The data are here.
The following is an excerpt from the 'readme' file associated with this data set.
Extended Reconstructed Sea Surface Temperatures, version 2 (ERSST.v2), beginning January 1854. ERSST.v2 is an improved extended reconstruction of SST. In both version 1 and version 2 the high-frequency SST anomalies are reconstructed by fitting to a set of spatial modes. In version 1 anomaly increments are reconstructed using anomaly increment modes. In version 2 anomalies are reconstructed using anomaly modes. In regions where variance is relatively large the two are comparable, but version 2 better analyzes the anomalies in regions where the variance is low. In addition, version 2 also uses sea-ice concentrations to improve the high-latitude SST analysis, and a modified historical bias correction for the 1939-1941 period. Version 2 also includes an improved error estimate. Data are available in this directory. All fields were computed on the 2-degree grid. The grid has 180 zonal points on 0E, 2E, ..., 358E, and 89 meridional points on 88S, 86S, ..., 88N. Over land a value of -99.99 is assigned. In addition any SST mean value less than -1.8C was set to -1.8C.
References:
Smith, T.M., and R.W. Reynolds, 2004: Improved Extended Reconstruction of SST (1854-1997). Journal of Climate, 17, (in press)
Thomas M. Smith (e-mail: Tom.Smith@noaa.gov)
National Climate Data Center
4115 Computer and Space Sciences Building
University of Maryland
College Park, MD 20742-2465 USA
Richard W. Reynolds (e-mail: Richard.W.Reynolds@noaa.gov)
National Climate Data Center
151 Patton Ave., Room 514,
Asheville, NC 28801