Tropical Pacific Drifting Buoys
Rick Lumpkin / Mayra Pazos, AOML, Miami
During October 2011, 339 satellite-tracked surface drifting buoys, 52% with
subsurface drogues attached for measuring mixed layer currents, were reporting
from the tropical Pacific. Between 110W and the date line, weak equatorial
westward anomalies of O(10 cm/s) were measured by a number of drifters between
the equator and 5S, compared to much stronger anomalies in September. Many
drifters west of the date line and between 20S-20N measured SSTs cooler by 0.5
to 1.5C than the climatological October value.
Top:Movements of drifting buoys in the tropical Pacific Ocean during oct11.
The linear segments of each trajectory represent a one week displacement.
Trajectories of buoys which have lost their subsurface drogues are gray; those with
drogues are black.
Middle: Monthly mean currents calculated from all buoys 1993-2002 (gray),
and currents measured by the drogued buoys this month (black) smoothed by an
optimal filter.
Bottom: Anomalies from the climatological monthly mean currents for this month.