RECENT CHANGES IN THE VENTILATION OF THE MEDITERRANEAN SEA CONSTRAINED BY CFCS, SF6, TRITIUM AND HE-3 DATA.
The Mediterranean Sea has two separate deep convective cells, one in the eastern and one in the western Mediterranean Sea, both of which has experienced significant changes in their deep water formation during the last few decades. Here we present a time series of transient tracer measurements between 1987 and 2011; the data sets consist of different combinations of CFC’s, helium isotopes, tritium and SF6 and are used to quantify ventilation and identify its temporal variability. We also use the relation between the SF6 ages in 2011 and the CFC-12 ages in 1997 of the same oceanic region, which give additional insights to changes in circulation. The comprehensive data set of a cruise in 2011 allowed for empirical constraining the Inverse Gaussian (IG) – Transit Time Distribution (TTD) model with either one (1IG) or two (2IG) main water masses, or transit time distributions. The comparison of ages calculated from transient tracers over the period of 25 years reflects changes in circulation such as the Eastern Mediterranean Transient (EMT) and the West Mediterranean Transition (WMT) and also more recent changes in ventilation.
Tanhua, T., GEOMAR, Germany, firstname.lastname@example.org
Stöven, T., GEOMAR, Germany, email@example.com
Schneider, A., GEOMAR, Germany, firstname.lastname@example.org
Roether, W., University Bremen, Germany, email@example.com
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall
Presentation is given by student: No