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Dataset Overview | National Centers for Environmental Information (NCEI)

The Coral Reef Temperature Anomaly Database (CoRTAD) Version 6 - Global, 4 km Sea Surface Temperature and Related Thermal Stress Metrics for 1982 to 2019

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Version 6 of the Coral Reef Temperature Anomaly Database (CoRTAD) is a global, 4 km, sea surface temperature (SST) and related thermal stress metrics dataset for 1982-01-02 to 2019-12-27. The CoRTAD contains weekly-averaged SSTs, 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 is greater than or equal to 1 degree C), SSTA Frequency (number of times over previous 52 weeks that SSTA is greater than or equal to 1 degree C), TSA DHW (TSA_DHW, also known as a Degree Heating Week, sum of previous 12 weeks when TSA is greater than or equal to 1 degree C), and TSA Frequency (number of times over previous 52 weeks that TSA is greater than or equal to 1 degree C). In addition, the CoRTAD includes ancillary sea ice concentration and marine wind speed data. These data are the sixth in the series of CoRTAD datasets originally created in association with Elizabeth Selig (Director, Marine Science, Conservation International) and John Bruno (University of North Carolina; UNC - Chapel Hill). This dataset is based on the Pathfinder V5.3 dataset, and is created with support from the NOAA Coral Reef Conservation Program.
  • Cite as: Saha, Korak; Zhao, Xuepeng; Zhang, Huai-min; Casey, Kenneth S.; Zhang, Dexin; Zhang, Yongsheng; Baker-Yeboah, Sheekela; Relph, John M.; Krishnan, Ajay; Ryan, Thomas (2018). The Coral Reef Temperature Anomaly Database (CoRTAD) Version 6 - Global, 4 km Sea Surface Temperature and Related Thermal Stress Metrics for 1982 to 2019. [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/ffw7-cs39. Accessed [date].
gov.noaa.nodc:NCEI-CoRTADv6
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Distribution Formats
  • netCDF (Version: 4.1.2)
    • File Specification: NCEI_NetCDF_Grid_Template_v2.0, CF-1.6, ACDD-1.3
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Distributor NOAA National Centers for Environmental Information
NCEI.Info@noaa.gov
Dataset Point of Contact NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Time Period 1982-01-02 to 2020-12-25
Spatial Bounding Box Coordinates
N: 90
S: -90
E: 180
W: -180
Spatial Coverage Map
General Documentation
Associated Resources
Publication Dates
  • publication: 2018-08-17
  • revision: 2021-04-27
Data Presentation Form Digital table - digital representation of facts or figures systematically displayed, especially in columns
Dataset Progress Status Complete - production of the data has been completed
Historical archive - data has been stored in an offline storage facility
Data Update Frequency As needed
Supplemental Information
[Text below adapted from: Selig, E.R., K.S. Casey, and J.F. Bruno (2010). New insights into global patterns of ocean temperature anomalies: implications for coral reef health and management, Global Ecology and Biogeography, https://doi.org/10.1111/j.1466-8238.2009.00522.x. Hereafter referred to as "SCB2010".] The CoRTAD version 6 was developed using 1982-2020 data from the Pathfinder Version 5.3 collection (Saha et al., 2018) produced by the National Oceanic and Atmospheric Administration's (NOAA) National Centers for Environmental Information (NCEI) (https://www.nodc.noaa.gov/satellitedata/pathfinder4km53/). These sea surface temperature 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. This level is a commonly accepted cutoff for "good" data (Kilpatrick et al., 2001, Casey and Cornillon, 1999). 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 5.3 already uses a finer resolution reference field (25 km Daily OISST) this additional step was not incorporated here in CoRTAD (for later Versions 4-6) (Casey et al., 2012). These processes resulted in a weekly SST dataset that is roughly 80% gap free. To create a gap-free dataset for analysis, 3 x 3 pixel median spatial fill was used. A temporal fill was then performed using the nonlinear least squares data fitting (Levenberg-Marquardt algorithm) in SLATEC Common Mathematical Library (in public domain) to fill the remaining gaps. This conservative approach was chosen because it provided interpolated SSTs that are bounded by the nearest available values in time. It also used data from only a very limited spatial domain, which is an important consideration given the variability of coral reef environments. Using these gap-filled data, we then created site-specific climatologies for each reef grid cell to describe long-term temperature patterns over the 35-year dataset. The climatology was generated using a harmonic analysis procedure that fits annual and semi-annual signals to the time series of weekly SSTs at each grid cell: climSST(t) = A*cos(2pi*t + B) + C*cos(4pi*t + D) + E (1), where t is time, A and B are coefficients representing the annual amplitude and phase, C and D are the semi-annual amplitude and phase, and E is the long-term temperature mean. Others have used similar approaches for generating climatologies because they are more robust than simple averaging techniques, which can be more susceptible to data gaps from periods of cloudiness (Podesta et al., 1991, Mesias et al., 2007). Please note in CoRTAD Versions 4 to 6, a gap exists in the Pathfinder 5.3 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 Version 5.3. Similar to Version 5, CoRTAD version 6 data are not stored in separate geographic tiles as was the case for version 4 and its predecessors. Instead, each data file contains the entire global coverage for a related grouping of CoRTAD parameters. Following are the version changes at glance:
Version 6, 1982-01-02 - 2020-12-25, Global 4320x8640x2034 netCDF-4.2.1.1
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
NCEI Accession Numbers: v3 0068999; v2 0054501; v1 0044419
Purpose To quantify the spatial and temporal characteristics of ocean temperature anomalies related to both coral bleaching and disease.
Use Limitations
  • accessLevel: Public
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Dataset Citation
  • Cite as: Saha, Korak; Zhao, Xuepeng; Zhang, Huai-min; Casey, Kenneth S.; Zhang, Dexin; Zhang, Yongsheng; Baker-Yeboah, Sheekela; Relph, John M.; Krishnan, Ajay; Ryan, Thomas (2018). The Coral Reef Temperature Anomaly Database (CoRTAD) Version 6 - Global, 4 km Sea Surface Temperature and Related Thermal Stress Metrics for 1982 to 2019. [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/ffw7-cs39. Accessed [date].
Cited Authors
Contributors
Resource Providers
Points of Contact
Publishers
Theme keywords NODC DATA TYPES THESAURUS NODC OBSERVATION TYPES THESAURUS WMO_CategoryCode
  • climatology
  • oceanography
  • satelliteObservation
Global Change Master Directory (GCMD) Science Keywords NetCDF Climate and Forecast (CF) Metadata Convention Standard Name Table
  • land_binary_mask
  • latitude
  • longitude
  • maximum_of_gap_filled_sea_surface_skin_temperature
  • mean_of_gap_filled_sea_surface_skin_temperature
  • minimum_of_gap_filled_sea_surface_skin_temperature
  • sea_ice_area_fraction
  • sea_surface_skin_temperature
  • time
  • wind_speed
Data Center keywords Global Change Master Directory (GCMD) Data Center Keywords NODC COLLECTING INSTITUTION NAMES THESAURUS NODC SUBMITTING INSTITUTION NAMES THESAURUS
Platform keywords NODC PLATFORM NAMES THESAURUS Global Change Master Directory (GCMD) Platform Keywords ICES/SeaDataNet Ship Codes
Instrument keywords NODC INSTRUMENT TYPES THESAURUS Global Change Master Directory (GCMD) Instrument Keywords
Place keywords NODC SEA AREA NAMES THESAURUS Global Change Master Directory (GCMD) Location Keywords
Project keywords NODC PROJECT NAMES THESAURUS
Keywords NCEI ACCESSION NUMBER
Use Constraints
  • Cite as: Saha, Korak; Zhao, Xuepeng; Zhang, Huai-min; Casey, Kenneth S.; Zhang, Dexin; Zhang, Yongsheng; Baker-Yeboah, Sheekela; Relph, John M.; Krishnan, Ajay; Ryan, Thomas (2018). The Coral Reef Temperature Anomaly Database (CoRTAD) Version 6 - Global, 4 km Sea Surface Temperature and Related Thermal Stress Metrics for 1982 to 2019. [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/ffw7-cs39. Accessed [date].
  • Please acknowledge the use of these data with the following statement: These data were provided by the US National Centers for Environmental Information. This project was supported in part by a grant from the NOAA Climate Data Record (CDR) Program for satellites and the NOAA Coral Reef Conservation Program.
Access Constraints
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Fees
  • In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: series
Processing Steps
  • 2018-08-17T07:41:56Z - NCEI Accession 0175420 v1.1 was published.
  • 2018-08-17T16:06:25Z - NCEI Accession 0175481 v1.1 was published.
  • 2018-08-17T19:43:11Z - NCEI Accession 0175482 v1.1 was published.
  • 2018-08-18T16:56:40Z - NCEI Accession 0175483 v1.1 was published.
  • 2018-08-20T12:54:36Z - NCEI Accession 0175546 v1.1 was published.
  • 2018-08-20T16:56:23Z - NCEI Accession 0175547 v1.1 was published.
  • 2018-08-20T18:58:59Z - NCEI Accession 0175549 v1.1 was published.
  • 2018-08-20T20:03:24Z - NCEI Accession 0175550 v1.1 was published.
  • 2018-08-28T03:39:44Z - NCEI Accession 0175547 was revised and v2.2 was published.
  • 2019-08-03T05:27:06Z - NCEI Accession 0192832 v1.1 was published.
  • 2019-08-05T23:51:42Z - NCEI Accession 0194306 v1.1 was published.
  • 2019-08-07T22:31:57Z - NCEI Accession 0195034 v1.1 was published.
  • 2019-08-10T09:04:48Z - NCEI Accession 0195417 v1.1 was published.
  • 2019-08-11T21:09:59Z - NCEI Accession 0196074 v1.1 was published.
  • 2019-08-14T09:03:17Z - NCEI Accession 0196822 v1.1 was published.
  • 2019-08-15T23:30:42Z - NCEI Accession 0197564 v1.1 was published.
  • 2019-08-17T18:03:49Z - NCEI Accession 0198252 v1.1 was published.
  • 2020-03-04T08:58:13Z - NCEI Accession 0209168 v1.1 was published.
  • 2020-03-05T17:55:57Z - NCEI Accession 0209185 v1.1 was published.
  • 2020-03-07T21:16:26Z - NCEI Accession 0209198 v1.1 was published.
  • 2020-03-10T09:48:53Z - NCEI Accession 0209244 v1.1 was published.
  • 2020-03-11T18:04:41Z - NCEI Accession 0209270 v1.1 was published.
  • 2020-03-16T05:36:58Z - NCEI Accession 0209310 v1.1 was published.
  • 2020-03-17T22:01:04Z - NCEI Accession 0209317 v1.1 was published.
  • 2020-03-19T20:17:08Z - NCEI Accession 0209327 v1.1 was published.
  • 2021-04-13T16:54:54Z - NCEI Accession 0229121 v1.1 was published.
  • 2021-04-15T09:15:25Z - NCEI Accession 0229490 v1.1 was published.
  • 2021-04-17T08:26:53Z - NCEI Accession 0229664 v1.1 was published.
  • 2021-04-19T12:44:11Z - NCEI Accession 0229789 v1.1 was published.
  • 2021-04-21T06:42:59Z - NCEI Accession 0229852 v1.1 was published.
  • 2021-04-23T11:19:00Z - NCEI Accession 0230332 v1.1 was published.
  • 2021-04-25T16:15:58Z - NCEI Accession 0231184 v1.1 was published.
  • 2021-04-27T13:06:53Z - NCEI Accession 0231661 v1.1 was published.
Output Datasets
Acquisition Information (collection)
Instrument
  • AVHRR-2
  • AVHRR-3
Platform
  • NOAA-11
  • NOAA-14
  • NOAA-16
  • NOAA-17
  • NOAA-18
  • NOAA-19
  • NOAA-7
  • NOAA-9
Last Modified: 2021-10-16T01:40:23Z
For questions about the information on this page, please email: ncei.info@noaa.gov