Conductivity-temperature-depth profile data from the Western Argentine
Basin collected from 1984 to 1989 are used to quantify the cross-fron
t heat and salt transfers associated with the vertical finestructure a
cross the Brazil-Malvinas Confluence. The fluxes are estimated followi
ng the statistical model Of JOYCE (Journal of Physical Oceanography, 7
, 626-629, 1977). The data indicate that the upper ocean cross-front s
tructure of the large-scale temperature and salinity fields is constan
t. The medium-scale finestructure intensity is quantified by the varia
nce of the vertical temperature and salinity gradients in the 10-100 m
wavelength band. Due to the abundance of intrusions, the upper layer
(0-1000 m) variances increase by a factor of four at distances <20 km
from the front. Heat and salt flux estimates associated with medium-sc
ale mixing in the upper ocean are of the order 10(-2)-degrees-C m s-1
and 10(-3) m s-1 respectively. These fluxes are an order of magnitude
greater than available estimates for other frontal regions. The medium
-scale finestructure may therefore play a key role in the dissipation
of eddies and intrusive lenses in the region. Heat and salt fluxes bet
ween North Atlantic Deep Water and Circumpolar Deep Water are 6.5 x 10
(-4)-degrees-C m s-1 and 1.8 x 10(-4) m s-1, and agree with existing e
stimates. Extrapolation of upper layer Brazil-Malvinas Confluence cros
s-frontal fluxes to the Subtropical Convergence across the South Atlan
tic suggests that the medium-scale southward heat flux is about 20% of
the oceanic northward heat flux at 30-degrees-S. Similarly, the fresh
water flux balances 20% of the excess evaporation north of 30-degrees-
S.