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

AIRCRAFT LOGISTICS AND DRIFTING BUOY COVERAGE
FOR THE FIRST GARP GLOBAL EXPERIMENT
Pat Martin
AIDJEX
There has been a shift of emphasis in the plans for distribution of
drifting data buoys in FGGE away from the Antarctic convergence and toward
the tropics in response to the elimination of the carrier balloon/dropsonde
program from the observing system. Early plans had called for 300 buoys to
be deployed between latitudes 55's and 65's to collect surf ace temperature
and pressure data not available from satellite soundings due to the persistent
cloudinessin that region. Recent deployment plans emphasize coverage
of temperate latitudes (3OoS-55'S) and have very sparse coverage south of
55OS (Fig. 1). The hope of polar scientists to have significant new data in
conjunction with FGGE is not reflected in FGGE data buoy plans.
The schedule for buoy deployments reflects a heavy emphasis on the first
special observing period (SOP) in the austral summer (Fig. 2). Of the 240
buoys covered in the current plans, 185 are scheduled to be deployed before
May 1979 and 55 after that. The few deployments in May and June which could
be effective in producing good coverage of the effects of the Antarctic winter
on the Southern Ocean are, instead, to be deployed primarily between 20's and
4OoS, as seen in the hatched area of Figure 1. In this respect the FGGE is
rapidly becoming a rare opportunity lost to polar science. For the first
(and perhaps only) time the observing system in the Southern Hemisphere will
be reasonably complete, except for the ocean south of the Antarctic convergence
and especially in the austral winter.
This unfortunate situation came about in part because polar scientists
were not aware of the extent to which the shift to lower latitudes would
dilute high latitude coverage and did not press decisions for a higher priority
on polar coverage or establish independent programs. The shift of
emphasis to mid-lat5tudes and summer was also necessitated by the availability
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