Turning now to the observations obtained by the Argo
floats, it appears useful to structure the discussion by distinguishing
a number of possible processes that influence
AAIW variability. The 171 time series can be grouped in five
categories: smooth quasi-diffusive flow, elevated variability,
interannual change in the large-scale salinity field, fronts and
eddies, and multiple salinity minima. Each of these categories
will now be addressed in turn.