Observing System Monitoring Center

Observational Density

Presented here are figures of valid in situ observations of SST, SLP, air temp, wind speed/direction, dew point and cloud cover as obtained from ships, moored and drifting buoys. To see a time-series, click times-series, the minimum number of observations per 5x5 degree grid box, the variable and set the year menu to "Time Series." For a global view by year, click shaded figure, minimum number of observations, the variable and the year from the drop down menu. If you get a page with no figure, you may have setup the figure constraints wrong.

NOTE: Accuracy weighted ship observational density measurements are included in the source options, but are only applied to SST observations. These accuracy weighted ship observational measurments were computed by adjusting the ship observational density by the relative accuracy of ships. A 1/6 scaling factor is used, since the RMS from ship observations is 2.5 that from buoy observations [Reynolds, personal communication 2003].

Time-Series Color Key


Time Series
Global View - shaded
Global View - smooth contour


Min number of obs



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Dept of Commerce / NOAA / OAR / PMEL / TMAP