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

APRIL 2008

During April 2008, 308 satellite-tracked surface drifting buoys, 80% 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, persisted in April. Strong (20-30 cm/s) eastward anomalies were measured by several near-equatorial drifters at 140-150W. Cold SST anomalies (-0.5 to -3.0C) were measured by many drifters in the central Pacific (140W to the dateline), while warm anomalies (+0.5 to +1.5C) were measured in the southeast, southwest and northwest edges of the 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.