Page Overview & Data Sources

• This page provides time series and map visualizations of monthly mean Sea Surface Temperature (SST) and SST anomaly from NOAA Optimum Interpolation SST (OISST) version 2.1. OISST is a 0.25°x0.25° gridded dataset with temperature estimates based on a blend of satellite, ship, and buoy observations for the period September 1981 to present. The SST anomalies are in reference to 1991–2020 climatology, which is the current 30-year climate normal recognized by NOAA and the World Meteorological Organization. Learn more about the OISST, including strengths and limitations, from the NCAR Climate Data Guide.
  
  NOTE: The monthly temperatures displayed here are estimates specific to OISST, and any apparent record high or low values in OISST should be considered with caution and evaluated against other datasets. For long-term global climate time series, refer to NOAA's National Centers for Environmental Information (NCEI) Climate at a Glance with monthly means of surface temperature observations 1850 to present.


• Time series and maps: The time series chart displays area-weighted means for the selected domain. For example, if World 60S-60N is selected, then each daily SST value on the chart represents the average of all ocean gridcells between 60°S and 60°N across all longitudes, and accounts for the convergence of longitudes at the poles.
  
  World (60°S–60°N, 0–360°E) North Atlantic (0–60°N, 0–80°W) Subpolar North Atlantic (45–60°N, 20–45°W) Atlantic Hurricane MDR* (10–20°N, 20–85°W) Gulf of Maine (42–45°N, 66–71°W) Gulf of Mexico (20–30°N, 82–98°W) Niño 3.4 (5°S–5°N, 120–170°W)
  *MDR = Main Development Region
  The map below the chart can be updated by either moving the Image Slider or hovering the cursor over a data point on the time series chart. Switch between SST and SST anomaly from the variable dropdown menu. A sea ice mask is applied to the SST and anomaly maps for gridcells where ice concentration is >= 50%.


• NCAR Command Language is used for data processing and map generation. The interactive time series chart is made using HighCharts. OISST data grids can be downloaded from NCEI here.

Last updated 1 October 2024