Upper Ocean Heat and Salt Balances in the Western Equatorial Paci c in Response to the Intraseasonal Oscillation During TOGA COARE
Robert A. Weller
Steven P. Anderson
School of Ocean and Earth Science and Technology
University of Hawaii
Honolulu, HI 96822
Woods Hole Oceanographic Institution
Woods Hole, MA, USA 02543
During the TOGA COARE Intensive Observing Period (IOP) from November 1992
through February 1993, temperature, salinity and velocity profiles
were repeatedly obtained within a 130~km times 130~km region near the center of
the Intensive Flux Array (IFA) in the western equatorial Pacific warm pool.
Together with high quality measurements of air-sea heat flux, rainrate,
upper ocean microstructure, and penetrating solar radiation, they make
up a unique dataset for upper ocean heat and freshwater budget studies.
Three survey cruises sampled different phases of the Intraseasonal Oscillation
(ISO) during the IOP.
Temporal evolution and advective terms in the heat and salt balance
equations, on time scale of three days and longer, are estimated using
the survey data.
The upper ocean (0--50 m) heat and salt budgets at the center of the
IFA were estimated and are closed to within 10wm of observed air-sea heat fluxes and
to within approximately 20% of observed rainrates during each of the
Generally, advection in the upper ocean can not be neglected during the
Zonal advection alternates sign, but had a net warming and freshening
Meridional advection decreased temperature and increased salinity in the
while vertical advection warmed and freshened the surface layer because
of the general downwelling trend.
Heat advection is as important as the net air-sea flux during the westerly
wind burst time periods.
The sub-ISO time scale upper ocean dynamics, such as the strong
meridional advection caused by inertial motions, are found to
have important contributions to the upper ocean heat and freshwater
PDF version of this report.
Last modified: June 7, 2000