Tropical Pacific Drifting Buoys
Rick Lumpkin / Mayra Pazos, AOML, Miami
During July 2014, 332 satellite-tracked surface drifting buoys, 91% with
subsurface drogues attached for measuring mixed layer currents, were reporting
from the tropical Pacific. The strong westward anomalies seen in the eastern
equatorial Pacific in June persisted in July, with a monthly average of as much
as 50 cm/s westward compared to climatological July values. Not enough
drifters were located in the western near-equatorial Pacific to determine the
zonal extent of these anomalies. At higher latitudes, currents were near their
climatological July strengths.
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 1993-2010 (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.