The EUSTACE dataset, 'Global land station daily air temperature measurements with non-climatic discontinuities applied, for 1850-2015', has been produced by bringing together daily maximum and minimum temperatures from various public databases (GHCN-D, ECA&D, DECADE, ISTI and ERA-CLIM). These data have then been quality controlled through the removal of duplicates and unreliable data sources, and were assessed for homogenity by applying tests to look for breakpoints in the time series.
The data were also assessed to provide a rough estimation of the reporting resolution for each year in the series.

For further details see the EUSTACE product user guide.

The following datasets have been used as input:
Global Historical Climatology Network (GHCN)-Daily v3.22 (Menne, M. J., Durre, I., Vose, R. S., Gleason, B. E., & Houston, T. G. (2012). An overview of the global historical climatology network-daily database. Journal of Atmospheric and Oceanic Technology, 29(7), 897-910.); European Climate Assessment & Dataset (ECA&D) – October 2016 update (Klein-Tank, A., Wijngaard, J. B., Können, G. P., Böhm, R., Demarée, G., Gocheva, A., et al. (2002). Daily dataset of 20th‐century surface air temperature and precipitation series for the European Climate Assessment. International Journal of Climatology, 22(12), 1441-1453.); International Surface Temperature Initiative (ISTI) v1.00 (Rennie, J. J., Lawrimore, J. H., Gleason, B. E., Thorne, P. W., Morice, C. P., Menne, M. J., et al. (2014). The international surface temperature initiative global land surface databank: Monthly temperature data release description and methods. Geoscience Data Journal, 1(2), 75-102.); Project DECADE (Hunziker, S., Gubler, S., Calle, J., Moreno, I., Andrade, M., Velarde, F., et al. (2017). Identifying, attributing, and overcoming common data quality issues of manned station observations. International Journal of Climatology, 37(11), 4131-4145.); Projects ERA-CLIM / ERA-CLIM2 (Stickler, A., Brönnimann, S., Valente, M. A., Bethke, J., Sterin, A., Jourdain, S., et al. (2014). ERA-CLIM: historical surface and upper-air data for future reanalyses. Bulletin of the American Meteorological Society, 95(9), 1419-1430.)