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elucidated yet. We must also imply the supersaturation of 3% oxygen observed any
place in the oceans., but also we must consider a lot of other processes: from the
sensibility to temperature of the oxygen solubility it can be observed that a water
heating, water that is in equilibrium with the atmosphere leads to a supersaturation in O;
an other mechanism which must be considered is the mixing.- a mixing of waters at two
different temperatures will also give a supersaturation. The third mechanism which
must be considered as contributing to the supersaturation is bules forming.
One of the known model for bule forming was done by Woolf and Thorpe (1991);
At a wind velocity of 7,5 m⁄s this model gives a supersaturation in oxygen of 0,1 %. The
theory of bule injection is probably the cause of a quart from the observed
supersaturation. The remaining suprasaturation in O may be given by some processes as
are the oxygen production by photosynthesis in the ocean surface layer. The
suprasaturation in O leads at a leak of oxygen to the atmosphere gas flux. Another
mechanism that must be considered is the oxygen leak to the ocean termocline by a
vertical exchange. The oxygen production by photosynthesis will equilibrate the leak
rate by these two mechanisms. We can now estimate the oxygen leak by gas exchange.
We will also include the bule injection for the temperature corrections and it is
obtained:
Φ = - kapă[(1 + ζ +Δe)⋅(CO2)aer – (CO2)apă] (18)
The oxygen concentration in water is suprasaturated by 3 % related to the oxygen
concentration in the air, e.g. (CO2)water = 1,03 (CO2)air , where (CO2)air = 0,241 molm -3 is
the saturation concentration, at the surface global mean temperature of 17,64 0 C and
with a water salinity of 24,78 %. The correction given by the process of bule injection is
of 0,007, at a wind velocity of 7,5 ms -1 .
From the oxygen solubility we can estimate a surface temperature lower with
0,3 0 C, that will give ζ = 0,004. For the gas exchange the coefficient obtained from the
model of Liss and Merlival is given in the table nr.3. By using the mean global
temperature it is obtained for the Schmidt number ScO = 663. This value gives a gas
exchange coefficient of 17,4 cm⁄hour from the model of Wanninkhof, and a value of
10,9 cm ⁄ hour from the model of Liss and Merlival. Converting these values in units of
m⁄hour and substituting all the obtained values the gas exchange flux will be
Φ = - 4,4 la - 7,0 m -2 yard -1 (19)
The oxygen production estimation is superimposed onto the typical estimations for the
oxygen biological production in the surface ocean layer that is of the order of 5 mol m-2
yard-1.
On the basis of the previously made analysis, which combines different
expressions from various model for the oxygen superasaturation with some in situ
obtained empirical data, we could give the conclusion that the superasaturation in O,
globally observed at the ocean surface could be explained by a combination of the
following processes: the bule injection, the effect of a lower temperature of the surface
water, and, the most important mechanism – the production of oxygen by
photosynthesis. The phenomenon of oxygen O2 suprasaturation conducted by the
biological processes and the net oxygen flux to the atmosphere which this implies must
be equilibrated in the subsaturation regions by a net flux of oxygen to the ocean. Other
way the level of O2 should decrease has not been observed yet. A zone where there is
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