AVHRR_Pathfinder-NODC-L3C-v5.2 dataset Sheri Phillips DOC/NOAA/NESDIS/NODC > National Oceanographic Data Center, NESDIS, NOAA, U.S. Department of Commerce (301) 713-3280 x127 (301) 713-3302 SSMC3, 1315 East-West Highway, Mail Code E/OC1 Silver Spring MD 20910-3282 USA Sheri.Phillips@noaa.gov 10:00 - 18:00 EST pointOfContact 2019-09-16 ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for imagery and gridded data ISO 19115-2:2009(E) 3 column 8640 0.0417 row 4320 0.0417 vertical 1 area AVHRR Pathfinder Version 5.2 Level 3 Collated (L3C) Global 4km Sea Surface Temperature for 1981-2012 2012-12-07 publication Coral Reef Information System https://www.coris.noaa.gov/metadata/records/ISO/html/iso_avhrr_pathfinder_nodc_l3c_v5_2.html resourceProvider 6946 DOC/NOAA/NESDIS/NODC > National Oceanographic Data Center, NESDIS, NOAA, U.S. Department of Commerce 1315 East West Highway, SSMC3, E/OC1 Silver Spring MD USA NODC.Services@noaa.gov http://pathfinder.nodc.noaa.gov originator AVHRR_Pathfinder-NODC-L3C-v5.2 Kenneth S. Casey DOC/NOAA/NESDIS/NODC > National Oceanographic Data Center, NESDIS, NOAA, U.S. Department of Commerce Kenneth.Casey@noaa.gov pointOfContact The AVHRR Pathfinder Version 5.2 Sea Surface Temperature data set (PFV52) is a collection of global, twice-daily 4km sea surface temperature data produced in a partnership by the NOAA National Oceanographic Data Center and the University of Miami's Rosenstiel School of Marine and Atmospheric Science. PFV52 was computed from data from the AVHRR instruments on board NOAA's polar orbiting satellite series using an entirely modernized system based on SeaDAS. This system incorporates several key changes from Versions 5.0 and 5.1 of Pathfinder, including the use of an entirely new land mask, a modified grid, and the inclusion of sea ice, wind speed, and aerosol ancillary data to support the use of the SST data. Importantly, PFV52 data are provided in netCDF-4 (classic model, with internal compression and chunking) and are nearly 100% compliant with the GHRSST Data Specification Version 2.0 for L3C products. These data deviate from that standard only in that sses_bias, sses_standard_deviation, and sst_dtime variables are empty. PFV52 data were collected through the operational periods of the NOAA-7 through NOAA-18 Polar Operational Environmental Satellites (POES), and are available for 1981 through 2012. Data for all years are available as separate NODC accessions. Please acknowledge the use of these data with the following statement: These data were provided by GHRSST and the US National Oceanographic Data Center. CoRIS_MetadataNCEI Geoportal Filter SEA SURFACE TEMPERATURE theme NODC DATA TYPES THESAURUS AVHRR > Advanced Very High Resolution Radiometer AVHRR-GAC instrument NODC INSTRUMENT TYPES THESAURUS satellite data theme NODC OBSERVATION TYPES THESAURUS 326S - SATELLITE NOAA-7 SATELLITE NOAA-9 SATELLITE 3101 - NOAA-11 SATELLITE 3277 - NOAA-14 SATELLITE NOAA-16 SATELLITE NOAA-17 SATELLITE NOAA-18 SATELLITE NOAA-19 SATELLITE platform NODC PLATFORM NAMES THESAURUS PATHFINDER project NODC PROJECT NAMES THESAURUS UNIVERSITY OF MIAMI; ROSENSTIEL SCHOOL OF MARINE AND ATMOSPHERIC SCIENCE US DOC; NOAA; NESDIS; NATIONAL OCEANOGRAPHIC DATA CENTER place NODC COLLECTING INSTITUTION NAMES THESAURUS US DOC; NOAA; NESDIS; NATIONAL OCEANOGRAPHIC DATA CENTER place NODC SUBMITTING INSTITUTION NAMES THESAURUS World-Wide Distribution place NODC SEA AREA NAMES THESAURUS Geographic Region > Global Ocean place NASA/GCMD Location Keywords NASA Global Change Master Directory (GCMD) User Support Office NASA Global Change Master Directory, Goddard Space Flight Center Greenbelt MD 20771 USA gcmduso@gcmd.gsfc.nasa.gov http://gcmd.nasa.gov/index.html http web browser NASA Global Change Master Directory Home Page information http://gcmd.nasa.gov/MailComments/MailComments.jsf?rcpt=gcmduso custodian Oceans > Ocean Temperature > Sea Surface Temperature theme NASA/GCMD Science Keywords NASA Global Change Master Directory (GCMD) User Support Office NASA Global Change Master Directory, Goddard Space Flight Center Greenbelt MD 20771 USA gcmduso@gcmd.gsfc.nasa.gov http://gcmd.nasa.gov/index.html http web browser NASA Global Change Master Directory Home Page information http://gcmd.nasa.gov/MailComments/MailComments.jsf?rcpt=gcmduso custodian climatologyMeteorologyAtmosphere oceans theme ISO 19115 Topic Category 2009-01-01 sea_surface_skin_temperature wind_speed sea_ice_area_fraction time latitude longitude theme NetCDF Climate and Forecast (CF) Metadata Convention EARTH SCIENCE > Oceans > Ocean Temperature > Sea Surface Temperature > AVHRR EARTH SCIENCE > Oceans > Ocean Temperature > Sea Surface Temperature EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Remote Sensing > Satellite (digital scans) > AVHRR theme CoRIS Theme Thesaurus Map Images > Sea Surface Temperature theme CoRIS Discovery Thesaurus OCEAN BASIN > Pacific Ocean OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Hawaiian Islands > Hawaii > Hawaii (21N160W0000) COUNTRY/TERRITORY > United States of America > Hawaii > Hawaii > Hawaii (21N160W0000) OCEAN BASIN > Atlantic Ocean OCEAN BASIN > Indian Ocean OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Guam (13N144E0000) COUNTRY/TERRITORY > United States of America > Guam > Guam (13N144E0000) COUNTRY/TERRITORY > United States of America > Puerto Rico > Puerto Rico (18N066W0000) OCEAN BASIN > Atlantic Ocean > Caribbean Sea /North Atlantic Ocean > Puerto Rico > Puerto Rico (18N066W0000) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Northwestern Hawaiian Islands (28N178W0000) COUNTRY/TERRITORY > United States of America > Hawaii > Honolulu > Northwestern Hawaiian Islands (28N178W0000) COUNTRY/TERRITORY > United States of America > Navassa Island > Navassa Island > Navassa Island (18N075W0001) OCEAN BASIN > Atlantic Ocean > Caribbean Sea > Navassa Island > Navassa Island > Navassa Island (18N075W0001) COUNTRY/TERRITORY > United States of America > U. S. Virgin Islands > U. S. Virgin Islands > U. S. Virgin Islands (17N064W0000) OCEAN BASIN > Atlantic Ocean > Caribbean Sea > Virgin Islands > Lesser Antilles > U. S. Virgin Islands (17N064W0000) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Carolines > Palau ( Belau ) (07N134E0000) COUNTRY/TERRITORY > Palau > Palau > Palau ( Belau ) (07N134E0000) COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > American Samoa (14S170W0000) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Carolines > Micronesia (07N150E0000) COUNTRY/TERRITORY > Micronesia > Micronesia (07N150E0000) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Marshall Islands > Marshall Islands (09N168E0000) COUNTRY/TERRITORY > Marshall Islands > Marshall Islands > Marshall Islands (09N168E0000) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Mariana Archipelago > Northern Mariana Islands ( CNMI ) (18N146E0000) COUNTRY/TERRITORY > Northern Mariana Islands > Northern Mariana Islands > Northern Mariana Islands ( CNMI ) (18N146E0000) COUNTRY/TERRITORY > United States of America > Florida OCEAN BASIN > Atlantic Ocean > North Atlantic Ocean > Florida OCEAN BASIN > Atlantic Ocean > Gulf of Mexico > Florida COUNTRY/TERRITORY > United States of America > Texas > West Flower Garden Banks (27N093W0002) COUNTRY/TERRITORY > United States of America > Texas > East Flower Garden Banks (27N093W0001) OCEAN BASIN > Atlantic Ocean > Gulf of Mexico > Flower Garden Banks > East Flower Garden Banks (27N093W0001) OCEAN BASIN > Atlantic Ocean > Gulf of Mexico > Flower Garden Banks > West Flower Garden Banks (27N093W0002) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Wake Atoll (19N167E0001) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Johnston Atoll (16N169W0001) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Jarvis Island (00S160W0001) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Kingman Reef (06N162W0001) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Palmyra Atoll (05N162W0001) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Howland Island (00S176W0001) COUNTRY/TERRITORY > United States of America > USA Minor Outlying Islands > Baker Island (00N176W0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Wake Atoll > Wake Atoll (19N167E0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Johnston Atoll > Johnston Atoll (16N169W0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Line Islands > Jarvis Island (00S160W0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Line Islands > Kingman Reef (06N162W0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Line Islands > Palmyra Atoll (05N162W0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Howland Island > Howland Island (00S176W0001) OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Baker Island > Baker Island (00N176W0001) OCEAN BASIN > Pacific Ocean > American Samoa > American Samoa (14S170W0000) place CoRIS Place Thesaurus These data are available for use without restriction. Group for High Resolution SST largerWorkCitation project NOAA Climate Data Record Program largerWorkCitation program Unidata Common Data Model grid collection collection grid eng climatologyMeteorologyAtmosphere oceans -180 180 -90 90 Global Ocean 19811031 20121231 The purpose of this data set is to provide sea surface temperature data and related parameters with good temporal consistency, high accuracy and spatial resolution, and for archive and distribution through the NOAA National Oceanographic Data Center (NODC). This SST data collection is intended primarily for climate related applications and studies and is produced with partial support from the NOAA Climate Data Record Program. The Pathfinder Version 5.2 data set follows the international format, content and metadata standard defined by the Group for High Resolution Sea Surface Temperature (GHRSST) in the GHRSST Data Specification Version 2.0 (GDS2.0). These data deviate from that standard only in that sses_bias, sses_standard_deviation, and sst_dtime variables are empty. The GDS2.0 Technical Specifications document can be downloaded from the GHRSST Project Office at https://www.ghrsst.org/documents/q/category/gds-documents/operational/. sea_surface_temperature int16 NOAA Climate Data Record of sea surface skin temperature 0.01 273.15 sst_dtime int32 time difference from reference time 1.0 0 sses_bias int8 SSES bias estimate 0.02 0 sses_standard_deviation int8 SSES standard deviation 0.02 2.54 dt_analysis int8 Deviation from last SST analysis 0.1 0 aerosol_dynamic_indicator int8 aerosol optical thickness 1.0 0 adi_dtime_from_sst int32 time difference of aerosol dynamic indicator from SST 1.0 0 wind_speed int8 10m wind speed 1.0 0 sea_ice_fraction int8 sea ice fraction 0.01 0 quality_level int8 SST measurement quality 5 1 pathfinder_quality_level int8 Pathfinder SST quality flag 7 0 l2p_flags int16 L2P flags time int32 reference time lat single latitude 90 -90 lon single longitude 180 -180 DOC/NOAA/NODC > National Oceanographic Data Center, NOAA, U.S. Department of Commerce (301) 713-3277 (301) 713-3302 SSMC3, 1315 East West Highway Silver Spring MD 20910-3282 USA NODC.Services@noaa.gov 9:00 - 5:00 EST Phone/E-mail/letter. NODC provides data free of charge. distributor For digital delivery, free for all users. For delivery on physical media, users are responsible for the cost of the physical media and production and delivery of the product. 2012-12-08T00:00:00 Delivery of physical media occurs within 1 to 2 weeks, but may take longer for large orders. netCDF netCDF-4 Files are compressed internally using netCDF4. http://accession.nodc.noaa.gov/0071185 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1981. download http://accession.nodc.noaa.gov/0073577 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1982. download http://accession.nodc.noaa.gov/0073578 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1983. download http://accession.nodc.noaa.gov/0073579 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1984. download http://accession.nodc.noaa.gov/0073580 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1985. download http://accession.nodc.noaa.gov/0073581 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1986. download http://accession.nodc.noaa.gov/0073582 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1987. download http://accession.nodc.noaa.gov/0073583 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1988. download http://accession.nodc.noaa.gov/0073584 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1989. download http://accession.nodc.noaa.gov/0073585 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1990. download http://accession.nodc.noaa.gov/0073586 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1991. download http://accession.nodc.noaa.gov/0073587 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1992. download http://accession.nodc.noaa.gov/0073588 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1993. download http://accession.nodc.noaa.gov/0073589 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1994. download http://accession.nodc.noaa.gov/0073590 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1995. download http://accession.nodc.noaa.gov/0073591 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1996. download http://accession.nodc.noaa.gov/0073592 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1997. download http://accession.nodc.noaa.gov/0073593 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1998. download http://accession.nodc.noaa.gov/0073594 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 1999. download http://accession.nodc.noaa.gov/0073595 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2000. download http://accession.nodc.noaa.gov/0073596 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2001. download http://accession.nodc.noaa.gov/0073597 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2002. download http://accession.nodc.noaa.gov/0073598 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2003. download http://accession.nodc.noaa.gov/0073599 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2004. download http://accession.nodc.noaa.gov/0073600 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2005. download http://accession.nodc.noaa.gov/0073601 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2006. download http://accession.nodc.noaa.gov/0073602 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2007. download http://accession.nodc.noaa.gov/0073603 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2008. download http://accession.nodc.noaa.gov/0073604 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2009. download http://accession.nodc.noaa.gov/0073605 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2010. download http://accession.nodc.noaa.gov/0099811 http web browser NODC Ocean Archive System NODC Archival Information Package containing data for 2011. download http://data.nodc.noaa.gov/pathfinder/Version5.2/ http web browser NODC HTTP server Navigate to URL: http://data.nodc.noaa.gov/pathfinder/Version5.2/ and begin browsing through the file hierarchy. Clicking on any of the files will prompt you to download that file or will launch any application associated with netCDF files. download ftp://ftp.nodc.noaa.gov/pub/data.nodc/pathfinder/Version5.2/ ftp Any FTP client NODC FTP server Navigate to URL: ftp://ftp.nodc.noaa.gov/pub/data.nodc/pathfinder/Version5.2/ to download. download http://data.nodc.noaa.gov/thredds/catalog/pathfinder/Version5.2/catalog.html THREDDS Various NODC THREDDS server Thematic Realtime Environmental Distributed Data Services. Provides various web services for data access, including OPeNDAP, HTTP, Web Coverage Service, Web Mapping Service, as well as NCML and ISO views to the data. download cdRom dvd IBM LTO Tape FGDC Attribute Accuracy Report Quality indicators are provided for each data file within the quality_level, pathfinder_quality_level, and dt_analysis variables. FGDC Logical Consistency Report Files are run against the program (algorithm) MD5 to verify data integrity which generates a code, called an MD5 checksum. After files are transferred from one place to another, the program can be run on the file again and a new code generated. The old MD5 checksum code should be identical to the new MD5 checksum code. If not, the file was somehow corrupted during transfer (see original MD5 documentation at http://www.isi.edu/in-notes/rfc1321.txt) FGDC Completeness Report The SST data are nearly complete in the sense that a value is available for nearly every pixel, with the exception of some areas and times where some of the input low-level AVHRR data were missing from the archive. However, after application of the quality flag parameters, the SST fields have extensive gaps due to clouds and other factors which limit the quality of the observed SST. Additional masking information is stored in the l2p_flags variable, which contains bits encoded for the presence of land, sea ice, lakes, and rivers. These data were collected through the operational periods of the NOAA-7 through NOAA-19 Polar Operational Environmental Satellite (POES). A table listing which satellites were used in the generation of Pathfinder V5.0 data for specific dates is available online at: http://www.nodc.noaa.gov/satellitedata/pathfinder4km/userguide.html. FGDC Horizontal Positional Accuracy Report The major sources of error in geo-locating AVHRR data are (a) drift in the spacecraft clock (which causes errors in the estimated along-track position), and (b) uncertainty errors in spacecraft and sensor attitude. (a) Clock Correction: To minimize error in the along track position estimated by the orbital model, a satellite clock correction factor is applied to the time code imbedded in each piece. The method used to determine these clock correction factors is presented below. The clock aboard a given satellite drifts continually at a relatively constant rate (e.g., for NOAA-14, ~9msday-1) compared to the reference clock on Earth. Because of this drift, the NOAA/NESDIS Satellite Operation Control Center periodically sends a command to the satellite to reset the on-board clock to a new baseline thereby eliminating the accumulation of a large time offset error between the Earth and satellite clocks.To correct for clock drift between these resets, correction factors were determined from a database of satellite clock time and Earth time offsets collected at the RSMAS High Resolution Picture Transmission (HRPT) receiving station. During HRPT transmission, both the satellite clock (used to create the embedded time code in each piece) and the Earth clock are simultaneously available. The clock correction bias was determined by (1) visual examination of the Earth/satellite clock differences collected in the database to locate the precise magnitude and timing of clock resets performed by the Satellite Operation Control Center and (2) recorded time differences between the identified reset periods were then filtered to remove spurious noise, and regressed against the corresponding satellite time to determine the clock drift correction. These drift corrections were then applied to all data time-stamped during a given reset period. Refer to Sea Surface Temperature Global Area Coverage (GAC) Processing Appendix A: Calibration and Navigation Correction Factors for a list of clock offsets for each NOAA spacecraft (http://www.rsmas.miami.edu/groups/rrsl/pathfinder/Processing/proc_app_a.html).(b) Attitude Corrections - After clock correction, a nominal attitude correction is then applied to minimize the uncertainty in regard to the direction in which the spacecraft is pointing. The nominal attitude correction applied was determined by averaging the absolute attitude of the spacecraft over many geographic locations and times along the orbital track. The method used to determine the absolute attitude of the spacecraft involves matching a digital coastal outline to a given image and recording the amount of pitch, yaw, and roll required to make the outline and land coincide. This method has the advantage that it can be performed over small geographical distances and is similar to other techniques which rely on widely separated geographical control points to anchor the navigation. The resultant navigation information, output by the SECTOR procedure for each piece, provides the mapping parameters needed to convert between the satellite perspective of pixel and scan line, and Earth-based latitude and longitude coordinates. Refer to Sea Surface Temperature Global Area Coverage (GAC) Processing Appendix A: Calibration and Navigation Correction Factors for attitude correction factors for each NOAA spacecraft (http://www.rsmas.miami.edu/groups/rrsl/pathfinder/Processing/proc_app_a.html). FGDC Vertical Positional Accuracy Report dataset Pathfinder Version 5.2 data are produced from Level 1b AVHRR Global Area Coverage (GAC) data using code based on the SeaDAS v6.1 processing environment. The output of this process is a collection of twice-daily, global Level 3 data files in HDF4 format. The process requires several important pieces of information, which are categorized by the following four overall steps in the Pathfinder processing system (steps A-D): A. Ingestion, calibration, and navigation of Global Area Coverage (GAC) data. Sub-steps: a. Calibrate and convert AVHRR digital counts for channels 1 through 5 to radiances - i. Obtain AVHRR channels 1 through 5 radiometer count data; ii. Channels 1 and 2 require pre-launch calibration coefficients for linear counts-to-radiance conversion, followed by a correction for temporal changes using sensor decay rate data and then a correction for inter-satellite differences using inter-satellite standardization data to the NOAA-9 reference, both of which use Libyan desert target area data; iii. Channels 3, 4, and 5 require both the pre-launch calibration data and onboard blackbody (space view and sensor base plate) data for non-linear counts-to-radiance conversion; b. Navigation, Clock, and Attitude Corrections; i. Satellite clock corrections need Earth time offset data based on RSMAS High-Resolution Picture Transmission data; ii. Attitude corrections are made using coastline comparison data; iii. At this point, navigated, calibrated albedos/brightness temperatures are available for all five channels. Note that channels 1-2 are not used in the Pathfinder SST algorithm, and channel 3 is used only in assignment of a quality indicator (see step B.d.i.). B. SST Calculation. Sub-steps: a. Channel 4 and 5 brightness temperatures are converted to SST in degrees C using the Pathfinder algorithm, which requires a set of monthly coefficients; b. These coefficients are derived using the Pathfinder Buoy Matchup Database. This is a set of in situ buoy SST observations and collocated AVHRR data; c. In addition, a first-guess SST field is needed by the algorithm. This first-guess field is the Reynolds Optimum Interpolation ¼-Degree Daily SST Analysis version 2 (DOISSTv2) product, with inland values populated from the AVHRR Pathfinder Version 5.0/5.1 daily climatological SST. (For more information on this reference field see http://accession.nodc.noaa.gov/0071185). Note: Pathfinder Version 5.0 used the Reynolds Weekly Global Optimally Interpolated SST Version 2 (OISSTv2); d. Quality Flag Assignment - i. A Channel 3, 4, and 5 brightness temperature test is performed. These data are already available from step A.a.iii; ii. The viewing angle is evaluated using a satellite zenith angle check; iii. A reference field comparison check is made against the Reynolds DOISSTv2 used in step B.c.; iv. A stray sunlight test is performed which requires information on whether the data in question are to left or right of nadir; v. An edge test is performed which checks the location of the pixel within a scan line and the location of the scan line within the processing piece (a 'piece' is a subset of an entire orbit file); vi. A glint test is performed which requires a glint index calculated according to the Cox and Munk (1954) formulation; vii. The preceding steps are all combined into an overall quality flag assignment for each pixel. C. Spatial Binning. Sub-steps: a. An equal-area grid is defined into which GAC pixels are binned. No external data are needed, only information on the equal-area binning strategy itself; b. A data-day is defined following a spatial data-day definition. See http://www.nodc.noaa.gov/satellitedata/pathfinder4km/Data-day.pdf for a description of the spatial data-day definition, written by Guillermo Podesta, University of Miami RSMAS; c. A land mask is applied to the dataset, identifying pixels that fall on land. This land mask was generated by rasterizing the Global Self-consistent Hierarchical High-resolution Shoreline (GSHHS) Database from the NOAA National Geophysical Data Center. Any 4km Pathfinder pixel whose area is 50% or more covered by land is considered land in this land mask. Inland water bodies were incorporated into this land mask by rasterizing the US World Wildlife Fund's Global Lakes and Wetlands Database. Any 4km Pathfinder pixel whose area is 50% or more covered by lake or river was considered water for in this land mask. D. Temporal Binning. Sub-steps: a. The spatially binned pieces from step C are accumulated into a single ascending (daytime) or descending (nighttime) file for each day. In case of overlapping satellite passes, only the best pixels of equivalent quality are binned. No external information is needed, only information about the accumulation procedure itself; b. Fields are reprojected from equal-area to the 8640x4320 equal-angle grid. Robert Evans University of Miami Rosenstiel School of Marine and Atmospheric Science Research Professor (305)421-4799 4600 Rickenbacker Causeway Miami FL 33149 revans@rsmas.miami.edu 9 - 5 EST principalInvestigator Twice-daily global L3 Pathfinder files in HDF4 are transferred from the University of Miami to the National Oceanographic Data Center, where they are converted into GDS2.0-compliant netCDF4. Details of this process are as follows: 1. Start time, end time, satellite ID, and orbit node (ascending or descending) are read from the input L3 HDF file and used to generate the name of the output netCDF file. (Note: The GDS2.0 standard requires the center time of collation to be the indicative time used in the filename for an L3C file.); 2. The reference time of the HDF file is converted to GDS2.0 "seconds since 1981-01-01 00:00:00" format and written to the netCDF file along with latitude and longitude values for the Pathfinder Version 5.2 grid; 3. Sea surface temperature data from the HDF "SST" file are written to the sea_surface_temperature variable in the netCDF file; 4. GDS2.0-required variables sst_dtime, sses_bias, and sses_standard_deviation are written to the netCDF file and populated with fill values. Note: Pathfinder Version 6.0 will contain actual values for these three variables; 5. Reference SST data from the corresponding HDF "REF" file are combined with the SST data to populate the dt_analysis variable in the netCDF file; 6. Wind speed data are written to the wind_speed variable in the netCDF file. These data are created by the NCEP-DOE Atmospheric Model Intercomparison Project (AMIP-II) reanalysis (R-2) and represent winds at 10 meters above the sea surface. They are interpolated to the Pathfinder Version 5.2 grid prior to processing; 7. Sea ice data are written to the sea_ice_fraction variable in the netCDF file. These data are taken from the EUMETSAT Ocean and Sea Ice Satellite Application Facility (OSISAF) Global Daily Sea Ice Concentration Reprocessing Data Set (http://accession.nodc.noaa.gov/0068294) when these data are available. The data are reprojected and interpolated from their original polar stereographic projection at 10km spatial resolution to the 4km Pathfinder Version 5.2 grid. When the OSISAF data are not available for both hemispheres on a given day, the sea ice concentration data are taken from the sea_ice_fraction variable found in the L4 GHRSST DailyOI SST product from NOAA/NCDC, and are interpolated from the 25km DailyOI grid to the 4km Pathfinder Version 5.2 grid; 8. Aerosol data are written to the aerosol_dynamic_indicator and adi_dtime_from_sst variables in the netCDF file. These data are pulled from three different sources and interpolated to the Pathfinder Version 5.2 grid prior to processing. For 1981-2000, AVHRR Pathfinder Atmospheres (PATMOS-A2) data from the NOAA Office of Satellite Data Processing and Distribution (OSDPD) are used. For 2003-2009, AVHRR Pathfinder Atmospheres - Extended (PATMOS-X) data from NOAA OSDPD are used. For 2001-2002 2012, data are taken from the OMI/Aura Aerosol Optical Depth and Single Scattering Albedo Daily L2 Global 0.25 degree gridded v003 product (OMAEROG), produced by the US NASA Goddard Earth Sciences Data and Information Services Center; 9. Original Pathfinder quality levels are read from the HDF file, mapped to the 6 quality levels required by the GDS2.0, and written to the variable quality_level in the netCDF file. The quality levels are as follows: GDS quality_level 5 = native Pathfinder quality level 7 == best_quality; GDS quality_level 4 = native Pathfinder quality_level 4-6 == acceptable_quality; GDS quality_level 3 = native Pathfinder quality level 2-3 == low_quality; GDS quality_level 2 = native Pathfinder quality level 1 == worst_quality; GDS quality_level 1 = native Pathfinder quality level 0 == bad_data; GDS quality_level 0 = native Pathfinder quality level -1 == missing_data; 10. The original Pathfinder quality level is written to the optional variable pathfinder_quality_level in the netCDF file; 11. River, lake, and land information from the Pathfinder Version 5.2 land mask, as well as sea ice presence information from the sea ice data described previously, are encoded in bits and written to the bit mask variable l2p_flags in the netCDF file; 12. Global attributes are written to the netCDF file according to GDS2.0 requirements; 13. Final AVHRR Pathfinder Version 5.2 data are quality assured through browse graphic generation and inspection. Upon completion of the quality assurance routines, the data are archived by the National Oceanographic Data Center and published online. Kenneth Casey DOC/NOAA/NESDIS/NODC > National Oceanographic Data Center, NESDIS, NOAA, U.S. Department of Commerce Technical Director (301)713-3272 x133 1315 East West Highway, SSMC3 E/OC Silver Spring MD 20910 Kenneth.Casey@noaa.gov 7 - 4 EST pointOfContact 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. 20130630 This record will be translated to FGDC for inclusion in NODC Web Accessible Folders. Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-7 Satellite Launched: June 23, 1981. Instruments: AVHRR, TOVS, DCLS, SEM. Status: Retired. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-9 Satellite Launched: December 12, 1984. Instruments: AVHRR, TOVS, DCLS, SEM, ERBE, SARSAT, SBUV/2. Status: Retired. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-11 Satellite Launched: September 24, 1988. Instruments: AVHRR, TOVS, DCS, SAR, SBUV/2. Status: Retired. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-14 Satellite Launched: December 29, 1994. Instruments: AVHRR, TOVS, ARGOS, SARSAT, SEM, RAIDS. Status: Retired. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-16 Satellite Launched: September 21, 2000. Instruments: AVHRR, HIRS/3, AMSU/A, AMSU/B, SEM-2, SARSAT, DCS-2. Status: PM Secondary. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-17 Satellite Launched: June 24, 2002. Instruments: AVHRR, HIRS/3, AMSU/A, AMSU/B, SEM-2, SBUV/2, SARSAT, DCS-2. Status: AM Backup. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-18 Satellite Launched: May 20, 2005. Instruments: AVHRR, HIRS/3, AMSU/A, AMSU/B, SEM-2, SBUV/2, SARSAT, DCS-2. Status: PM Secondary. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter. NOAA-19 Satellite Launched: February 6, 2009. Instruments: AVHRR/3, HIRS/4, AMSU/A, MHS, SEM-2, SBUV/2, SAR, ADCS. Status: PM Secondary. Orbit: Sun-synchronous. US DOC/NOAA/OSO > Office of Satellite Operations, National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator Advanced Very High Resolution Radiometer - AVHRR publication US DOC/NOAA > National Oceanic and Atmospheric Administration, U.S. Department of Commerce originator AVHRR > Advanced Very High Resolution Radiometer radiometer The AVHRR/3 is a six-channel imaging radiometer which detects energy in the visible and infrared (IR) portions of the electromagnetic spectrum. The instrument measures reflected solar (visible and near-IR) energy and radiated thermal energy from land, sea, clouds, and the intervening atmosphere. The instrument has an instantaneous field-of-view (IFOV) of 1.3 milliradians providing a nominal spatial resolution of 1.1 km (0.69 mi) at nadir. A continuously rotating elliptical scan mirror provides the cross-track scan, scanning the Earth from ± 55.4° from nadir. The mirror scans at six revolutions per second to provide continuous coverage. The AVHRR/3 provides spectral and gain improvements to the solar visible channels that provide low light energy detection. Channel 3A, at 1.6 microns, provides snow, ice, and cloud discrimination. Channel 3A will be time-shared with the 3.7- micron channel, designated 3B, to provide five channels of continuous data. An external sun shield and an internal baffle have been added to reduce sunlight impingement into the instruments optical cavity and detectors. An AVHRR instrument is flown on board each of the NOAA Polar Operational Environmental Satellites (POES). For these satellites, the hysteris scan mirror has been replaced with a Brushless DC motor. This motor is more reliable and operates with significantly reduced jitter.