GISS Surface Temperature Analysis (GISTEMP v4)
The GISS Surface Temperature Analysis version 4 (GISTEMP v4) is an estimate of global surface temperature change. Graphs and tables are updated around the middle of every month using current data files from NOAA GHCN v4 (meteorological stations) and ERSST v5 (ocean areas), combined as described in our publications Hansen et al. (2010) and Lenssen et al. (2019). These updated files incorporate reports for the previous month and also late reports and corrections for earlier months.
News and Updates
Sep. 14, 2023: NASA has posted a news release about the Summer (JJA) 2023 global temperature anomaly.
Aug. 14, 2023: NASA has posted a news release about the July 2023 global temperature anomaly.
Mar. 14, 2023: The source NOAA ocean temperatures OISST v2 are no longer updated. These data were based on satellite data and they were used in some displays as an added alternative to our standard ocean data, which are based on ship and buoy data. Currently, these data are no longer available.
See the GISTEMP News page for a list of announcements and NASA articles related to the GISTEMP analysis. Announcements when our monthly updates are released are posted to the NASA/GISS Twitter feed.
See the Updates to Analysis page for detailed update information about GISTEMP v4.
Contacts/Personnel
Before contacting us, please check if your question about the GISTEMP analysis is already answered in the FAQ.
If the FAQ does not answer your question, please address your inquiry to Dr. Reto Ruedy.
Other researchers currently participating in the GISTEMP analysis include Michael Hendrickson, Maxwell Elling, Dr. Makiko Sato, and Dr. Nathan Lenssen.
The GISTEMP analysis was initiated by Dr. James E. Hansen, now retired. It is currently led by Dr. Gavin Schmidt.
Past members on the GISTEMP team have included Dr. Sergej Lebedeff, Dr. Helene Wilson, Jay Glascoe, Avraham Persin, Dr. Ken Lo, and others. We also thank Nick Barnes et al. at the Clear Climate Code project for their contributions.
Citation
When referencing the GISTEMP v4 data provided here, please cite both this webpage and also our most recent scholarly publication about the data. In citing the webpage, be sure to include the date of access.
- GISTEMP Team, 2023: GISS Surface Temperature Analysis (GISTEMP), version 4. NASA Goddard Institute for Space Studies. Dataset accessed 20YY-MM-DD at https://data.giss.nasa.gov/gistemp/.
- Lenssen, N., G. Schmidt, J. Hansen, M. Menne, A. Persin, R. Ruedy, and D. Zyss, 2019: Improvements in the GISTEMP uncertainty model. J. Geophys. Res. Atmos., 124, no. 12, 6307-6326, doi:10.1029/2018JD029522.
Background, History and Updates
The basic GISS temperature analysis scheme was defined in the late 1970s by James Hansen when a method of estimating global temperature change was needed for comparison with one-dimensional global climate models. The analysis method was fully documented in Hansen and Lebedeff (1987). Several papers describing updates to the analysis followed over the following decades, most recently that of Hansen et al. (2010), as well as the uncertainty quantification of Lenssen et al. (2019).
For further details, please see the GISTEMP Background, History, and References pages. We also maintain a running record of modifications made to the analysis on our Updates to Analysis page.
The GISTEMP analysis is updated regularly. Graphs and tables are posted around the middle of every month using the latest GHCN and ERSST data. The update incorporates reports for the previous month as well as late reports and corrections for earlier months.
Source Code
Programs used in the GISTEMP analysis and documentation on their use are available for download. The programs assume a Unix-like operating system and require familiarity with Python for installation and use.
Tables of Global and Hemispheric Monthly Means and Zonal Annual Means
Combined Land-Surface Air and Sea-Surface Water Temperature Anomalies (Land-Ocean Temperature Index, L-OTI)
The following are plain-text files in tabular format of temperature anomalies, i.e. deviations from the corresponding 1951-1980 means.
- Global-mean monthly, seasonal, and annual means, 1880-present, updated through most recent month: TXT, CSV
- Northern Hemisphere-mean monthly, seasonal, and annual means, 1880-present, updated through most recent month: TXT, CSV
- Southern Hemisphere-mean monthly, seasonal, and annual means, 1880-present, updated through most recent month: TXT, CSV
- Zonal annual means, 1880-present, updated through most recent complete year: TXT, CSV
AIRS v6 and AIRS v7 Temperature Anomalies
The following tables show anomalies based on AIRS data vs. 2007-2016. Corresponding L-OTI anomaly data are also provided.
- Global-mean monthly, seasonal, and annual means, 2002-present, updated through most recent month: TXT, CSV
- Northern Hemisphere-mean monthly, seasonal, and annual means, 2002-present, updated through most recent month: TXT, CSV
- Southern Hemisphere-mean monthly, seasonal, and annual means, 2002-present, updated through most recent month: TXT, CSV
- Zonal annual means, 2002-present, updated through most recent complete year: TXT, CSV
Gridded Monthly Temperature Anomaly Data
Users interested in the entire gridded surface air temperature anomaly data may download netCDF files containing selected series on a regular 2°×2° grid or the basic SBBX binary files.
Compressed NetCDF Files (regular 2°×2° grid)
- Land-Ocean Temperature Index, ERSSTv5, 1200km smoothing (23 MB)
- Surface air temperature (no ocean data), 250km smoothing (9 MB)
- Land Mask on a 2°×2° grid
Compressed Zarr Directories (regular 2°×2° grid)
- Land-Ocean Temperature Index, ERSSTv5, 1200km smoothing (53 MB)
- Surface air temperature (no ocean data), 250km smoothing (27 MB)
Compressed Basic Subbox Grid Series (equal-area grid)
- Surface air temperature, 1200km smoothing - GISTEMP v4 (27 MB)
- Surface air temperature, 250km smoothing - GISTEMP v4 (9 MB)
- Sea surface air temperature (ERSSTv5), currently used (30 MB)
- Sea surface air temperature (ERSSTv4), used until July 2017 (30 MB)
- Sea surface air temperature (ERSSTv3b), used until June 2015 (30 MB)
- Sea surface air temperature (HadR2), used until Nov. 2012 (30 MB)
Also available are various FORTRAN programs and instructions to create (time series of) regular gridded anomaly maps from the basic files. Be sure to read the README file for discussion of the files' binary format.
References
Please see the GISTEMP references page for citations to publications related to this research. Copies of many of our papers are available in the GISS publications database.
