Global Surface Temperature Anomalies

The global time series is produced from the Smith and Reynolds blended land and ocean data set (Smith et al., 2008). Global-average anomalies are calculated on an annual time scale. The global anomalies are provided with respect to the period 1901-2000, the 20th century average.

Land surface temperatures are from the Global Historical Climate Network-Monthly (GHCN-M). Sea surface temperatures are determined using the extended reconstructed sea surface temperature (ERSST) analysis. ERSST uses the most recently available International Comprehensive Ocean-Atmosphere Data Set (ICOADS) and statistical methods that allow stable reconstruction using sparse data. Due to very sparse data, no global averages are computed before 1880. With more observations after 1880, the signal is stronger and more consistent over time.

The Global Anomalies and Index Data

@us-noaa/gsta/1880-2021_Annual_Global_Land.csv
@us-noaa/gsta/1880-2021_Annual_Global_Ocean.csv
@us-noaa/gsta/1880-2020_Annual_Global_LandAndOcean.csv
@us-noaa/gsta/1880-2021_Monthly_Global_Land.csv
@us-noaa/gsta/1880-2021_Monthly_Global_Ocean.csv
@us-noaa/gsta/1880-2021_Monthly_Global_LandAndOcean.csv
@us-noaa/gsta/1880-2021_Monthly_NorthernHemisphere_Ocean.csv
@us-noaa/gsta/1880-2021_Monthly_NorthernHemisphere_Land.csv
@us-noaa/gsta/1880-2021_Monthly_NorthernHemisphere_LandAndOcean.csv
@us-noaa/gsta/1880-2021_Monthly_SouthernHemisphere_Land.csv
@us-noaa/gsta/1880-2021_Monthly_SouthernHemisphere_Ocean.csv
@us-noaa/gsta/1880-2021_Monthly_SouthernHemisphere_LandAndOcean.csv

Annual time series are not available for Northern/Southern Hemisphere (only Global). Anomalies are with respect to the 20th century average (1901-2000). Monthly and annual global anomalies are available through the most recent complete month and year, respectively.

Global Mean Monthly Surface Temperature Estimates for the Base Period 1901 to 2000

Please see the table on the NOAA website.

Gridded Dataset

To obtain a copy of the monthly average temperature anomalies on a 5° x 5° grid across land and ocean surfaces, please see https://www.ncdc.noaa.gov/monitoring-references/faq/anomalies.php#grid or use the following information to access anonymous FTP at NCEI:

Machine Address: ftp.ncdc.noaa.gov Login Name: anonymous Password: your email address Directory: /pub/data/ghcn/blended/ Enter: bin Enter: get ncdc-merged-sfc-mntp.dat.gz

For information on the format of the dataset, please visit our Global Historical Climatology Network page. A direct link to the file is also provided on the website.