Chapter I Intro & Objectives - SPREP

PHOENIX ISLANDS PROTECTED AREA MANAGEMENT PLAN
Chapter III. Background, 1. Physical Setting of the Islands
Draft 1 March 2007
In the 1980s, four German cruises (Midpac 1 to IV) were undertaken in the Pacific (Line
Islands, Gilbert Islands, Phoenix Islands, and Marshall Islands) (Glasby 2002).
The Phoenix Islands were oriented along the equator and was predominantly influenced by
the westward-flowing Equatorial Current (northern equatorial branch of the South Equatorial
Current (BEN) and south equatorial branch of the South Equatorial Current (BES)) (Tuna and
Billfish Assessment Program 1993). The Phoenix Islands were subject to the El Niño
Southern Oscillation (ENSO) that occurs every two to seven years and lasts for 18 to 24
months. During ENSO events, the westward tradewinds were reduced and variations and
even reversal of the main currents. This deepens the eastern Pacific thermocline.
The Tuna and Billfish Assessment Programme (1993) provided diagrams of the seasonal
changes in major equatorial surface currents around the Phoenix Islands. These are provided
in Figures III-1.11 to III-1.18 below.
Figure III-1.11. Major currents around the Phoenix Islands in MARCH
Including below the surface temperature and current profiles.
(source: Tuna and Billfish Assessment Programme 1993).
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