 |
| Titel |
Spatial and temporal variability of thermohaline properties in the Bay of Koper (northern Adriatic Sea) |
| VerfasserIn |
Rok Soczka Mandac, Dusan Zagar, Jadran Faganeli |
| Konferenz |
EGU General Assembly 2013
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250082590
|
|
|
|
|
|
| Zusammenfassung |
| In this study influence of fresh water discharge on the spatial and temporal variability of
thermohaline (TH) conditions is explored for the Bay of Koper (Bay). The Bay is subject
to different driving agents: wind stress (bora, sirocco), tidal and seiches effect,
buoyancy fluxes, general circulation of the Adriatic Sea and discharge of the Rižana and
Badaševica rivers. These rivers have torrential characteristics that are hard to forecast in
relation to meteorological events (precipitation). Therefore, during episodic events the
spatial and temporal variability of TH properties in the Bay is difficult to determine
[1].
Measurements of temperature, salinity and turbidity were conducted monthly on 35 sampling
points in the period: June 2011 - December 2012. The data were processed and spatial
interpolated with an objective analysis method. Furthermore, empirical orthogonal
function analysis (EOF) [2] was applied to investigate spatial and temporal TH
variations.
Strong horizontal and vertical stratification was observed in the beginning of June 2011 due
to high fresh water discharge of the Rižana (31 m3/s) and Badaševica (2 m3/s) rivers.
The horizontal gradient (ΔT = 6°C) was noticed near the mouth of the Rižana
river. Similar pattern was identified for salinity field on the boundary of the front
where the gradient was ΔS = 20 PSU. Vertical temperature gradient was ΔT =
4°C while salinity gradient was ΔS = 18 PSU in the subsurface layer at depth of 3
m.
Spatial analysis of the first principal component (86% of the total variance) shows
uniform temperature distribution in the surface layer (1m) during the studied period.
Furthermore, temporal variability of temperature shows seasonal variation with a minimum
in February and maximum in August. This confirms that episodic events have a
negligible effect on spatial and temporal variation of temperature in the subsurface
layer.
Further analysis will include application of EOF on the salinity, density and total suspended
matter. Additionally, we will investigate the cross correlations between the above mentioned
parameters with singular value decomposition method.
Reference:
1. Faganeli, J., Planinc, R., Pezdic, J., Smodis, B., Stegnar, P., and Ogorelec, B. 1991. Marine
geology of Gulf of Trieste (northern Adriatic): Geochemical aspects. Marine Geology, 99:
93-108.
2. Glover, M., Jenkins, J., and Doney, S. C. 2011. Modeling methods for marine science.
Cambridge University Press, 571 p. |
|
|
|
|
|
|