level and the CTD profile at the stations. However, the total transport obtained
using the suggested method does not have to tend to a strictly defined value (in the
case of quasi-zonal sections across the Atlantic, Indian, and Pacific oceans) or to
some range of temporal variability (in the case of quasi-meridional sections in the
Southern Ocean). The same is related to the barotropic and baroclinic components
separately. An illustration of this statement is that quite often the total barotropic
transport over the section exceeds the variability of its instantaneous values. In
Table 2, this corresponds to the range of values ΔQ
′
alt t
ð Þ that do not cross the zero
line. The total transport obtained in this manner is only an approximation to the real
values. The same conclusion is related to the total transport recovered from the
ADT data at stations. To obtain a final estimate of the total transport across the
section or the range of its variability, depending on the restrictions on the total
transport, it is necessary to study the variability of the baroclinic transport component during the section time period based on analysis of the measurements in the
ocean depth.
Conclusions
1. The main error component in the estimates of the barotropic transports over
oceanic sections from the satellite altimetry data is caused by the Formal
Mapping Error.
2. The non-stationarity of the current field in combination with non-simultaneous
measurements at stations of a hydrographic section can lead to significant (i.e.,
exceeding the error in calculating the barotropic transport, based on the Formal
Mapping Error) distortions of the transport estimations over the sections based
on the ADCP measurements of velocity. Thus, the estimates of these
non-stationarity and non-simultaneity are absolutely necessary in the analysis of
the field data in the ocean, both with respect to the calculation of the total
transport across the section, and with respect to the investigation of the structure
of this transport.
3. The account for the deviation of the barotropic transport caused by the
non-stationarity of the current field and non-simultaneity of hydrographic
measurements allows us to add an increment to the total transport, determined
from the instant ADCP measurements over a section, only up to some
approximation of the real total transport. To obtain a final estimate of the total
transport across the hydrographic section, it is necessary to study the variability
of the baroclinic current component on the basis of the analysis of the measurements in the ocean column.
Acknowledgements The work was supported by the Russian Science Foundation, grant
16-17-10149. The author is grateful to E. G. Morozov, and K. V. Lebedev for useful comments
when preparing the text of this contribution.
Influence of the Current Field Non-stationarity …
395
using the suggested method does not have to tend to a strictly defined value (in the
case of quasi-zonal sections across the Atlantic, Indian, and Pacific oceans) or to
some range of temporal variability (in the case of quasi-meridional sections in the
Southern Ocean). The same is related to the barotropic and baroclinic components
separately. An illustration of this statement is that quite often the total barotropic
transport over the section exceeds the variability of its instantaneous values. In
Table 2, this corresponds to the range of values ΔQ
′
alt t
ð Þ that do not cross the zero
line. The total transport obtained in this manner is only an approximation to the real
values. The same conclusion is related to the total transport recovered from the
ADT data at stations. To obtain a final estimate of the total transport across the
section or the range of its variability, depending on the restrictions on the total
transport, it is necessary to study the variability of the baroclinic transport component during the section time period based on analysis of the measurements in the
ocean depth.
Conclusions
1. The main error component in the estimates of the barotropic transports over
oceanic sections from the satellite altimetry data is caused by the Formal
Mapping Error.
2. The non-stationarity of the current field in combination with non-simultaneous
measurements at stations of a hydrographic section can lead to significant (i.e.,
exceeding the error in calculating the barotropic transport, based on the Formal
Mapping Error) distortions of the transport estimations over the sections based
on the ADCP measurements of velocity. Thus, the estimates of these
non-stationarity and non-simultaneity are absolutely necessary in the analysis of
the field data in the ocean, both with respect to the calculation of the total
transport across the section, and with respect to the investigation of the structure
of this transport.
3. The account for the deviation of the barotropic transport caused by the
non-stationarity of the current field and non-simultaneity of hydrographic
measurements allows us to add an increment to the total transport, determined
from the instant ADCP measurements over a section, only up to some
approximation of the real total transport. To obtain a final estimate of the total
transport across the hydrographic section, it is necessary to study the variability
of the baroclinic current component on the basis of the analysis of the measurements in the ocean column.
Acknowledgements The work was supported by the Russian Science Foundation, grant
16-17-10149. The author is grateful to E. G. Morozov, and K. V. Lebedev for useful comments
when preparing the text of this contribution.
Influence of the Current Field Non-stationarity …
395