Ec. Kent et al., A statistical determination of the random observational errors present in voluntary observing ships meteorological reports, J ATMOSP OC, 16(7), 1999, pp. 905-914
The random observational errors for meteorological variables within the Com
prehensive Ocean-Atmosphere Dataset (COADS) have been determined using the
semivariogram statistical technique. The error variance has been calculated
using four months of data, spanning summer and winter months and the start
and end of the dataset. The random errors found range from 1.3 to 2.8 m s(
-1) for 10-m-corrected wind speed, 1.2 to 7.1 mb for surface pressure, 0.8
degrees to 3.3 degrees C for 10-m air temperature, 0.4 degrees to 2.8 degre
es C for sea surface temperature, and 0.6 to 1.8 g kg(-1) for 10-m specific
humidity. The air temperature and specific humidity random observational e
rrors contain a dependence on their mean values, but correlations between e
rrors and mean Values are low for the other variables analyzed. The accurac
y of the error estimates increases with the number of observational data pa
irs used in the analysis. Wind speed random observational errors were reduc
ed by height correction and by the use of the Lindau Beaufort Scale.
Taken over the latitude range 45 degrees S-75 degrees N, the mean random ob
servational errors are 2.1 +/- 0.2 m s(-1) for 10-m-corrected wind speed, 2
.3 +/- 0.2 mb for surface pressure, 1.4 degrees +/- 0.1 degrees C for 10-m
air temperature, 1.5 degrees +/- 0.1 degrees C for sea surface temperature,
and 1.1 +/- 0.2 g kg(-1) for 10-m specific humidity.