1. Franck Touratier & Catherine Goyet Lab. IMAGES Université de Perpignan Via Domitia

2. Inorganic Carbon Chemistry Organic Carbon Biology Greenhouse effect Global warming Stratification Circulation Anthropogenic CO 2 Acidification ? ?

3. 1)Scientific background: Measurements of C T and A T during the WOCE program

5. . EMED-BIOPT Sept/2006. SARHYGOL Feb-Dec/2001. SEMANE Jul/2002. RHOFI Jul/2003. BOUSSOLE/AOPEX Jul-Aug/2004.. Cruises off Alger (ISMAL) 2006. TSS DYFAMED & SOLA... METEOR 51/2 Oct-Nov 2001 (University of Kiel, Germany)

6. 2) Scientific objectives: I.To extend our knowledge on the distribution of the properties of the carbonate system using measurements of C T and A T  pH C ant  O2O2 CTCT ATAT S II. To estimate C ant (TrOCA approach; Touratier et al., 2007) and acidification level (  pH)  local estimation with lowered uncertainties, III. To estimate at the global Mediterranean scale C ant (TrOCA) and acidification using an interpolation procedure from S, , and O 2 (Goyet and Davis, 1997). C T = a + b S + c  + d AOU;A T = f (S)

7. EMED-BIOPT 2006 C T (µmol.kg -1 )A T (µmol.kg -1 ) C ant (µmol.kg -1 )  pH

9. 3) How to reach these objectives:  Samples for A T and C T should be collected from surface to the bottom, but preferentially below the MLD,  In order to estimate C ant and  pH, the O 2 concentration should be measured in the same samples. 4) Specific needs on board:  Space on board to store samples:  number of samples must be first estimated 20 samples/box  each box is 0.072 m 3 Ideal temperature for storage is 4°C but samples may support higher temperatures (5-25°C) for several weeks.  The room for storage should be situated close to the CTD deck  Each sample requires 1.5 litre of seawater and samples must be collected just after those for oxygen analysis to minimize CO 2 exchanges.