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LBA-ECO CD-07 GOES-8 L1 RADIANCE DATA FOR AMAZONIA: 1998-2001
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Summary:

The LBA-ECO CD-07 team collected GOES-8 imager data over the LBA-ECO study region as part of our effort to characterize the incoming radiation and precipitation rates at regional scales. This data set contains data from all five imager channels at half-hourly or 3-hourly temporal resolution and 8-km/30-min spatial resolutions. The data cover the time period of March 1998 to February 2001.

Five wavelength regions of radiation data from the visible to the infrared are available at half hourly to 3 hourly intervals daily from March 1998 to February 2001 for the area known as Amazonia, geographically from about 5 N - 16 S latitude and 40 W - 75 W longitude in South America. This is the Amazon watershed area primarily. The dominant land cover in the western part is rain forest, with large patches of pasture in Bolivia, Peru, and Colombia. The central part of the area is mainly rain forest with scattered pastures and interrupted forests. The southeastern quadrant is mostly cleared.

The data were collected by the University of Florida team under LBA contract CD-07. Their objectives were to do the following:

These data are being provided in support of the LBA-Ecology program and are intended for scientists who know how to work with this type of data. Please read the references provided to find out more about this research.

The data set consists of approximately 92,000 binary image data files. There is one data file per date, time, and band. Please use the convenient subsetting tool provided in the ORNL DAAC Search and Order system for selecting data files based on band, time frame, and image quality values. A companion file with additional detailed information about the GOES-8 imager, data collection and processing is also provided [ CD07_L1_GOES_Image_readme.pdf].

Acknowledgement. The data files and several supporting documents were obtained from EOS-EarthData, the University of New HampshirE"S Earth Science Information Partner[http://eos-earthdata.sr.unh.edu/ ]. The EOS-EarthData Staff had organized, indexed, and documented the thousands of image files. The ORNL DAAC acknowledges their contribution in archiving this data.

Data Citation:

Cite this data set as follows:

Gu J. J., E. A. Smith, and H. J. Cooper. 2006. LBA-ECO CD-07 GOES-8 L1 Radiance Data for Amazonia: 1998-2001. Data set. Available on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/833.

Implementation of the LBA Data and Publication Policy by Data Users:

The LBA Data and Publication Policy [ http://daac.ornl.gov/LBA/lba_data_policy.html ] is in effect for a period of five (5) years from the date of archiving and should be followed by data users who have obtained LBA data sets from the ORNL DAAC. Users who download LBA data in the five years after data have been archived must contact the investigators who collected the data, per provisions 6 and 7 in the Policy.

This data set was archived in May of 2006. Users who download the data between May 2006 and April 2011 must comply with the LBA Data and Publication Policy.

Data users should use the Investigator contact information in this document to communicate with the data provider. Alternatively, the LBA Web Site [ http://lba.inpa.gov.br/lba/ ] in Brazil will have current contact information.

Data users should use the Data Set Citation and other applicable references provided in this document to acknowledge use of the data.

Table of Contents:

1. Data Set Overview:

Project: LBA (Large-Scale Biosphere-Atmosphere Experiment in the Amazon)

LBA Science Component: Carbon Dynamics

Team ID: CD-07 (Smith / Cooper / Dias)

The investigators were Smith, Eric A.; Dias, Pedro Leite da Silva; Cooper, Harry J.; Grose, Andy; Gu, Jiujing and Norman, John M.

You may contact Jiujing Gu (jgu@met.fsu.edu) for additional information.

LBA Data Set Inventory ID: CD07_GOES_L1_Radiance

For LBA-ECO, the Geostationary Operational Environmental Satellite 8 (GOES-8) imagery, along with the other remotely sensed images, were collected in order to provide spatially extensive information over the primary study areas at varying spatial scales.

Objective/Purpose

The primary objective for acquiring the GOES-8 images was to collect visible, infrared (IR), and water-vapor channel data covering the LBA-ECO study region at a sufficiently high temporal frequency for subsequent use in analyzing weather events and deriving temporal surface radiation parameters and patterns.

Related Data Sets: LBA-ECO CD-07 GOES-8 L3 Gridded Surface Radiation and Rain Rate for Amazonia: 1999

2. Data Characteristics:

Spatial Coverage:

            01-Mar-1998 to 16-Jun-1998               16-June-1998 to 28-Feb-2001
               Latitude    Longitude                   Latitude    Longitude      
          ----------  -----------                 ----------  -----------
Northwest      5 N         75 W                       5 N         75 W
Northeast      5 N         40 W                       5 N         40 W
Southwest     15 S         75 W                      16 S         75 W
Southeast     15 S         40 W                      16 S         40 W

Spatial Coverage Map:

Not available at this time.

Spatial Resolution:

Channel 1(VIS):  1 km
Channel 2(IR2):  4 km
Channel 3(IR3):  8 km
Channel 4(IR4):  4 km
Channel 5(IR5):  4 km

Projection:

The data is in GOES perfect projection. Although the GOES satellite is geostationary and in 'perfect' projection, it was repositioned during the course of this project Due to this satellite repositioning, there are three sets of Latitude-Longitude files. More information about the Latitude-Longitude files is provided in the data formats section.

Grid Description:

Not available at this revision.

Temporal Characteristics:

Temporal Coverage:

The dataset provides covers the period of Mar. 1998 to Feb. 2001.

Temporal Resolution:

There are five gridded datasets for each time period, one per spectral band. Our temporal coverage begins in March 1998, and extends to Feb 28, 2001.

There are two intensive archiving periods each year. One is from March 1 to April 30 (wet season); while the other is from August 1 to September 30 (dry season). During these intensive archiving periods, images are acquired every half hour or every hour. Outside these intensive periods, images are acquired every three hours; at 2:45,5:45, 8:45, 11:45, 14:45, 17:45, 20:45, and 23:45 UTC.

Data Range:

The GOES 8 satellite has five spectral bands as shown.

Band

Spectral Region

Wavelength
(micrometers)

File Size

1

Visible

0.65 (0.52 - 0.72)

14 MB

2

Near infrared window

3.9 (3.78 - 4.03)

1 MB

3

6.7 micron water vapor

6.7 (6.47 - 7.02)

0.5 MB

4

Thermal infrared window (clean)

11.0 (10.2 - 11.2)

1 MB

5

Thermal infrared window (dirty)

12.0 (11.5 - 12.5)

1 MB

Data Format(s):

GOES Binary Data

GOES-8 data files are BINARY swath data written in FORTRAN unformatted mode. Swath data is recorded in the binary files in repeatable numbers of columns and rows as the instrument "scans". The latitude/longitude readings of the pixels are not regular and a lat-lon array must accompany the GOES-8 reflectance data. The reflectance data are two-byte integers in the range 0-255 and the lat-lon array data are real numbers stored binary, 4 bytes per value. Latitude is from approximately 5N to 16S and the longitude is from approximately 75W to 40W.

Download companion files to assist in reading the GOES-8 data. There is a FORTRAN (rdboth.f) program and an IDL program (readgoes.pro) available to read the data. These programs use the data files and the latitude-longitude files as inputs. Additional information is provided within these programs. A FORTRAN / IDL compiler would be needed to execute these programs. Please change the appropriate reference paths to the data file and the latitude-longitude binary file to run these programs.

Data dimensions and format:

Start Time       End Time       Band       Bits       Lines        Pixels
-----------     ----------    --------    -------    --------    ---------
01-Mar-1998    16-Jun-1998     visible       8         2192         6200
 00:45 GMT       17:15 GMT       IR2         8          548         1550
                                 IR3         8          274         1550
                                 IR4         8          548         1550
                                 IR5         8          548         1550
02-May-1996    21-Oct-1996     visible       8         2296         6200
 17:45 GMT       23:45 GM        IR2         8          574         1550
                                 IR3         8          287         1550
                                 IR4         8          574         1550
                                 IR5         8          574         1550

A file of raw GOES-8 imagery contains a header record followed by visible, IR2, IR3, IR4, or IR5 data. The easiest way to distinguish between the file types is by the file name extension.  Another way is through the size of the file.  The information contained in bytes 1 to 4 of the header record should also contain the channel number information (see details below).  However, because of an error in the FSU software, the channel number field in the header record for IR2, IR4, and IR5 images is the same.  Therefore, the only way to distinguish channel 2, 4, 5 images is through the file name extension. The multiple-byte numeric integer fields in the header are stored as low-order byte first. The decimal number fields are Institute of Electrical and Electronics Engineers (IEEE) 4-byte floating point values. The format and contents of the header record is:

 
Bytes      Description
-------    --------------------------------------------------
1 - 4      Band number (32-bit integer; low-order byte first)
           (0 == visible; 1 == IR2; 2 == IR3, 1 == IR4; 1 == IR5)
           (Note that because of an error in the FSU software, the band number
           field for IR2, IR4, and IR5 are the same.  Based on this and the fact
           that the files are the same physical size, they cannot be
           distinguished on tape.  Distinguish the files
           by reading the contents of a file sent by FSU that listed the files
           by type.) 
5 - 8      Number of Pixels (32-bit integer; low-order byte first).
9 - 12     Number of Lines (32-bit integer; low-order byte first).
13 - 16    Decimal latitude of the center of the image in decimal degrees            
17 - 20    Decimal longitude of the center of the image in decimal degrees. 
21 - 132   Contents are unknown at this time.
133 - 140  Portions of the date and time as shown below.
141 - 8150 Contents are unknown at this time.
 

Please Note: Some files will be named aaa991431145.vis instead of A991431145.VIS; for example. The aaa files have an additional array of quality indicators for each row in the swath after the reflectance values.

Latitude and Longitude Binary Data Files

Companion latitude and longitude files for the GOES bands and date ranges are described.

The GOES images are in swath format and the satellite is geostationary. Due to satellite repositioning, there are three sets of lat/lon files: one prior to June 17, 1998; one for June 17, 1998 through March 5, 1999; and one set for after March 5, 1999. Therefore, you will need certain lat-lon files, depending on the date of the data you download.

In addition to the spectral data, the latitude-longitude navigation data are binary files of floating point numbers corresponding in rows and columns to the size of the spectral data arrays.

Companion Latitude/Longitude Files
Use For Goes Data... Files File Size (unzipped) Use For Bands...
Before June 17, 1998 A981411145ir2.ltln.bin 6.6 MB GOES bands 2,4,5
A981411145ir3.ltln.bin 3.3 MB GOES band 3
A981411145vis.ltln.bin 106.2 MB GOES band 1
June 17, 1998 - March 5, 1999 A981681445ir3.ltln.bin 3.5 MB GOES band 3
A981681445ir4.ltln.bin 7.0 MB GOES bands 2,4,5
A981681445vis.ltln.bin 111.2 MB GOES band 1
After March 5, 1999 A990641945ir2.ltln.bin 7.0 MB GOES bands 2,4,5
A990641945ir3.ltln.bin 3.5 MB GOES bands 3
A990641945vis.ltln.bin 111.2 MB GOES band 1

Quality Code Tables for Visible Images

Visible band data have been assigned the following quality flags:

“g” for less than 5% bad lines

“m” for less than 20% and more than 5% bad lines

“b” for more than 20% bad lines blank for missing images

“blank” for missing images

The quality information obtained for the visible images was used to assign the quality label for the rest of the channels. For time periods of missing visible channel data - No quality information is provided.

The quality codes have been tabulated by date and time in individual HTML files named <Year><Month>.HTM (e.g., 199810.HTM).

A companion file containing the full set of visible band quality files is available for downloading (Visible_Quality_Availability.tar.gz).

Example quality and availability file:

October 1998 Amazon Visible Images

 

 

 Yr  JD    Date                  Hour(UTC)

                    10 11 12 13 14 15 16 17 18 19 20 21

 

 98 274   Oct  1

 98 275   Oct  2

 98 276   Oct  3

 98 277   Oct  4    gg  g gg gg gg gg b  gg gg gg gg gg  

 98 278   Oct  5    gg gg gg gg gg gg bm gg gg gg mg gg  

 98 279   Oct  6    gg gg gg gg gg gg bm gg gg gg gg gg  

 98 280   Oct  7    gg gm gg gg gg gg b  gg gg gg gm gg  

 98 281   Oct  8    gg mg gg mg gg gg    gg gg gg gm gg  

 

NB:   “g” for less than 5% bad lines

“m” for less than 20% and more than 5% bad lines

“b” for more than 20% bad lines blank for missing images

“blank” for missing images

 

Availability Code Tables for the IR Bands Images

The IR bands data files have been assigned the following flags:

“y” for file exist
“blank” for file missing
 

Please recall that the quality information obtained for the visible images was used to assign quality flags to the IR bands. For time periods of missing visible data there is no quality information for the IR bands.

The IR bands file availability information has been tabulated by date and time in individual HTML files named <Year><Month>.html (e.g., 199810.html).

A companion file containing the full set of IR bands image availability files is available for downloading (IR2_to_IR5_Availability.tar.gz).

Example quality and availability file:

October 98 Amazon Channel 2 Images

 

 

 Yr  JD    Date                                 Hour(UTC)

                   0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

 

 98 274   Oct  1

 98 275   Oct  2

 98 276   Oct  3

 98 277   Oct  4     yy yy y         y yy yy yy yy yy yy yy yy yy y  yy yy yy yy yy yy yy

 98 278   Oct  5   y yy yy y         y yy yy yy yy yy yy yy yy yy yy yy yy yy  y yy yy yy

 98 279   Oct  6   y yy yy y         y yy yy yy yy yy yy yy yy yy yy yy yy yy yy yy yy yy

 98 280   Oct  7   y yy yy yy        y yy yy yy yy yy yy yy yy yy y  yy yy yy yy yy yy yy

 98 281   Oct  8   y yy yy yy        y yy yy yy yy yy yy yy yy yy y  yy yy yy yy yy yy yy

 98 282   Oct  9   y yy yy yy        y yy yy yy yy yy yy yy yy yy y  yy yy yy yy yy yy yy

 98 283   Oct 10   y yy yy yy        y yy yy yy yy yy yy yy yy yy y  yy yy yy yy yy yy yy

 

NB:   “y” for file exist

“blank” for file missing

 

Site boundaries: (All latitude and longitude given in degrees and fractions)

Site (Region)

Westernmost Longitude

Easternmost Longitude

Northernmost Latitude

Southernmost Latitude

Geodetic Datum

Amazonia (Central South America)

-75.3

-37.9

5.1

-16.1

World Geodetic System, 1984 (WGS-84)

Time period:

Parameters measured include:

3. Data Application and Derivation:

The GOES-8 images provide a high temporal resolution data set that would be useful for monitoring radiation loading and cloud development and movement over the LBA region.

4. Quality Assessment:

Data Validation by Source:
Whatever the processing level, the geometric quality of the image depends on the accuracy of the viewing geometry.
Spectral errors could arise from image-wide signal-to-noise ratio, saturation, cross-talk, spikes, or response normalization caused by a change in gain.

Confidence Level/Accuracy Judgment:
Not given.

Measurement Error for Parameters:
Not given.

Additional Quality Assessments:
None given.

5. Data Acquisition Materials and Methods:

The SRB and precipitation data were created from raw GOES-8 imager data. The Imager data was obtained by Dr. Eric Smith at FSU using the FSU Direct Readout Ground System located in Tallahassee, FL.

The data collected in April and September of 1999 were used to calibrate the remote sensing algorithms, while the data collected in March and October of the same year were used for validation. Details of the validation can be found at Gu et al., 2002.

To ensure the continuity of the dataset, which is required by carbon modeling, interpolations in time or space have been carried out near sunrise/sunset when the solar zenith angle is larger than 84 degrees and the use of visible images and simplified radiative transfer are prone to larger errors. Interpolation in time has been used when the satellite images are missing. Information on missing images or image quality could be found from our holdings list or quality table.

There are navigation problems during the first half of March 1999. Many images from that period are visually navigated.

6. Data Access:

This data is available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) or the EOS Data Gateway.

Data Archive Center:

Contact for Data Center Access Information:

E-mail: uso@daac.ornl.gov
Telephone: +1 (865) 241-3952
FAX: +1 (865) 574-4665

7. References:

Menzel, W. P., and J. F. W. Purdom, 1994: Introducing GOES-I: The first of a new generation of geostationary operational environmental satellite.  Bull. Amer. Meteor. Soc., 75, 757-781.

Kelly, K.A. 1989: GOES I-M image navigation and registration and user Earth location. GOES I-M Operational Satellite Conf., Arlington, VA, US. Department of Commerce, NOAA, 154-167.

Rossow, W.B., C.L. Brest, and M. Roiter, 1996: International Satellite Cloud Climatology Project (ISCCP) New Radiance Calibrations. WMO/TD-No. 736. World Meteorological Organization.

Rossow, W.B., C.L. Brest, and M.D. Roiter, 1995:  International Satellite Cloud Climatology Project (ISCCP):  Update of radiance calibration report.  Technical Document, World Climate Research Programme (ICSU and WMO), Geneva, Switzerland, 76 pp.

Weinreb, M., M. Jamieson, N. Fulton, Y. Chen, J.X. Johnson, C. Smith, J. Bremer, and J. Baucom, 1997:  Operational Calibration of the Imagers and Sounders on the GOES-8 and -9 Satellites.  NOAA Technical Memorandum NESDIS 44.

Related Publications

Gu, J.J., E.A. Smith, H.J. Cooper, A. Grose, G.S. Liu, J.D. Merritt, M.J. Waterloo, A.C. de Araujo, A.D. Nobre, A.O. Manzi, J. Marengo, P.J. de Oliveira, C. von Randow, J. Norman, and P.S. Dias.: Modeling carbon sequestration over the large-scale Amazon basin, aided by satellite observations. Part I: Wet- and dry-season surface radiation budget flux and precipitation variability based on GOES retrievals