Download: Observations

The following observation datasets are available.

• ENSO Indices : monthly NINO1+2, NINO3, NINO3.4 and NINO4 area-averaged sea-surface temperatures (SSTs) from 1856 to date using the Kaplan extended SST data . The data are typically updated towards the end of the first week of each month. The areas are:
  • NINO1+2 : 0-10S, 90W-80W
  • NINO3 : 5N-5S, 150W-90W
  • NINO3.4 : 5N-5S, 170W-120W
  • NINO4 : 5N-5S, 160E-150W
• SST : Two datasets are available:
  • 2- by 2-degree SSTs from 1854 (for most analyses it is not recommended to use data prior to about 1950) to date from the Extended Reconstructed Sea-Surface Temperature (ERSST) dataset - version 5 of the dataset is accessed in CPT16 and later versions. The data are typically updated towards the middle or end of the first week of each month. This dataset does not require a password.
  • 0.25- by 0.25-degree SSTs from October 1981 to date from the Optimal Interpolated Sea-Surface Temperature (OISST) dataset - version 2.1 of the dataset is accessed in CPT17.8 and later versions. This dataset does not require a password.
• Maximum Temperature : Two datasets are available:
  • 0.5- by 0.5-degree maximum air temperatures over land from 1901 to 2020 from the University of East Anglia Climate Research Unit (CRU) gridded station dataset. Version 4.05 of the dataset is accessed in CPT17.6 and later versions. This dataset is password protected. See information on getting permission for further details.
  • 0.05- by 0.05-degree maximum air temperatures over land from 1983 to 2016 from the Climate Hazards Center Infrared Temperature with Stations (CHIRTS) dataset. Version 1 of the dataset is accessed in CPT17.3.2 and later versions. Monthly averages are calculated from daily data. This dataset is not password protected.
• Minimum Temperature : Two datasets are available:
  • 0.5- by 0.5-degree minimum air temperatures over land from 1901 to 2020 from the University of East Anglia Climate Research Unit (CRU) gridded station dataset. Version 4.05 of the dataset is accessed in CPT17.6 and later versions. This dataset is password protected. See information on getting permission for further details.
  • 0.05- by 0.05-degree maximum air temperatures over land from 1983 to 2016 from the Climate Hazards Center Infrared Temperature with Stations (CHIRTS) dataset. Version 1 of the dataset is accessed in CPT17.3.2 and later versions. Monthly averages are calculated from daily data. This dataset is not password protected.
• Mean Temperature : 0.5- by 0.5-degree mean air temperatures over land from 1901 to 2020 from the University of East Anglia Climate Research Unit gridded station dataset. Version 4.05 of the dataset is accessed in CPT17.6 and later versions. This dataset is password protected. See information on getting permission for further details.
• Precipitation : Four datasets are available:
  • 0.5- by 0.5-degree precipitation over land from 1901 to 2020 from the University of East Anglia Climate Research Unit (CRU) gridded station dataset. Version 4.05 of the dataset is accessed in CPT17.6 and later versions. This dataset is password protected. See information on getting permission for further details.
  • 0.5- by 0.5-degree precipitation over land from 1891 to 2019 from the Global Precipitation Climatology Centre . Version 2020 of the dataset is accessed in version 17.8 and later. This dataset does not require a password.
  • 0.05- by 0.05-degree precipitation over land from 1981 to date from the Climate Hazards Center Infrared Precipitation with Stations (CHIRTS) dataset. Version 2.0 of the dataset is accessed in CPT15.6.2 and later versions. This dataset is not password protected.
  • 1- by 1-degree precipitation over land from 1981 to date from the Climate Hazards Center Infrared Precipitation with Stations (CHIRTS) dataset. Version 2.0 of the dataset is accessed in CPT17.3.2 and later versions. This dataset is not password protected.
• Wet-days : 0.5- by 0.5-degree wet-days over land from 1901 to 2020 from the University of East Anglia Climate Research Unit gridded station dataset. Version 4.05 of the dataset is accessed in CPT17.6 and later versions. This dataset is password protected. See information on getting permission for further details.