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
  
• Pacific Wind stress  A1.2
  
• Surface Currents (a)  A1.3
  
• Surface Currents (b)  A1.4
  
  

Tropical Pacific Drifting Buoys

Rick Lumpkin / Mayra Pazos, AOML, Miami

JANUARY 2013

During January 2013, 325 satellite-tracked surface drifting buoys, 82% with subsurface drogues attached for measuring mixed layer currents, were reporting from the tropical Pacific. In the eastern Pacific, very strong westward anomalies of 50-60 cm/s were seen on and north of the equator. Climatological January currents in this region are ~60 cm/s toward the west, so these anomalies represented a doubling of the climatological speed. In this region, a number of drifters measured SSTs colder by -0.5 to -3.0 degrees C from typical January values.

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 1993-2010 (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.