***************************************************************** Journal for accession number: 0054413 Created on: 2009-06-10 09:23:55 UTC By: NODC archive manager Source: Group for High Resolution Sea Surface Temperature (GHRSST) Data These data were submitted for archive to the NODC as part of GHRSST (the Group for High Resolution Sea Surface Temperature, formerly known as the Global Ocean Data Assimilation Experiment (GODAE) High Resolution Sea Surface Temperature Pilot Project, GHRSST-PP). GHRSST maintains an internationally distributed operational system that delivers global coverage high-resolution (better than 10 km and ~6 hourly) near-real time SST data products and delayed mode climate data record SST products. GHRSST is based on a global task-sharing system in which the data processing operations are shared by Regional Data Assembly Centres (RDACs), Global Data Assembly Centres (GDACs), and a Long Term Stewardship and Reanalysis Facility (LTSRF, maintained by NODC). The RDACs ingest, quality control and merge existing satellite and in situ SST data sources that are then merged together to generate regional coverage SST data products having the same netCDF format specification (called L2P products), in real-time. RDACs also produce gridded Level 3 (L3) and gap-free Level 4 (L4) analysis products, all of which are then assembled together at the GDAC. For a complete description of GHRSST including data processing and metadata specifications, please refer to: The Recommended GHRSST-PP Data Processing Specification GDS (Version 1 revision 1.5), GHRSST-PP Report Number 17, compiled by Craig Donlon and the GHRSST Science Team, Published by the International GHRSST Project Office, Met Office, Fitzroy Road, Exeter, EX3 1PB, United Kingdom, downloadable from the References section of the GHRSST site at: http://www.ghrsst-pp.org/. (Note that in June 2009 the GHRSST Science Team will be releasing a new Version 2 of the GHRSST Data Specification). The role of the NODC within this international project is to serve as the long term stewardship center where reprocessing efforts to create climate-quality SST products are coordinated internationally, and where all GHRSST data are made available in perpetuity. GHRSST data are received daily by the NODC 30 days after observation (prior to 30 days they are available through the GDAC interface) through an automated procedure made possible largely by the formalized procedures developed within GHRSST, especially those pertaining to data management, metadata, and file naming conventions. The basic strategy is to bring in data files and corresponding FGDC metadata in XML format on a daily basis, then use a combination of static information, information from the filenames, information from within the XML metadata records, and information generated by the NODC archive system to automatically create an ATDB entry and accession for each logical grouping of data (there are currently nearly 30 product groupings each day) and then move the relevant data files (there may be several per accession) and FGDC record into the NODC archive file systems. On a routine basis, an http/ftp/OPeNDAP hierarchy is then constructed of symbolic links pointing to the data and metadata residing in the formal NODC archive file system. The GHRSST data streams consist of three types of data and metadata. The three types of data managed using the procedures documented here make up the core of the GHRSST system. These data types, in netCDF format, are: Level 2 Preprocessed (L2P) ---------------------------------- Individual satellite sensor observations processed into geophysical units (SST in degrees C) and formatted according to the GHRSST-PP Data Processing Specifications (GDS v1.5, GHRSST/17) or more recent versions of the GDS. L2P data contain SST derived from Level 1 source data (which are outside of the scope of GHRSST) at the same resolution and location as the Level 1 data, typically in a satellite projection with geographic information. These data form the fundamental basis for higher-level derived GHRSST products and include, importantly, extensive ancillary data and uncertainty estimates. Level 3 (L3) --------------- These data are Level 2 variables mapped on a defined grid with reduced GHRSST requirements for ancillary data. Uncertainty estimates are still mandatory. The reduced requirements for ancillary data help distinguish L3 GHRSST from L2 GHRSST. L3 GHRSST products include un-collated data that represent a simple remapping of L2 GHRSST data granules to a space grid without combining any observations from overlapping orbits, collated data that combine observations from a single instrument into a space-time grid, and multi-sensor super-collated data that combine observations from a multiple instruments into a space-time grid. Note that L3 GHRSST products do not use analysis or interpolation procedures to fill all gaps where no observations are available. Level 4 (L4) --------------- These are data sets created from the analysis of lower level data that results in gridded, gap-free products. SST data generated from multiple sources of satellite data using optimal interpolation are an example of L4 GHRSST products. L2P, L3, and L4 data are stored in netCDF format following the procedures detailed in the GDS. The netCDF files are compressed using gzip or bzip2 compression and can be decompressed with freely-available software (e.g., http://www.bzip.org/). Summary of GHRSST data management structure: 1. Data processing is managed by a distributed system with international partners at Regional Data Assembly Centers (RDACs) around the world. 2. The RDACs generate data and GCMD-DIF style metadata for L2P, L3, and L4 products. 3. All RDAC data streams are sent first to the Global Data Assembly Center (GDAC) at the NASA JPL/Caltech Physical Oceanography Distributed Active Archive Center (PO.DAAC). The PO.DAAC (http:/ghrsst.jpl.nasa.gov/), provides critical data management functions and user access to these real-time data. The PO.DAAC holds the data in a 30 day rolling store, and constructs an XML-formatted FGDC-compliant metadata record for each logical grouping of data (an NODC "Accession" or Archival Information Package) based on the GCMD-DIF style metadata mandated as part of the GHRSST system. 4. The PO.DAAC GDAC system makes these data available to NODC 30 days after observation. These data may be retrieved from the NODC via several mechanisms at: 1. NODC Ocean Archive System: http://www.nodc.noaa.gov/search/prod/ 2. HTTP Server: http://data.nodc.noaa.gov/ghrsst 3. FTP Server: ftp://data.nodc.noaa.gov/pub/data.nodc/ghrsst 4. OPeNDAP Server: http://data.nodc.noaa.gov/cgi-bin/nph-dods/ghrsst See the NODC GHRSST Web site: http://ghrsst.nodc.noaa.gov for more information. Files: L4/GLOB/NAVO/K10_SST/2009/120/FGDC-20090430-NAVO-L4HR1m-GLOB-v01-K10_SST.xml - FGDC metadata record describing the following data files in this accession: 20090430-NAVO-L4HR1m-GLOB-v01-fv01_0-K10_SST.nc.bz2 FR-20090430-NAVO-L4HR1m-GLOB-v01-fv01_0-K10_SST.xml NODC updates to metadata: 1.1 Citation 8.4 Title: appended " for 2009-04-30 (NODC Accession 0054413)" 1.5.1 Bounding Coordinates: calculated by finding the maximum and minimum range domains for the Latitude and Longitude attributes in this accession's 1 constituent entities identified in section 5: Entity and Attribute Information 1.5.1.1 West Bounding Coordinate: changed from -180.000 to -180.000 1.5.1.2 East Bounding Coordinate: changed from 180.000 to 179.900 1.5.1.3 North Bounding Coordinate: changed from 90.000 to 90.000 1.5.1.4 South Bounding Coordinate: changed from -90.000 to -90.000 6.2 Resource Description: set to "NODC ACCESSION # 0054413" 6.4.2.1.7 Transfer Size: changed from 15000000 to 2.720 (actual) 6.4.2.1.7 Transfer Size: changed from 15000000 to 2.720 (actual) 6.4.2.1.7 Transfer Size: changed from 15000000 to 2.720 (actual) 7.1 Metadata Date: changed from 20041023 to 20090610 7.2 Metadata Review Date: changed from 20041023 to 20090610 7.3 Metadata Future Review Date: changed from 20050331 to 20100610 ***************************************************************** NODC accession number: 0054413 Version: 2.2 Updated on: 2011-11-01 20:45:32 UTC By: Automated Ingest Agent Updates were received for this data set. Updates may provide additional files or replace obsolete files. However, all of the files received prior to this update are available in the preceding version of this accession. Updates received on: 2011-10-21 The RDAC has provided updates to the files in this data set. NODC received the updates from the GDAC on the date shown above. For more information on this update, please contact the Technical Contact for the RDAC, listed in the FGDC metadata record in this directory. Total number of files: 3 Number of new files: 0 Number of changed files: 1 Number of files removed: 0 Changed files: FGDC-20090430-NAVO-L4HR1m-GLOB-v01-K10_SST.xml NODC updates to metadata: 1.1 Citation 8.4 Title: appended " for 2009-04-30 (NODC Accession 0054413)" 1.5.1 Bounding Coordinates: calculated by finding the maximum and minimum range domains for the Latitude and Longitude attributes in this accession's 1 constituent entities identified in section 5: Entity and Attribute Information 1.5.1.1 West Bounding Coordinate: changed from -180.000 to -180.000 1.5.1.2 East Bounding Coordinate: changed from 180.000 to 179.900 1.5.1.3 North Bounding Coordinate: changed from 90.000 to 90.000 1.5.1.4 South Bounding Coordinate: changed from -90.000 to -90.000 6.4.2.1.7 Transfer Size: changed from 15000000 to 2.745 (actual) 6.4.2.1.7 Transfer Size: changed from 15000000 to 2.745 (actual) 6.4.2.1.7 Transfer Size: changed from 15000000 to 2.745 (actual) 7.1 Metadata Date: changed from 20041023 to 20111101 7.2 Metadata Review Date: changed from 20041023 to 20111101 7.3 Metadata Future Review Date: changed from 20050331 to 20121101