AIDJEX Bulletin #40 - Polar Science Center - University of Washington

cooling at night. Temperatures are good to about 2OC for wind speeds greater
than 4 m sec-' (Fig. 10). Cloud cover reduced radiation errors in the second
half of the test period.
Internal and external temperature measurement errors with respect to the
NWS data for spring and summer are given in Table 1. Means and standard deviation
of errors in daily averages of the external temperature measurements are
small enough (about l0C) to suggest that daily average temperatures may be
useful. Estimates of errors in daily averages might be weighted according to
wind speeds calculated from the pressure measurements. We have not calculated
such a weighting. Winter temperatures would be expected to be consistently
too low due to constant radiative cooling and low wind speeds during that
season. Under these conditions, it is also possible for a cold surface layer
1-2 m thick to form, which would limit the value of winter temperature
measurements. It is possible that daily averages of the internal buoy
temperature would be useful under these and other conditions, especially if
the radiation sensitivity of the buoy itself could be reduced.
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