National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce Customer Services Branch Mailing and physical

151 Patton Avenue

Room 468

Asheville North Carolina 28801-5001 USA 828-271-4800 828-271-4010 828-271-4876 ncdc.orders@noaa.gov 8:00 - 6:00 Eastern http://www.ncdc.noaa.gov/oa/about/ncdccontacts.html Unknown tabular digital data http://www.ncdc.noaa.gov Satellite Coastal Zone Color Scanner (CZCS) is historical digital data set DS-3620, archived at the National Climatic Data Center (NCDC). This is satellite data.CZCS was a multi-spectral line scanner devoted principally to measurements of ocean color, developed by NASA to measure ocean color. It operated from November 2, 1978 to June 22, 1986 on the Nimbus-7 satellite. CZCS had six spectral bands (channels). Channels 1 through 4 were devoted to ocean color, each having a 20 nanometer bandwidth and centered at 443, 520, 550, and 670 nanometers. Channel 5 had a 100 nanometer bandwidth centered at 750 nanometers and had a dynamic range which was more suited to land; it sensed solar radiance. Channel 6 operated in the 10.5 to 12.5 micrometer range and sensed emitted thermal radiance for derivation of equivalent black body temperature. Data were originally stored at NASA Goddard Space Flight Center.For most regions of the world, the color of the ocean is determined primarily by the abundance of phytoplankton and their associated photosynthetic pigments. As the concentration of phytoplankton pigments increases, ocean color shifts from blue to green. CZCS was a means of determining chlorophyll concentrations and the distributions of particular matter and dissolved substances.The purpose of the CZCS on Nimbus-7 was to obtain a better understanding of the temporal and spatial distribution of phytoplankton biomass and primary production, and a better understanding of the processes regulating the growth of phytoplankton and of the process influencing the ultimate fate of this organically fixed carbon. Satellite observations of ocean color were necessary to provide reliable estimates of marine phytoplankton biomass onsynoptic scales which are useful in studies of phytoplankton processes. The mission objectives for the CZCS were to obtain observations of ocean color and temperature, particularly in the coastal zones, which would provide data with sufficient spatial and spectral resolution for the following applications:-Measure concentrations of chlorophyll-a and phaeophytin.-Map biologically productive areas.-Map suspended sediment distribution and determine the type of materials suspended in the water.-Map Gelbstoff (dissolved yellow organic matter) as an indicator of salinity. -Detect pollutants in the upper level of the oceans.-Map temperature of coastal waters and the open ocean.-Study the interactions between coastal effluents and open waters. To make a wide range of climatic data available to researchers and the public. data set C00547 CZCS > Coastal Zone Color Scanner DOC/NOAA/NESDIS/NCDC For further details on the CZCS sensor and the Nimbus 7 satellite, please consult The Coastal Zone Color Scanner Instrument Guide,(http://eosdata.gsfc.nasa.gov/SENSOR_DOCS/CZCS_Sensor.html)and the Nimbus 7 Platform Guide, (http://podaac-www.jpl.nasa.gov:2031/SOURCE_DOCS/nimbus7.html).CZCS Sensor Guide Document, prepared by the Distributed Active Archive Center, NASA Goddard Space Flight Center, Greenbelt, Maryland, 1995.Ocean Color From Space, Prepared by the US Global Ocean Flux Study Office with contributions from NASA Goddard Space Flight Center, Woods Hole Oceanographic Institution, the University of Miami and the University of Rhode Island. HTML version published by the Distributed Active Archive Center, NASA Goddard Space Flight Center, Greenbelt, Maryland, 1995.The Living Ocean: Observing Ocean Color From Space, NASA Publication PAM-554, Goddard Space Flight Center, Greenbelt, Maryland, 1993.Coastal zone color scanner system calibration: A retrospective examination. R.H. Evans and H.R. Gordon, Journal of Geophysical Research, Vol.99. No. C4, pages 7293-7307, April 15, 1994.Coastal Zone Color Scanner, European Space Research Institute, Frascati, Italy.Nimbus 7 Coastal Zone Color Scanner (CZCS) Level 1 Data Product Users Guide NASA TM 86203, S.P. Williams, E.F. Szajna and W.A. Hovis. Goddard Space Flight Center, Greenbelt, MD 20771. July, 1986, 53 pages. 19781102 19860622 Ground Condition Complete As Needed -180.0 180.0 90.0 -90.0 DIF Discipline Keyword Thesaurus Earth Sciences > Atmosphere > Meteorology Earth Sciences > Atmosphere > Climatology Earth Sciences > Atmosphere > Weather Earth Sciences > Ocean > Oceanography ISO 19115 Topic Category ClimatologyMeteorologyAtmosphere 004 Elevation 006 Environment 007 Oceans 014 GCMD Sciences Keyword Valids EARTH SCIENCE > Oceans > Ocean Temperature > Sea Surface Temperature EARTH SCIENCE > Oceans > Ocean Optics > Gelbstoff EARTH SCIENCE > Oceans > Ocean Optics > Ocean Color EARTH SCIENCE > Oceans > Ocean Optics > Water-leaving Radiance EARTH SCIENCE > Oceans > Ocean Optics > Reflectance GCMD Location Valids Global Ocean GCMD Location Valids Sea surface None None Not provided Unknown Completeness information not available. Unknown Unknown The original Level 1 CZCS data were produced and stored on 9-track magnetic tape in Calibrated Radiance and Temperature Tape (CRTT) format. In this original format, two files were created per scene: an EBCDIC header describing the data, and a data file containing the instrument scans. When these data were transferred onto digital optical disks, the files in CRTT Tape format were modified slightly to create files in CRTT Archive format. A major change was the combining of the separate files into one file and adding a format header block. The Level 1 files archived and distributed by the Goddard DAAC are in this CRTT Archive format. The CRTT Tape format has been retained for the most part. See the Nimbus-7 Coastal Zone Color Scanner Level 1 Data Product Users Guide (NASA TM 86203) for a complete description of the original CRTT Tape format. The added format header block is the first 512 byte block in the file. This block was written on a VAX prior to being written on the platters. The files were then archived into the GSFC DAAC directly off of the optical platters. The header block contains 16-bit (2 byte) integers which only the first 16 are useful. Because the VAX writes to memory in Little Endian order, if you are on a machine which uses Big Endian order, you will have to swap the order of the bytes of the integers. Little Endian byte order puts the byte at the least significant positions in the word (the little end). Big Endian byte order puts the byte at the most significant position in the word (the big end). The DEC PDP-11/VAX and Intel 80x86 follow the Little Endian model, while the IBM 360/370 and Motorola 680x0, and others follow the Big Endian model. The byte swapping only applies to these first 16 integers of the header block. These bytes contain information on the format of the file. In the following description, each HEADER refers to a two byte integer: HEADER( 1) magic to signal archive header recordHEADER( 2) magic to signal archive header recordHEADER( 3) Length of data record (bytes)HEADER( 4) Number of documentation records (2 normally)HEADER( 5) First data record offset (blocks)HEADER( 6) Type code (101=CZCS)HEADER( 7) Number of data records (1-970)HEADER( 8) Orbit numberHEADER( 9) Year of passHEADER(10) Header record offset (blocks)HEADER(11) Header record length (bytes)HEADER(12) Documentation record length (bytes)HEADER(13) --HEADER(14) --HEADER(15) --HEADER(16) Scanner tilt (*100)An example of the first 512 byte block from a CZCS level 1 file is (this was done on an SGI IRIX with the Unix octal dump command: od -x 79005164931.ni7 .):0000000 aaaa aaaa ec31 0200 1000 6500 d802 f7030000016 bb07 0200 7602 d014 0000 0000 0000 58020000032 0000 0000 0000 0000 0000 0000 0000 0000*0001000The variables translate to: swapped hex bytes decimal comments --- ----- ------- --------HEADER( 1) = aaaa aaaa 43690 magic number HEADER( 2) = aaaa aaaa 43690 magic numberHEADER( 3) = ec31 31ec 12780 Length of record (bytes)HEADER( 4) = 0200 0002 2 Number of documentation recordsHEADER( 5) = 1000 0010 16 First data record offset (blocks)HEADER( 6) = 6500 0065 101 type code (101=czcs)HEADER( 7) = d802 02d8 728 number of recordsHEADER( 8) = f703 03f7 1015 orbit numberHEADER( 9) = bb07 07bb 1979 yearHEADER(10) = 0200 0002 2 header record offset (blocks)HEADER(11) = 7602 0276 630 header record length (bytes)HEADER(12) = d014 14d0 5328 documentation record length (bytes)HEADER(13) = 0000 0000 0 ---HEADER(14) = 0000 0000 0 ---HEADER(15) = 0000 0000 0 ---HEADER(16) = 5802 0258 600 scanner tilt (*100)From this example the layout of the file is:bytes comment----- -------0-31 File description.1024-1654 Header information. Start at HEADER(10) and is HEADER(11) length. This information is EBCDIC.2048-7376 Documentation record. Start at next block and is HEADER(12) length.8192-20972 First record. Start at HEADER(5) and is HEADER(3) length.20992-33772 Next record. Start at next 512 byte block and HEADER(3) length. Continue for a total of HEADER(7) records.9326592-9332224 The trailing documentation record. The last 304 bytes are null characters. This file is padded out to be an even multiple of 512 to keep integrity of the 512 byte blocks.Level 1 data contain at-spacecraft raw radiance counts with calibration and Earth location information appended, but not applied. Visible and infrared radiances were measured in six spectral channels. The spectral region and band widths of the six channels and primary use of each are indicated in the following table: Channel Spectral Band Primary purpose (micrometers)1 0.433 - 0.453 Chlorophyll absorption2 0.510 - 0.530 Chlorophyll correlation3 0.540 - 0.560 Yellow substance (Gelbstoff)4 0.660 - 0.680 Aerosol correction5 0.700 - 0.800 Land/cloud flag6 10.5 - 12.5 Surface temperature; failed shortly after launchUnit of Measurement:Level 1 Calibrated radiances were measured in units of mW/(cm2.sr.micron) with 1 km x 1km resolution Data Source: CZCS was flown aboard the Nimbus-7 satellite. None National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce Customer Service Mailing and physical

151 Patton Avenue

Room 120

Asheville North Carolina 28801-5001 USA 828-271-4800 828-271-4876 NCDC.Orders@noaa.gov DS-3620 Disclaimer: While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty. 20040722 20040722 National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce Customer Service Mailing and physical

151 Patton Avenue

Room 120

Asheville North Carolina 28801-5001 USA 828-271-4800 828-271-4876 NCDC.Orders@noaa.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998