Tropical Highlights

  Table of Atmospheric Indices  (Table 1)

  Table of Oceanic Indices  (Table 2)

  Time Series

  Time-Longitude Sections

  Mean & Anomaly Fields

  Appendix 1: Outside Contributions

• Tropical Drifting Buoys  A1.1
  
• Thermistor Chain Data  A1.2
  
• TAO/TRITON Array (a)  A1.3
  
• TAO/TRITON Array (b)  A1.4
  
• East Pac. SST & Sea Level  A1.5
  
• Pacific Wind stress  A1.6
  
• Surface Currents (a)  A1.7
  
• Surface Currents (b)  A1.8
  
  

Tropical Pacific Drifting Buoys

Rick Lumpkin / Mayra Pazos, AOML, Miami

MAY 2008

During May 2008, 325 satellite-tracked surface drifting buoys, 81% with subsurface drogues attached for measuring mixed layer currents, were reporting from the tropical Pacific. The westward anomalies over most of the basin, seen in the previous several months, weakened in May. Strong (20-30 cm/s) eastward anomalies were measured by some near-equatorial drifters at 120-140W, east of where eastward anomalies were observed in April. Cold SST anomalies (-0.5 to -3.0C) were measured by most drifters in the central Pacific (170E to the 130W) at 5N to 15N, while warm anomalies (+0.5 to +1.5C) were measured in the southeastern and southern (below 10S) tropical Pacific basin.

FIGURE A1.1 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 optimal filter. c) Bottom: Anomalies from the climatological monthly mean currents for this month.