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

A TEST OF BAROMETRIC
PRESSURE AND TEMPERATURE MEASUREMENTS
FROM ABRAMS BUOYS
Pat
Martin and Me1 Clarke
AIDJEX
ABSTRACT
Two buoys were tested for four months in 1977 at Barrow, Alaska,
to resolve questions important to the measurement of barometric
pressure and temperature from surface buoys in polar regions.
The internal temperature stability was improved by insulating
the buoy hull. Temperature effects on the barometric sensor and
on the buoy clock were investigated. The barometers were free
from drift over the four-month period. An air temperature sensor
was found to be sensitive to radiation effects except when aspirated
by the wind. The barometric pressure measurements were
found to have some sensitivity to wind.
INTRODUCTION
In March 1977, two ADRAMS buoys fitted with pressure sensors and both
internal and external temperature sensors were deployed on the tundra at Barrow,
Alaska. Data were taken for about four months and compared with routine.hourly
measurements taken by the National Weather Service (NWS), also at Barrow, only
a few kilometers away. Figure 1 shows the comparison. Since satellite passes,
and therefore buoy measurements, did not occur on the hour, linear interpolation
was used between the hourly NWS samples and buoy measurements. All
barometric pressure data were reduced to sea level according to measured
elevation. Previous experience with the NWS barometric pressure measurements
at Barrow has shown the errors to be 0.2 mb or less.
The four-month test was undertaken to understand better the phenomena
affecting barometric pressure and temperature measurements from ADRAMS (Air
Droppable Random Access Measurement System) buoys [Brown and Kerut, 19761, so
that uniformly good measurements could be obtained in the future without
resorting to field calibrations. Specific areas of difficulty which had to
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