Index of /cortad

 Name                    Last modified      Size  Description
 Parent Directory                             -   
 README.html             13-Aug-2015 14:31  4.0K  
 README.html~            02-May-2012 14:37  2.6K  
 README.txt              13-Aug-2015 14:31  3.9K  
 README.txt~             02-May-2012 14:28  2.4K  
 Version1/               28-Aug-2008 22:31    -   
 Version2/               16-Mar-2010 18:49    -   
 Version3/               07-Dec-2010 18:29    -   
 Version4/               21-Jun-2012 22:33    -   
 Version5/               27-Apr-2015 15:00    -   

CoRTAD - Coral Reef Temperature Anomaly Database Version 5:

The Coral Reef Temperature Anomaly Database (CoRTAD) is a collection of sea surface temperature (SST) and related thermal stress metrics, developed specifically for coral reef ecosystem applications but relevant to other ecosystems as well. The CoRTAD Version 5 contains global, approximately 4 km resolution SST data on a weekly time scale from 1982 through 2012. The purpose of the CoRTAD is to provide sea surface temperature data and related thermal stress parameters with good temporal consistency, high accuracy, and fine spatial resolution. The CoRTAD is intended primarily for climate and ecosystem related applications and studies and was designed specifically to address questions concerning the relationship between coral disease and bleaching and temperature stress.

Version Changes:
Version 5, 1982-01-02 - 2012-12-28, Global 4320x8640x1617 netCDF-4.1.2
Version 4, 1981-10-31 - 2010-12-31, Global 4320x8640, Tile 540x540, NetCDF-4 Classic
Version 3, 1982-01-01 - 2009-12-31, Global 4096x8192, Tile 512x512, HDF5
Version 2, 1982-01-01 - 2008-12-31, Global 4096x8192, Tile 512x512, HDF5
Version 1, 1985-01-01 - 2005-12-31, Global 4096x8192, Tile 512x512, HDF4
NODC Accession Numbers: v5 126774; v4 0087989; v3 0068999; v2 0054501; v1 0044419

Like its previous version (CoRTAD 4), CoRTAD 5 is derived from Pathfinder 5.2 Sea Surface Temperatue as well, while CoRTAD 3 utilized Pathfinder 5.1 and 5.0. CoRTAD 5 has 22 extra months of data and was developed using 1982-2012 data from the Pathfinder Version 5.2 collection produced by the National Oceanic and Atmospheric Administration's (NOAA) National Centers for Environmental Information (NCEI) (http://pathfinder.nodc.noaa.gov). These SST data are derived from the Advanced Very High Resolution Radiometer (AVHRR) sensor and are processed to a resolution of approximately 4.6 km at the equator. These data have the highest resolution covering the longest time period of any satellite-based ocean temperature dataset. Daytime and nighttime data were averaged weekly using data with a quality flag of 4 or better. Previous versions of CoRTAD (versions 1-3) also incorporated pixels up to 5 degrees warmer than a course resolution reference SST based on the Reynolds Optimum Interpolation Sea Surface Temperature (Weekly, 1-degree OISST version 2.0). Since Pathfinder Version 5.2 already uses a finer resolution reference field (25 km Daily OISST) this additional step was not incorporated here in CoRTAD Version 5, or in the previous CoRTAD Version 4. These processes resulted in a weekly SST dataset that is roughly 80% gap free.

Please note in both CoRTAD Versions 4 and 5, a gap exists in the Pathfinder 5.2 dataset from 1994 day 275 to 1995 day 17 since Level 1B GAC data from NOAA-9 is not available from the NOAA archives. For these 3.5 months, SST has been interpolated from Pathfinder 5.0 and 0.17K is subtracted to transform the data to the skin temperature basis of Pathfinder 5.2. In CoRTAD Version 5, the data are not stored in separate geographic tiles like in Version 4 and earlier. Instead, each data file contains the entire global coverage for a related grouping of CoRTAD parameters.

In addition to SST, the CoRTAD contains SST anomaly (SSTA, weekly SST minus weekly climatological SST), thermal stress anomaly (TSA, weekly SST minus the maximum weekly climatological SST), SSTA Degree Heating Week (SSTA_DHW, sum of previous 12 weeks when SSTA >= 1 degree C), SSTA Frequency (number of times over the previous 52 weeks that SSTA >= 1 degree C), TSA DHW (TSA_DHW, also known as Degree Heating Week, sum of previous 12 weeks when TSA >= 1 degree C), and TSA Frequency (number of times over previous 52 weeks that TSA >=1 degree C). The CoRTAD was created at the NOAA NCEI with support from the NOAA Coral Reef Conservation Program.