 |
| Titel |
Climatological variations of total alkalinity and total dissolved inorganic carbon in the Mediterranean Sea surface waters |
| VerfasserIn |
E. Gemayel, A. E. R. Hassoun, M. A. Benallal, C. Goyet, P. Rivaro, M. Abboud-Abi Saab, E. Krasakopoulou, F. Touratier, P. Ziveri |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
2190-4979
|
| Digitales Dokument |
URL |
| Erschienen |
In: Earth System Dynamics ; 6, no. 2 ; Nr. 6, no. 2 (2015-12-15), S.789-800 |
| Datensatznummer |
250115491
|
| Publikation (Nr.) |
 copernicus.org/esd-6-789-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| A compilation of data from several cruises between 1998 and 2013 was used to derive
polynomial fits that estimate total alkalinity (AT) and total
dissolved inorganic carbon (CT) from measurements of salinity and
temperature in the Mediterranean Sea surface waters. The optimal equations
were chosen based on the 10-fold cross-validation results and revealed that
second- and third-order polynomials fit the AT and CT
data respectively. The AT surface fit yielded a root mean square
error (RMSE) of ± 10.6 μmol kg−1, and salinity and
temperature contribute to 96 % of the variability. Furthermore, we present
the first annual mean CT parameterization for the Mediterranean
Sea surface waters with a RMSE of ± 14.3 μmol kg−1.
Excluding the marginal seas of the Adriatic and the Aegean, these equations
can be used to estimate AT and CT in case of the lack
of measurements. The identified empirical equations were applied on the
0.25° climatologies of temperature and salinity, available from the
World Ocean Atlas 2013. The 7-year averages (2005–2012) showed that
AT and CT have similar patterns with an increasing
eastward gradient. The variability is influenced by the inflow of cold
Atlantic waters through the Strait of Gibraltar and by the oligotrophic and
thermohaline gradient that characterize the Mediterranean Sea. The
summer–winter seasonality was also mapped and showed different patterns for
AT and CT. During the winter, the AT and
CT concentrations were higher in the western than in the eastern
basin. The opposite was observed in the summer where the eastern basin was
marked by higher AT and CT concentrations than in
winter. The strong evaporation that takes place in this season along with the
ultra-oligotrophy of the eastern basin determines the increase of both
AT and CT concentrations. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|