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

FEBRUARY 2010

During February 2010, 439 satellite-tracked surface drifting buoys, 87% with subsurface drogues attached for measuring mixed layer currents, were reporting from the tropical Pacific. The dramatic El Nino-related eastward anomalies seen in the last several months persisted in February. Near-equatorial drifters between the dateline and 160W exhibited eastward anomalies of 30-50 cm/s. Several drifters in the longitude band 140-160W exhibited 20-40 cm/s westward anomalies, with the strongest anomalies measured by a cluster of drifters located between 6S and the equator. Weaker eastward equatorial anomalies were present from 130-160W. Elsewhere, currents were near their climatological average. Across much of the basin, SSTs were close to their climatological February values. Cold SST anomalies (-0.5 to -1.5C) were observed by most drifters in the southeastern corner of the basin, as seen 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.