GISTEMP v4¶

GISS Surface Temperature Analysis, version 4

Available

At a glance¶

Note on period: Under the GISS 2026 release schedule, the September 2026 data were due on 2026-10-09. We could not open the tables (tabledata_v4) during this check, so the latest month has not been confirmed. Each monthly update can also revise earlier months as late reports and corrections arrive.

Overview¶

The GISS Surface Temperature Analysis version 4 (GISTEMP v4) is an estimate of global surface temperature change since 1880. It combines NOAA GHCN v4 meteorological station data over land with ERSST v5 over ocean areas, following Hansen et al. (2010) and Lenssen et al. (2024), and reports anomalies relative to the 1951–1980 means. Station anomalies are spread over a 1200 km radius, so sparsely observed regions such as the Arctic are filled. A 200-member observational uncertainty ensemble (1880–2020) is also available.

Available variables¶

Products as listed on the official Data Downloads page. We could not open the NetCDF files during this check, so the variable names inside them are not given here (run ncdump -h after downloading).

instantaneous mean accumulated maximum minimum static — instantaneous: value at the time stamp · mean/accumulated/maximum/minimum: over the indicated interval · static: does not change with time

Gridded data (regular 2°×2° grid, NetCDF and Zarr)¶

Summary tables (L-OTI, plain text and CSV)¶

Observational uncertainty ensemble (Lenssen et al. 2024)¶

The full variable list is in the official documentation.

How to get the data¶

• GISTEMP Data Downloads — HTTPS (browser / wget / curl) No login needed
  • Summary tables (tabledata_v4/GLB.Ts+dSST.csv etc.), gzip-compressed 2°×2° NetCDF and Zarr v3 (tar.gz) files, the basic SBBX files and Fortran code to read them. Gridded files live under https://data.giss.nasa.gov/pub/gistemp/.
• Observational uncertainty ensemble v2.0 — HTTPS
  • The full 200-member ensemble (16 ZIP archives of about 700 MiB each), KeySeries.zip, GriddedSummary.zip and R analysis code. Some downloads ask for the shared user ID and password given on the page. The NetCDF files were updated on 2024-10-01 to fix a minor error in labelling the time dimension.
• Station data — Web tool No login needed
  • Browse and download raw and adjusted records for individual stations.
• GISTEMP source code — HTTPS (tar.gz)

Example code¶

Downloads the 1200 km LOTI grid and computes an area-weighted global mean. Open the file first and adjust variable and coordinate names if needed (the code below picks the first time-lat-lon variable automatically).

import gzip, shutil, urllib.request
import numpy as np
import xarray as xr

url = "https://data.giss.nasa.gov/pub/gistemp/gistemp1200_GHCNv4_ERSSTv5.nc.gz"
urllib.request.urlretrieve(url, "gistemp1200.nc.gz")
with gzip.open("gistemp1200.nc.gz") as fi, open("gistemp1200.nc", "wb") as fo:
    shutil.copyfileobj(fi, fo)

ds = xr.open_dataset("gistemp1200.nc")
print(ds)                                         # check variable/coordinate names and units
name = [v for v in ds.data_vars if ds[v].ndim == 3][0]
da = ds[name]                                     # monthly anomalies vs 1951-1980
tdim, ydim, xdim = da.dims
w = np.cos(np.deg2rad(da[ydim]))
glob = da.weighted(w).mean([ydim, xdim])
print(glob.isel({tdim: slice(-12, None)}).round(2).to_series())

Practical tips¶

• Anomalies are relative to 1951–1980, so they look warmer than HadCRUT5 (1961–1990). Rebase to a common period before comparing datasets.
• The 1200 km product extends station information far into the Arctic and the Antarctic interior. When interpreting polar results, check them against the 250 km land product and the station coverage.
• As of October 2026 the ocean input is ERSST v5. NOAA adopted ERSST v6 in 2026 and has announced the end of v5; if GISTEMP switches its ocean input, values for the whole record may change. Keep an eye on the Updates to Analysis page.
• Monthly updates revise past values, so record your download date and archive the files you used (the GISS citation includes an access date).
• The uncertainty ensemble (v2.0) covers 1880–2020 only and is not updated monthly. For recent years, use the FAQ's rough figure (about ±0.05°C for annual global means after 1960).
• GISS removes faulty station reports as they are found and reports them to NOAA (e.g. three Maliye Karmakuly reports dropped in September 2025). For regional or station-level work, check the Updates to Analysis log.

Notices and change history¶

References for your paper¶

Dataset citation¶

GISTEMP dataset (as recommended by GISS)

@misc{gistemp_v4_dataset,
  author       = {{GISTEMP Team}},
  title        = {{GISS} Surface Temperature Analysis ({GISTEMP}), version 4},
  year         = {2026},
  publisher    = {NASA Goddard Institute for Space Studies},
  howpublished = {\url{https://data.giss.nasa.gov/gistemp/}},
  note         = {Dataset accessed YYYY-MM-DD}
}

Reference papers¶

GISTEMP v4 observational uncertainty ensemble (the latest publication GISS asks you to cite) — DOI 10.1029/2023JD040179

@article{lenssen2024gistemp,
  author  = {Lenssen, Nathan and Schmidt, Gavin A. and Hendrickson, Michael and Jacobs, Peter and Menne, Matthew J. and Ruedy, Reto},
  title   = {A {NASA} {GISTEMPv4} Observational Uncertainty Ensemble},
  journal = {Journal of Geophysical Research: Atmospheres},
  volume  = {129},
  number  = {17},
  pages   = {e2023JD040179},
  year    = {2024},
  doi     = {10.1029/2023JD040179}
}

Improvements in the GISTEMP uncertainty model (introduced v4) — DOI 10.1029/2018JD029522

@article{lenssen2019gistemp,
  author  = {Lenssen, Nathan J. L. and Schmidt, Gavin A. and Hansen, James E. and Menne, Matthew J. and Persin, Avraham and Ruedy, Reto and Zyss, Daniel},
  title   = {Improvements in the {GISTEMP} Uncertainty Model},
  journal = {Journal of Geophysical Research: Atmospheres},
  volume  = {124},
  number  = {12},
  pages   = {6307--6326},
  year    = {2019},
  doi     = {10.1029/2018JD029522}
}

GISTEMP analysis method (combining land and ocean) — DOI 10.1029/2010RG000345

@article{hansen2010gistemp,
  author  = {Hansen, J. and Ruedy, R. and Sato, M. and Lo, K.},
  title   = {Global Surface Temperature Change},
  journal = {Reviews of Geophysics},
  volume  = {48},
  number  = {4},
  pages   = {RG4004},
  year    = {2010},
  doi     = {10.1029/2010RG000345}
}

Acknowledgements¶

GISS asks you to cite both the webpage (GISTEMP Team, with your access date) and its most recent scholarly publication, Lenssen et al. (2024). The preferred credit is "NASA's Goddard Institute for Space Studies", or "NASA GISS/GISTEMP" where space is limited. There is no dataset DOI; if you use the uncertainty ensemble, also cite Zenodo DOI 10.5281/zenodo.13343335.

Information on the datasets used in this study was compiled with the help of the Korean Climate Data Navigator (KCDN) (Sim, 2026; https://doi.org/10.5281/zenodo.23300923).

Links¶

• GISTEMP home (NASA GISS)
• GISTEMP Data Downloads
• Updates to Analysis (change log)
• Release Dates Schedule
• GISTEMP FAQ
• Observational uncertainty ensemble
• NOAA GHCN-Monthly (land input)
• NOAA ERSST (ocean input)