Mean radiative fluxes and sea surface temperature measured by the five Trop
ical Ocean-Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (
TOGA COARE) boundary layer research aircraft were compared with each other
and with surface measurements from moored buoys and ships. The basic data-p
rocessing techniques for radiative flux and sea surface temperature (SST) m
easurements from an aircraft were reviewed, and an empirical optimisation m
ethod to calibrate an Eppley pyrgeometer was introduced. On the basis of ai
rcraft wingtip-to-wingtip comparison periods, the processed aircraft downwe
lling shortwave and longwave irradiance and SST measurements were found to
agree to 28+/-18 W m(-2), 9+/-4 W m(-2), and 0.7+/-0.4 degrees C, respectiv
ely. By using the same comparison periods, empirical corrections that remov
ed systematic errors in the aircraft data were determined. Application of t
hese corrections improved the wingtip comparison accuracy to 3+/-16 W m(-2)
, 1+/-4 W m(-2), and 0.1+/-0.3 degrees C, respectively. Comparisons between
the (fully corrected) aircraft and the surface platform measurements revea
led the aircraft data to be slightly greater for all three parameters. The
agreement was around 3+/-37 W m(-2), 3+/-6 W m(-2), and 0.3+/-0.5 degrees C
for shortwave irradiance, longwave irradiance, and SST, respectively. (Det
ailed comparison results were provided for each individual ship and buoy.)
After applying the aircraft Empirical corrections the level of accuracy was
near the COARE objectives.