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

JANUARY 2010

During January 2010, 426 satellite-tracked surface drifting buoys, 86% with subsurface drogues attached for measuring mixed layer currents, were reporting from the tropical Pacific. The dramatic basinwide El Nino-related eastward anomalies seen in the last few months had become less prominent in January. West of the dateline, near-equatorial drifters exhibited eastward anomalies of ~50 cm/s, moving eastward where the climatological January current is westward, while several drifters in the longitude band 140-160W exhibited 20-40 cm/s westward anomalies. Elsewhere, currents were near their climatological average, although they indicated that the NECC was shifted two degrees south of its normal position across a broad stretch of the basin. Hot equatorial SST anomalies of +0.5 to +3.0C were measured by most drifters in the region 100W-170E, 20S-10N. Cold SST anomalies (-0.5 to -3.0C) were observed in the southeastern corner of the basin as in previous months.

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.