, -777,
-999
|
|
13+nv
|
Comment 1
|
ACIDIC GAS DATA ARE STATED IN MIXING RATIOS (MOLAR RATIO
IN
|
|
Comment 2
|
PARTS PER TRILLION BY VOLUME, PPTV). MIXING RATIOS BELOW
THE
|
|
|
LIMIT OF DETECTION ARE INDICATED AS -888. ESTIMATED MEAN
DETECTION
|
|
|
LIMITS ARE AS FOLLOWS: 5 pptv HNO3, 10 pptv HCOOH, 15
pptv CH3COOH
|
|
|
OVERALL UNCERTAINTY IN MIXING RATIOS ARE ñ15-20%
for HNO3;
|
|
|
ñ15% FOR HCOOH AND; ñ20% FOR CH3COOH
|
|
|
CAUTION: DO NOT USE THESE DATA ON TIME SCALES SHORTER
THAN
|
|
|
THOSE REPORTED HERE. DIRECT INQUIRES ABOUT THESE DATA
TO:
|
|
|
ROBERT W. TALBOT, INSTITUTE FOR THE STUDY OF EARTH, OCEANS
AND
|
|
|
SPACE, MORSE HALL, UNIVERISTY OF NEW HAMPSHIRE, DURHAM,
NH 03824.
|
|
13+nv+nc-1
|
Comment nc
|
PHONE: 603-862-1546, FAX: 603-862-0188, E-MAIL: R_TALBOT@UNHH.UNH.EDU
|
|
13+nv+nc
|
Data Rec 1
|
265, 56490, 57303, 56897, -888, 649, 280
|
|
Data Rec 2
|
265, 57569, 58410, 57990, 46, 776, 381
|
Figure 3: Header Sample Description 3 Vertical
Column Sample : Variable Number Sampling Points (DIAL
Datasets, etc.)
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
27
|
|
2
|
FileName
|
BEAZD03.TRA
|
|
3
|
Experimenter name, Instit.
|
Browell, Dr. Edward V., NASA Langley Research Center
|
|
4
|
Species
|
DC-8 IR Zenith Aerosol Relative Backscatter
|
|
5
|
Expedition
|
GTE/TRACE A
|
|
6
|
Flt Date, Rev Date
|
92, 9, 21, 93, 6, 4
|
|
7
|
NF
|
3
|
|
8
|
NV
|
9 (NOTE: This dataset type has NV-1 regular variables,
and one array variable. The array variable is dimensioned
by variable NV-1)
|
|
9
|
NC
|
6
|
|
10
|
DT
|
3
|
|
11
|
Avg Period
|
0
|
|
12
|
Samp Freq
|
.0168 (Data recorded at 59.5 seconds)
|
|
13
|
Var(1)
|
Day, Julian (GMT), 1 ,0, 265, 266, -999, 0
|
|
13+1
|
Var(2)
|
Start Time, Sec (GMT), 1, 0, 67386, 86400, -999, 0
|
|
13+2
|
Var(3)
|
Geometric altitude of aircraft, (m), 1, 0, 9398, 12939,
-9999, 0
|
|
13+3
|
Var(4)
|
Geometric altitude at which data begins, (m), 1, 0, 9998,12576,
-9999, 0
|
|
13+4
|
Var(5)
|
Altitude increment , (m), 1, 0,450, 450, -9999, 0
|
|
13+5
|
Var(6)
|
Latitude, ( +N degrees), .01, 0, -9000, 9000, -9999,0
|
|
13+6
|
Var(7)
|
Longitude, ( +E degrees),.01, 0, -18000, 18000, -99999,0
|
|
Var(nv-1)
|
Number of data values, #, 1, 0, 0, 100, -99,0
|
|
13+nv-1
|
Var(nv)
|
Relative aerosol backscatter profile, , 1, 0,-50000,50000,-99999,0
|
|
13+nv
|
Comment 1
|
Final Reduced Resolution Archive of IR Aerosol Lidar Data
-Vertical sampling interval is
|
|
Comment 2
|
450 meters. Horizontal sampling interval is 59.5 seconds
(approximately 14 kilometers).
|
|
Comment 3
|
Number of lines per reporting interval variable due to
nature of data. Number of data
|
|
Comment 4
|
points in profile located in variable NV-1 (Variable 8).
Read through variable 8, then read
|
|
13+nv+nc-1
|
Comment nc
|
variable 9 which is an array with 1 to (variable 8) elements.
|
|
13+nv+nc
|
Data Rec 1
|
265, 67386, 9397, 9997 , 450 , 2935 , -9342, 0
|
|
13+nh+1
|
Data Rec 2
|
265, 67454 , 9398, 9998, 450, 2934 , -9325, 44,
2052, 2547, 2580, 2511, 2340, 1804, 9494, 2580, 1625,
2602,
1775, 1809, 1789, 2864, 1853, 7281, 9107, 13225, 12607,
11518,
11493, 8504, 3184, 1067, 5842, 7404, 2391, 6119, -528,
66,
5435, 3422 , 927, -3807, -7678, -3190, -9880, 13053, -1852,
1109,
5371, -9696, 5140, -3300
|
|
15+nh+2
|
Data Rec 3
|
265, 67515, 9400, 10000, 450, 2934, -9310, 44,
2034, 2620, 2499, 2482, 2194, 2087, 17791, 2389, 1372,
2117,
1273, 2036, 2883, 1611, 3915, 5565, 7568, 11035, 9493,
14609,
7538, 7979, 7112, 6753, 8772, 4974, 6670, 3325, 2622,
2405,
2017, -113 , 3130, 2660, 5135, -7359, -1037, 5070, -3471,
3462,
12667, -1378, 17117, -5156
|
Figure 4: Header Sample Description 4 Vertical
Column Sample : Standard Sonde Data (Ozonesondes, Rawinsondes,
etc.)
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
31
|
|
2
|
FileName
|
FJACPS01.TRA
|
|
3
|
Experimenter name, Instit.
|
FISHMAN, J., NASA LaRC
|
|
4
|
Species
|
OZONE/ECC4 SONDE
|
|
5
|
Expedition
|
PRE-TRACE-A
|
|
6
|
Flt Date, Rev Date
|
90, 07, 28, 93, 05, 28
|
|
7
|
NF
|
1
|
|
8
|
NV
|
11
|
|
9
|
NC
|
8
|
|
10
|
DT
|
4
|
|
11
|
Avg Period
|
0
|
|
12
|
Samp Freq
|
0
|
|
13
|
Var(1)
|
Day, Julian (GMT), 1, 0, 209, 209, -999, 0
|
|
14
|
Var(2)
|
Start Time, Sec (GMT),1, 0, 67920, 74640, -999, 0
|
|
15
|
Var(3)
|
PRESSURE, (hPA) ,1, 0, 8.2, 1009.9,-999.9,0
|
|
16
|
Var(4)
|
ALTITUDE , (m) , 1, 0,91,32925,-9999,0
|
|
17
|
Var(5)
|
PARTIAL PRESSURE OZONE, (nb), 1, 0, 10.3, 151.8, -9.9,0
|
|
18
|
Var(6)
|
CUMULATIVE INTEGRATED OZONE ,(at-cm),1, 0, 0, .2248,-9.99999,0
|
|
19
|
Var(7)
|
TEMPERATURE , (deg K), 1, 0, 119.4, 297.5, -999.9, 0
|
|
20
|
Var(8)
|
OZONE NUMBERS DENSITY, , 1, 0, 3.6E11, 4.8E12 , -999.9,
0
|
|
21
|
Var(9)
|
DEW POINT TEMPERATURE , (deg K) , 1, 0, 195.8, 289.4,
-999.9, 0
|
|
22
|
Var(10)
|
OZONE, (ppbv), 1, 0, 35.87, 7904.73, -999.99, 0
|
|
23
|
Var(nv)
|
RELATIVE HUMIDITY, (%) , 1, 0, 13.14, 87.66, -999.99,
0
|
|
24
|
Comment 1
|
DATA REPORTED AT VARIABLE TIME INTERVALS. 47 PRE-
|
|
25
|
Comment 2
|
TRACE-A SONDES COVERING THE PERIOD OF JULY 1990 TO
|
|
26
|
Comment 3
|
AUGUST 1992 AND 20 SONDES DURING TRACE-A COVERING
|
|
27
|
Comment 4
|
THE PERIOD SEPTEMBER-OCTOBER 1992 ARE REPORTED.
|
|
28
|
Comment 5
|
67 TOTAL ECC4 SONDES LAUNCHED AT ASCENSION ISLAND.
|
|
29
|
Comment 6
|
LAT/LONG: 8 DEGREES SOUTH, 15 DEGREES WEST.
|
|
30
|
Comment 7
|
STATION HEIGHT: 91 METERS.
|
|
31
|
Comment nc
|
ECC4 SONDE SERIAL NUMBER:4A4685
|
|
32
|
Data Rec 1
|
209, 67920, 1009.9, 91, 36.2, 0.00000, 297.5, 8.8178E+11,
288.7, 35.87, 57.98
|
|
33
|
Data Rec 2
|
209, 67980, 969.0, 452, 35.0, 0.00116, 295.2, 8.5951E+11,
289.2, 36.15, 68.69
|
|
34
|
Data Rec 3
|
209, 68040, 931.0, 799, 34.8, 0.00227, 291.9, 8.6323E+11,
289.4, 37.37, 85.31
|
Figure 5: Header Sample Description 5 Gridded
Dataset (Fires Gridded data)
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
31
|
|
2
|
FileName
|
SABFTI09.TRA
|
|
3
|
Experimenter name, Instit.
|
FISHMAN, J., NASA LaRC
|
|
4
|
Species
|
WEEKLY TOTAL PIXEL FIRE COUNTS/AVHRR
|
|
5
|
Expedition
|
TRACE-A
|
|
6
|
Flt Date, Rev Date
|
92, 10, 30, 93, 06, 06,
|
|
7
|
NF
|
09
|
|
8
|
NV
|
11
|
|
9
|
NC
|
8
|
|
10
|
DT
|
5
|
|
11
|
Avg Period
|
0
|
|
12
|
Samp Freq
|
0
|
|
13
|
Var(1)
|
Start Day, Julian (GMT), 1, 0, 283, 283, -99, 0
|
|
13+1
|
Var(2)
|
Start Time, Seconds GMT, 1, 0, -99, -99, -99, 0
|
|
13+2
|
Var(3)
|
Stop Day, Julian (GMT), 1, 0,289, 289, -99, 0
|
|
13+3
|
Var(4)
|
Stop Time, Seconds GMT, 1, 0,-99, -99, -99,0
|
|
13+4
|
Var(5)
|
Start Latitude, Deg North, 1,0, -44.5, -44.5, -999.99,0
|
|
13+5
|
Var(6)
|
Start Longitude, Deg East, 1, 0,-89.75,-89.75,-999.99,0
|
|
13+6
|
Var(7)
|
Latitude Increment, Deg North, 1, 0, 0.5, 0.5, -999.9,
0
|
|
13+7
|
Var(8)
|
Longitude Increment, Deg East, 1, 0, 1.0, 1.0, -999.9,
0
|
|
Var(9)
|
Number of Rows of Latitude, #, 1, 0, 60, 60, -999, 0
|
|
Var(10)
|
Number of Columns of Longitude, #, 1, 0, 140, 140, -999,
0
|
|
13+nv-1
|
Var(nv)
|
Pixel Count, Number, 1, 0, -40, 521, -120., 0
|
|
13+nv
|
Comment 1
|
THIS DATA FILE OF, SATELLITE CHANNEL 3 AVHRR BASED, WEEKLY
TOTAL
|
|
Comment 2
|
PIXEL FIRE COUNTS ARE BASED ON DATA FROM OCTOBER 9-15,
1992.
|
|
13+nv+nc-1
|
Comment nc
|
READ "FIRECNT1.RME" for CAPABILITIES AND LIMITATIONS
|
|
13+nv+nc
|
Data Rec 1
|
283, -99, 289 , -99 , -44.5, -89.75, .5, 1.0, 60, 140,
|
|
13+nh+1
|
Data Rec 2
|
- 120., -120., -120., -120., -120., -120., -120., -120.,
-120., -120., -120., -120.,
- 120., -120., -120., -120., -120., -120., -120., -120.,
-120., -120., -120., -120.,
- 120., -120., -120., -120., -120., -120., -120., -120.,
-120., -120., -120., -120.,
- 120., -120., -120., -120., -120., -120., -120., -120.,
-120., -40., 8., -40.,
- 40., 2., 48., 1., 44., 132., 178., 70., 30., 33., 71.,
64.,
188., 1., 500., 121., 90., 43., 24., -40., 17., 479.,
37., 63.,
120., 115., 199., 217., 56., 46., 51., 24., 55., 107.,
41., 13.,
11., 28., 1., 3., 103., 92., 63., 35., 44., 67., 34.,
3.,
40., 6., -40., 5., 2., 2., 6., -40., -40., -40., -40.,
-40.,
- 40., -120., -120., -120., -120., -120., -120., -120.,
-120., -120., -120., -120.,
- 120., -120., -120., -120., -120., -120., -120., -120.,
-120., -120., -120., -120.,
- 120., -120., -120., -120., -120., -120., -120., -120.
|
Figure 6: Header Sample Description 6 Trajectory
Dataset (Isentropic and Isobaric Trajectory Data)
|
Record
|
Explanation
|
Sample Data Record
|
|
1
|
NH
|
26
|
|
2
|
FileName
|
MJ101d04.PWA
|
|
3
|
Experimenter name, Instit.
|
Merrill, John, University of Rhode Island
|
|
4
|
Species
|
Isentropic Air Mass Trajectory
|
|
5
|
Expedition
|
PEM West-A
|
|
6
|
Flt Date, Rev Date
|
91, 09, 16, 94,12,29
|
|
7
|
NF
|
4
|
|
8
|
NV
|
7
|
|
9
|
NC
|
7
|
|
10
|
DT
|
6
|
|
11
|
Avg Period
|
43200
|
|
12
|
Samp Freq
|
21
|
|
13
|
Var(1)
|
Day, Julian (GMT), 1, 0,259, 260, -999, 0
|
|
13+1
|
Var(2)
|
Time, Sec (GMT), 1, 0, 64740, 22883, -999, 0
|
|
13+2
|
Var(3)
|
Potential Temperature, Kelvin, 1, 0, 302, 343, -999, 0
|
|
13+3
|
Var(4)
|
Latitude, Degrees North, 1, 0, 14.2, 66.2, -99.9, 0
|
|
13+4
|
Var(5)
|
Longitude, Degrees East, 1, 0, -179.8, 179.7, -999.9,
0
|
|
13+5
|
Var(6)
|
Pressure, hPa (same as milibars), 1, 0, 213, 864, -999,
0
|
|
13+6
|
Var(7)
|
Height, meters above sea level, 1, 0, 1445, 11452, -9999,
0
|
|
13+nv
|
Comment 1
|
This and every trajectory is described in 21 data lines.
The first line
|
|
13+nv+1
|
Comment 2
|
is the trajectory end point, corresponding to a selected
aircraft time
|
|
13+nv+2
|
Comment 3
|
time and position. Each following line is the trajectory's
position
|
|
13+nv+3
|
Comment 4
|
on the previous time step. Time steps prior to the start
time are all
|
|
13+nv+nc-1
|
Comment nc
|
at 0000 and 1200 GMT. For each trajectory read 21 data
lines
|
|
13+nv+nc or nh + 1
|
Data Rec 1
|
259, 64740, 335, 42.4,-126.0, 285, 10076
*(NOTE: Time here is the actual time during the flight,
referred to as the trajectory end point)
|
|
nh + 2
|
Data Rec 2
|
259, 43200, 335, 43.1,-127.8, 279, 10217 *(NOTE: This
time is the next even increment of the Averaging Period
in Header Line 11)
|
|
nh + 3
|
Data Rec 3
|
259, 0, 335, 40.7,-131.7, 285, 10046
|
|
nh + 4
|
Data Rec 4
|
258, 43200, 335, 32.9,-134.1, 279, 10086
|
|
nh + 5
|
Data Rec 5
|
258, 0, 335, 24.1,-137.8, 330, 8991
|
|
nh + 6
|
Data Rec 6
|
257, 43200, 335, 20.1,-143.0, 411, 7358
|
|
nh + 7
|
Data Rec 7
|
257, 0, 335, 19.3,-146.6, 442, 6847
|
|
nh + 8
|
Data Rec 8
|
256, 43200, 335, 20.1,-150.5, 435, 6962
|
|
nh + 9
|
Data Rec 9
|
256, 0, 335, 22.1,-153.8, 422, 7205
|
|
nh + 21
|
Data Rec 21
|
250, 0, 335, 33.6,-145.2, 305, 9581
|
|
nh +22
|
Data Rec22
|
259, 67680, 334, 46.6,-131.5, 285, 10039 *(NOTE: This
record is the second
Trajectory End Point . 20 more data lines follow.)
|
V. FTP Protocol for GTE Data Exchange
DATA ARCHIVE MEMO: FTP File Transfer to/from the GTE Archives
The GTE Data Archive datasets are now located on ANONYMOUS FTP
site at ftp-gte.larc.nasa.gov
located at NASA Langley and accessible 24 hours a day. The GTE
Archive can also be accessed through the GTE Web site at http://www-gte.larc.nasa.gov
(Data Archive link). Type the quoted (" ") commands to
login and access the various on-line files. Note that you can now
submit your data files via FTP. Follow the instructions given below
to login and transfer files to/from the GTE Archives. NOTE: The
proprietary archives (those not yet released to the public) are "password" protected
from being read by the public. The protected data is accessible
to the science team only using FTP protocol. Contact us at the
E-mail address listed below for more information on accessing the
protected data.
LOGGING ON TO THE GTE ARCHIVE
1) Access via FTP the GTE Archives computer "ftp-gte.larc.nasa.gov".
If this name is not on your host table, address the computer using
the IP address of 128.155.54.94
2) Login using "anonymous" as your name.
3) Enter your actual E-mail address as your password. Note: your
E-mail address will be logged and used to distribute any updates
on the data that has been accessed.
4) "cd pub" to change directories to the public directory.
(UNIX is case sensitive - use lower case for all commands. Our
GTE main directories are in all caps, although subdirectories may
be in either.
LOCATING THE GTE ARCHIVE FILES YOU WISH TO TRANSFER TO YOUR
COMPUTER
5) Change to the directory of the GTE Expedition archive files
of interest. For example, "cd PEMWESTA" or "cd ABLE3A"
6) "ls" to list the files and/or sub-directories in
this directory. NOTE: The GTE Archives have the following long
directory structure:
ftp/pub/Expedition/Sub-category/Investigator.Institution/Species/Files
PLEASE NOTE: not all Expeditions have "Sub-categories" and
most Investigators do not have a "Species" sub-directory.
7) Assuming you changed directories to PEMWESTA, you can now change
to the subdirectory of interest. For example, "cd dc-8/heikes.uri" will
put you in the DC-8 aircraft subdirectory, and then to the investigator
heikes.uri subdirectory. You can now access files in that subdirectory.
FTP only allows you to retrieve files in one subdirectory at a
time, thus type "cd .." to return to the parent directory
if you desire to view the subdirectory containing files of another
investigator.
TRANSFER COPIES OF THE FILES TO YOUR COMPUTER
8) Select the local drive and directory on your machine to receive
the data. Useful commands:
"drive x:" to change the local drive to "x:"
"lcd xxxxx" to change the local directory to "xxxxx"
"ldir" to get a directory listing of the local drive
"help" to get a complete listing of the FTP commands
on your machine. Your actual commands may differ slightly from
these.
9) The command "mget *.*" will get all files in the
subdirectory.
10) "cd .." to transfer to the parent directory: return
to (7) to repeat the process
SENDING FILES TO THE GTE ARCHIVE USING FTP
To submit data to the Archive, you must have access to the "password" protected
FTP site. Again, please contact us at the E-mail address listed
below for more information to access this protected site. Assuming
you have successfully logged on to the FTP site:
11) Change directories to "incoming" (path = pub/incoming).
Useful change directory commands include: "cd .." to
change to the parent directory and "cd /" to change to
the root directory.
12) Change to the appropriate subdirectory: "cd TRACEA" to
send GTE TRACE-A files.
13) Create a subdirectory for your files if one does not already
exist. Use your name and institution to name the subdirectory.
For example, "mkdir bradshaw.git" will create a subdirectory
for files from the John Bradshaw investigation team of Georgia
Tech.
14) Use the commands of (8) to go to your local drive and directory
where the files to be transferred are stored.
15) Transfer the files to the "incoming" directory with
one of the following commands:
"put filename" To transfer one file from your machine
to "incoming". You will be prompted to enter the foreign
file name.
"mput *.*" To transfer all files in your host directory
and keep same names.
"mput gt*.* To transfer all files beginning with "gt" in
your host directory.
16) Log off the system. "quit"
17) Contact the GTE Data Manager (use E-mail if possible) and
describe the action you have taken. Provide a list of files transferred
and the directory path on the FTP site that was used:
GTE Data Manager
email: gte+archive@larc.nasa.gov
phone: (757)864-4838
fax: (757)864-5841
*** END OF INFO ON FTP TRANSFER ***
GTEScan Software
All GTE data files must comply with GTE Format standards. PIs
are encouraged to run GTEScan on their files prior to submitting
them to the GTE Archive.
Download:
Download GTEScan.exe and GTEScan.hlp to your hard drive from the "password" protected
FTP site. GTEScan runs in Win32 environment (Win95/98/NT/2000).
Usage:
This version scans GTE formatted files for data type 0, 1, 2,
3, and 4 -- it verifies data files as follows:
1) File Header for compliance with the GTE Format 2) Time Logic
and continuity 3) Min Max checking 4) LOD Logic
Simply run GTEScan, select Open (1 or multi files)..., and program
takes over. If no major errors found, GTEScan finds the actual
Mins, Maxs; the correct codes for missing data and LODs; and by
default, re-generates the file(s) to a directory "...\Output.gte\".
Help:
See "Topics" under Help menu item.
TABLE 1. Principal Investigator Codes
| Invesitigator |
Institution |
Code |
|
AKIMOTO, H.
|
Nat. Inst. for Environmental Studies
|
AH
|
|
ANDERSON, B. E.
|
NASA Langley Research Center
|
AB
|
|
ANDREAE, M. O.
|
Max Planck Institute for Chemistry
|
MA
|
|
ARIMOTO, R.
|
Univ. of Rhode Island
|
AR
|
|
APEL, E.
|
NCAR
|
AP
|
|
ATLAS, E.
|
NCAR
|
EA
|
|
AVERY, M.
|
NASA Langley Research Center
|
AM
|
|
BANDY, A. R.,THORNTON, D.
|
Drexel University
|
DU
|
|
BARRICK, J. D. W.
|
NASA Langley Research Center
|
PO
|
|
BODECKER, G.
|
NIWA
|
BG
|
|
BLAKE, D. UC-Irvine
|
U CA - Irvine
|
UC
|
|
BRADSHAW, J.
|
Georgia Inst. Of Technology
|
BJ
|
|
BROWELL, E. V.
|
NASA Langley Research Center
|
BE
|
|
BRUNE, W.
|
Penn State University
|
BW
|
|
CANTRELL, C
|
NCAR
|
CC
|
|
CARMICHAEL, G. R.
|
University of Iowa
|
UI
|
|
CARROLL, M.A.
|
University of Michigan
|
MC
|
|
CHAMEIDES, W. L.
|
Georgia Inst. of Technology
|
CW
|
|
CHATFIELD, R.
|
NASA Ames Research Center
|
CR
|
|
CLARKE, T.
|
University of Hawaii
|
TC
|
|
DAVIS, D.
|
Georgia Inst. of Technology
|
DD
|
|
EISELE, F.
|
Georgia Inst. of Technology
|
FE
|
|
FEICHTER, J
|
Germany
|
JF
|
|
FISHMAN, J.
|
NASA Langley Research Center
|
FJ
|
|
FITZGARRALD, D.
|
SUNY
|
SU
|
|
FLOCKE, F.
|
NCAR
|
FF
|
|
FRIED, A.
|
NCAR
|
FA
|
|
FUELBERG, H.
|
Florida State University
|
FS
|
|
GARSTANG, M.
|
Simpson Weather Associates
|
MG
|
|
GREGORY, G. L.
|
NASA Langley Research Center
|
GG
|
|
GTE PROJECT OFFICE
|
NASA Langley Research Center
|
PO
|
|
HEIKES, B.
|
Univ. of Rhode Island
|
HB
|
|
HUEBERT, B
|
University of Hawaii
|
HU
|
|
JACOB, D.
|
Harvard
|
DJ
|
|
JAFFEE, D.
|
Univ. of Alaska
|
JD
|
|
KELLY, K.
|
NOAA Aeronomy Lab.
|
KK
|
|
KIRCHHOFF, V.
|
INPE
|
KV
|
|
KITADA, T.
|
Toyohashi University, Japan
|
TU
|
|
KOIKE, M.
|
Nagoya University, Japan
|
KM
|
|
KONDO, Y.
|
Nagoya University, Japan
|
NG
|
|
LAM, K. S.
|
Hong Kong Polytechnic
|
HK
|
|
LENSCHOW, D.
|
NCAR
|
DL
|
|
LIU, C. M.
|
National Taiwan University
|
LM
|
|
LIU, S. C., McKEEN, S.
|
NOAA Aeronomy Lab.
|
LS
|
|
MERRILL, J.
|
Univ. of Rhode Island
|
MJ
|
|
MISSION MANAGER LOGS
|
NASA Ames Research Center
|
MM
|
|
NEWELL, R.
|
MIT
|
NR
|
|
NGANGA, D.
|
University of Ngouabi
|
UN
|
|
NOBRE, C.
|
INPE
|
NC
|
|
NORDEMANN, D.
|
INPE
|
DN
|
|
OLTMANS, S.
|
NOAA
|
SO
|
|
PARK, J. K.
|
Korean Inst. of Science and Tech.
|
KI
|
|
PRATHER, M.
|
U CA - Irvine
|
PM
|
|
PROSPERO, J. M.
|
Univ. Miami
|
UM
|
|
PUESCHEL, R.
|
NASA Ames Research Center
|
PR
|
|
RASSMUSSEN, R.
|
Oregon Graduate School
|
RR
|
|
RIDLEY, B.
|
NCAR
|
NR
|
|
RIEMERR. R
|
NCAR
|
RD
|
|
RITTER, J.
|
NASA Langley Research Center
|
TM
|
|
RODGERS, M.
|
Georgia Institute of Technology
|
RM
|
|
RODRIGUEZ, J.
|
Atmos. & Environ. Research, Inc.
|
RJ
|
|
ROWLAND, F. S., BLAKE, D.
|
Univ. California - Irvine (UCI)
|
UC
|
|
SACHSE, G. W.
|
NASA Langley Research Center
|
SG
|
|
SANDHOLM, S.
|
GA Tech.
|
SS
|
|
SAKAMAKI, F.
|
Nat. Inst. for Environmental Studies, Japan
|
SF
|
|
SETZER, A.
|
INPE
|
SA
|
|
SHETTER, R.
|
NCAR
|
RS
|
|
SINGH, H. B.
|
NASA Ames Research Center
|
SH
|
|
TALBOT, R. W.
|
University of New Hampshire
|
NH
|
|
THOMPSON, A.
|
NASA Goddard Space Flight Center
|
AT
|
|
TORRES, A.
|
NASA Wallops Flight Facility
|
TA
|
|
TREPTE, C.
|
NASA Langley Research Center
|
TC
|
|
WEBER, R.
|
GA Tech.
|
WR
|
|
WOFSY, S.
|
Harvard University
|
SW, HU
|
|
ZHOU, X.
|
Academy of Meteorological Science Peoples Republic of
China
|
AM
|
|
ZIMMERMAN, P.
|
NCAR
|
ZP
|
TABLE 2. GTE Expedition Codes
|
GTE Expedition
|
Expedition Location
|
3-Digit Code
|
|
CITE 1 1983
|
Wallops Island, VA
|
CTW
|
|
CITE 1 1983
|
Hawaii
|
CTH
|
|
CITE 1 1984
|
Eastern North Pacific---off the California coast
|
CTA
|
|
ABLE 1 1984
|
Barbados, French Guyana
|
AB1
|
|
ABLE 2A 1985
|
Amazon Basin
|
A2A
|
|
CITE 2 1986
|
Western USA
|
CT2
|
|
ABLE 2B 1987
|
Amazon Basin
|
A2B
|
|
ABLE 3A 1988
|
Alaska---Barrow, Bethel
|
A3A
|
|
CITE 3 1989
|
Western North Atlantic - off Virginia Coast Western South
Atlantic - off Brazil coast
|
CT3
|
|
ABLE 3B 1990
|
North Bay, Ontario - Goose Bay, Labrador
|
A3B
|
|
PEM-West A 1991
|
Western North Pacific Rim
|
PWA
|
|
TRACE A 1992
|
Brazil, South Atlantic, southwest Africa
|
TRA
|
|
PEM-West B 1994
|
Western North Pacific Rim
|
PWB
|
|
PEM Tropics A 1996
|
South Pacific
|
PMT
|
|
PEM Tropics B 1999
|
South Pacific
|
PMB
|
|
TRACE P 2001
|
Western Pacific - Japan, Hong Kong
|
TRP
|
|
|
|
|
