The greatest differences are found in the North Pacific and the
North Atlantic and, to a lesser extent, in the Southern Ocean.
Non-negligible differences also are observed in the subtropical
gyres of the South Pacific and South Indian Oceans. In
the (Sub)tropics, Millero et al. [1998a] forced the single
equation to two different intercepts for SST at 20C; one for
the northern and southern (Sub)tropical Pacific and another
for the rest of (Sub)tropics. However, our analysis indicates
that, regardless of basins, only a single intercept of the AT
equation is needed at SSS = 35 and SST = 20C for the entire
(Sub)tropics.