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

JUNE 2009

During June 2009, 355 satellite-tracked surface drifting buoys, 72% with subsurface drogues attached for measuring mixed layer currents, were reporting from the tropical Pacific. North of 10S, eastward anomalies have intensified since last month, with magnitudes of 10-20 cm/s now seen across the basin. In the narrow band of the NECC at 10N, weak westward anomalies were measured by several drifters. From 10-22S, westward anomalies of O(10 cm/s) were common across the basin. Most drifters away from the northwest corner of the region measured SST at or above normal June values, with anomalies of +0.5 to +1.5C very common. Warm anomalies were especially prevalent in the southeast tropical Pacific. Cold anomalies (-0.5C to -3.0C) were measured by many drifters in the northwest, north of 20N and west of the dateline. These SST anomaly patterns have persisted over the previous several 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.