Tropical Pacific Drifting Buoys
Rick Lumpkin / Mayra Pazos, AOML, Miami
During October 2009, 413 satellite-tracked surface drifting buoys, 79%
with subsurface drogues attached for measuring mixed layer currents,
were reporting from the tropical Pacific. Eastward anomalies of ~20 cm/s
were observed by a number of drifters across the basin in the band 0-2S,
with large anomalies of both sides superimposed due to the presence of TIWs.
Most drifters in the Kuroshio Current and recirculation region measured SST
warmer by +0.5 to +3.0C, and many east of 130W in the band 10N-20S measured
SST warmer by +0.5 to +1.5C. Elsewhere, drifters across the basin measured
SST near normal climatological October values.
a) Top: Movements of drifting buoys in the tropical Pacific Ocean.
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 blue.
b) Middle: Monthly mean currents calculated from all buoys 1993-2002 (gray),
and currents measured by the drogued buoys this month (black) smoothed by an
c) Bottom: Anomalies from the climatological monthly mean currents for this month.