Hydrology of the Northern Adriatic
33
a
43 44 45
~ ;2;.5 .-. ~-- ~ --first group
second group
transectD
tbinJ group
o 10 20 30 40 50 60 70 80
distance (lou)
b
36 37 38 39 40
41 42 43 44 45
, \
, ,
::
C!; ~ :
•
' .
I
•
I
I
I
\ . ,
I
I
:,/' J O ;g!
o ~ . , ~ ' I
.-I ·~
~ : :::
first group
I I
.
j t l
I
I
\ I
.
~ J I
>6
.
t .
I
second group
transectD
third group
o 10 20 30 40 50 60 70 80
rustance (Ion)
Fig. 9a.b. a Steady; b residual across section current field at transect D. Positive values indicate southward flow, while negative
ones mean northward flow. Water masses individuated by the cluster analysis are superimposed
with the horizontal and vertical distributions of
the thermohaline parameters. Keeping this in
mind and looking at the three transects analysed
(C, D and E) in more detail, the characteristics of
the hydrological and current fields can be related.
The two cores of water of fluvial origin present at
transect C (indicated by the first group in the
cluster analysis) are evident in both the horizontal and vertical density fields, and may have a
unique origin, the Po river. A series of pulses in
the Po river discharge, during the first part of
September may be the origin of a core of fresh
water) observed as two structures split by the
northward flow in Figs. 8b,9b and lob. The two
mesoscale structures present a different behaviour: the fust one tends to flow southward along
the Italian coast, and it is seen at the south-western part of the basin; the second one seems to
join the anticyclonic gyre positioned along transect C, seen partially at transect D (small core of
first group water and southward residual flow),
and absent at transect E. Between these two
structures, there is a doming of the isopycnals in
correspondence to station 28, which is the centre
of a cyclonic gyre in the residual field pattern.
The same thing happens at section E around station 53, where a core of high density water is present; the residual field, as expected, presents a
strong (30 cm/s) northward current east of this
station, which decreases west of it, but does not
reverse the sign. This is probably due to the fact
that the horizontal gradient on the west side of
33
a
43 44 45
~ ;2;.5 .-. ~-- ~ --first group
second group
transectD
tbinJ group
o 10 20 30 40 50 60 70 80
distance (lou)
b
36 37 38 39 40
41 42 43 44 45
, \
, ,
::
C!; ~ :
•
' .
I
•
I
I
I
\ . ,
I
I
:,/' J O ;g!
o ~ . , ~ ' I
.-I ·~
~ : :::
first group
I I
.
j t l
I
I
\ I
.
~ J I
>6
.
t .
I
second group
transectD
third group
o 10 20 30 40 50 60 70 80
rustance (Ion)
Fig. 9a.b. a Steady; b residual across section current field at transect D. Positive values indicate southward flow, while negative
ones mean northward flow. Water masses individuated by the cluster analysis are superimposed
with the horizontal and vertical distributions of
the thermohaline parameters. Keeping this in
mind and looking at the three transects analysed
(C, D and E) in more detail, the characteristics of
the hydrological and current fields can be related.
The two cores of water of fluvial origin present at
transect C (indicated by the first group in the
cluster analysis) are evident in both the horizontal and vertical density fields, and may have a
unique origin, the Po river. A series of pulses in
the Po river discharge, during the first part of
September may be the origin of a core of fresh
water) observed as two structures split by the
northward flow in Figs. 8b,9b and lob. The two
mesoscale structures present a different behaviour: the fust one tends to flow southward along
the Italian coast, and it is seen at the south-western part of the basin; the second one seems to
join the anticyclonic gyre positioned along transect C, seen partially at transect D (small core of
first group water and southward residual flow),
and absent at transect E. Between these two
structures, there is a doming of the isopycnals in
correspondence to station 28, which is the centre
of a cyclonic gyre in the residual field pattern.
The same thing happens at section E around station 53, where a core of high density water is present; the residual field, as expected, presents a
strong (30 cm/s) northward current east of this
station, which decreases west of it, but does not
reverse the sign. This is probably due to the fact
that the horizontal gradient on the west side of