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NOAA Smith and Reynolds Extended Reconstructed Sea Surface Temperature (ERSST) Level 4 Monthly Version 4 Dataset in netCDF. DOI:

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NOAA Smith and Reynolds Extended Reconstructed Sea Surface Temperature (ERSST) Level 4 Monthly Version 4 Dataset in netCDF

1 Publication Cited this Dataset
Citation metrics available for years (2014-2021)
DescriptionThe Smith & Reynolds Extended Reconstructed Sea Surface Temperature (ERSST) Level 4 dataset provides a historical reconstruction of monthly global ocean surface temperatures and temperature anomalies over a 2 degree spatial grid since 1854 from in-situ observations based on a consistent statistical methodology that accounts for uneven sampling distributions over time and related observational biases. Version 4 of this dataset implements release 2.5 of ICOADS (International Comprehensive Ocean-Atmosphere Data Set) and is supplemented by monthly GTS (Global Telecommunications Ship and buoy) system data. As for the prior ERSST version, v4 implements Empirical Orthogonal Teleconnection analysis (EOT) but with an improved tuning method for sparsely sampled regions and periods. ERSST anomalies are computed with respect to a 1971-2000 monthly climatology. The version 4 has been improved from previous version 3b. Major revisions include updated and substantially more complete input data from the ICOADS release 2.5, revised EOTs and EOT acceptance criterion, updated SST quality control procedures, revised SST anomaly evaluation methods, updated bias adjustments of ship SSTs using the Hadley Centre Nighttime Marine Air Temperature dataset version 2 (HadNMAT2), and buoy SST bias adjustment not previously made in v3b. The ERSST v4 in netCDF format contains extended reconstructed sea surface temperature, SST anomaly, and associated estimated SST error standard deviation fields, incompliance with CF1.6 standard metadata.
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Citation is critically important for dataset documentation and discovery. Please cite the data as follows, and cite the reference papers when it is appropriate.
Citation Smith, T., Reynolds, R.. 1981. NCDC Smith & Reynolds Historical Reconstructed Sea Surface Temperature Data Sets. Ver. 4. PO.DAAC, CA, USA. Dataset accessed [YYYY-MM-DD] at

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For more information see Data Citations and Acknowledgments.

Journal Reference Smith, T.M., R.W. Reynolds, Thomas C. Peterson, and Jay Lawrimore, 2008: Improvements to NOAA's Historical Merged Land-Ocean Surface Temperature Analysis (1880-2006). Journal of Climate,21, 2283-2296.