Mass accumulation rates, age, sedimentation rate and bulk density at the East Pacific Rise

The rate at which hydrothermal precipitates accumulate, as measured by the accumulation rate of manganese, can be used to identify periods of anomalous hydrothermal activity in the past. From a preliminary study of Sites 597 and 598, four periods prior to 6 Ma of anomalously high hydrothermal activity have been identified: 8.5 to 10.5 Ma, 12 to 16 Ma, 17 to 18 Ma, and 23-to-27 Ma. The 18-Ma anomaly is the largest and is associated with the jump in spreading from the fossil Mendoza Ridge to the East Pacific Rise, whereas the 23-to-27-Ma anomaly is correlated with the birth of the Galapagos Spreading Center and resultant ridge reorganization. The 12-to-16-Ma and 8.5-to-10.5-Ma anomalies are correlated with periods of anomalously high volcanism around the rim of the Pacific Basin and may be related to other periods of ridge reorganization along the East Pacific Rise. There is no apparent correlation between periods of fast spreading at 19°S and periods of high hydrothermal activity. We thus suggest that periods when hydrothermal activity and crustal alteration at mid-ocean ridges are the most pronounced may be periods of large-scale ridge reorganization.

Ingestion rate and egg production of copepods collected in the upper 20m in the eastern Mediterranean Sea in April 2008 during SES_GR2

The ingestion on ciliates and phytoplankton dataset is based on samples taken during October 2008 in Northern Aegean Sea, the area influenced by the Black Sea water outflow. A Lagrangian experiment was established and copepod ingestion was estimated from experiments performed at stations according to the different positions of drifters during the cruise. Copepods for the experiments were obtained with slow non-quantitative tows from the upper 20 m layer of the water column using 200 µm mesh size nets fitted with a large non-filtering cod end. For the grazing experiments we used the following copepod species: Clausocalanus furcatus, and Temoraa stylifera according to the relevant reference (Bamstedt et al. 2000). Copepod clearance rates on ciliates were calculated according to Frost equations (Frost 1972). Ingestion rates were calculated by multiplying clearance rates by the initial standing stocks (Bamstedt et al. 2000). The egg production dataset is based on samples taken during October 2008 in Northern Aegean Sea, the area influenced by the Black Sea water outflow. A Lagrangian experiment was established and copepod egg production was estimated from experiments performed at stations according to the different positions of drifters during the cruise. Egg production rates of the dominant calanoid copepods were determined by incubation of fertilised females (eggs female/day) collected in the 0-20m layer. Copepod egg production was measured for the copepods Clausocalanus furcatus, Temora stylifera. On board experiments for the estimation of copepod egg production were taken place. For the estimation of copepod production (mgC/m**2/day), lengths (copepods and eggs) were converted to body carbon (Hopcroft et al., 1998) and production was estimated from biomass and weight-specific egg production rates, by assuming that those rates are representative for juvenile specific growth rates (Berggreen et al., 1988).

Mean snow accumulation rate, and mean methane sulfonate, chloride and nitrate concentration in snow pits and firn cores of Dronning Maud Land

We quantified postdepositional losses of methane sulfonate (MSA-), nitrate, and chloride at the European Project for Ice Coring in Antarctica (EPICA) drilling site in Dronning Maud Land (DML) (75°S, 0°E). Analyses of four intermediate deep firn cores and 13 snow pits were considered. We found that about 26 ± 13% of the once deposited nitrate and typically 51 ± 20% of MSA- were lost, while for chloride, no significant depletion could be observed in firn older than one year. Assuming a first order exponential decay rate, the characteristic e-folding time for MSA- is 6.4 ± 3 years and 19 ± 6 years for nitrate. It turns out that for nitrate and MSA- the typical mean concentrations representative for the last 100 years were reached after 5.4 and 6.5 years, respectively, indicating that beneath a depth of around 1.2-1.4 m postdepositional losses can be neglected. In the area of investigation, only MSA- concentrations and postdepositional losses showed a distinct dependence on snow accumulation rate. Consequently, MSA- concentrations archived at this site should be significantly dependent on the variability of annual snow accumulation, and we recommend a corresponding correction. With a simple approach, we estimated the partial pressure of the free acids MSA, HNO3, and HCl on the basis of Henry's law assuming that ionic impurities of the bulk ice matrix are localized in a quasi-brine layer (QBL). In contrast to measurements, this approach predicts a nearly complete loss of MSA-, NO3 - , and Cl-.

Ingestion rate and egg production of copepods collected in the Turkish Strait during Bilim 2 cruise in April 2008

The copepod Ingestion on ciliates, phytoplankton and the copepod production dataset is based on samples taken during April 2008 in Dardanelles Straits, Marmara Sea and Bosporus Straits at the third priority stations. These experiments were set up according to DoW of Sesame project. Copepods for the experiments were obtained with slow non-quantitative tows from the upper 50 m layer of the water column using 200 µm mesh size nets fitted with a large non-filtering cod end. For the grazing experiments we used the following copepod species: Centropages typicus and Acartia clausi according to the relevant reference (Bamstedt et al. 2000). Copepod clearance rates on ciliates were calculated according to Frost equations (Frost 1972). Ingestion rates were calculated by multiplying clearance rates by the initial standing stocks (Bamstedt et al. 2000). Egg production rates of the dominant calanoid copepods were determined by incubation of fertilised females (eggs/female/day) collected in the 0-20m layer. Copepod egg production was measured for the copepods Centropages typicus and Acartia clausi. On board experiments for the estimation of copepod egg production were taken place. For the estimation of copepod production (mg/m**2/day), lengths (copepods and eggs) were converted to body carbon (Hopcroft et al., 1998) and production was estimated from biomass and weight-specific egg production rates, by assuming that those rates are representative for juvenile specific growth rates (Berggreen et al., 1988).

(Fig. 3) Sepia officinalis standard metobolic rate and seawater pH (NBS) during experiments, 2008

Ocean acidification and associated changes in seawater carbonate chemistry negatively influence calcification processes and depress metabolism in many calcifying marine invertebrates. We present data on the cephalopod mollusc Sepia officinalis, an invertebrate that is capable of not only maintaining calcification, but also growth rates and metabolism when exposed to elevated partial pressures of carbon dioxide (pCO2). During a 6 wk period, juvenile S. officinalis maintained calcification under ~4000 and ~6000 ppm CO2, and grew at the same rate with the same gross growth efficiency as did control animals. They gained approximately 4% body mass daily and increased the mass of their calcified cuttlebone by over 500%. We conclude that active cephalopods possess a certain level of pre-adaptation to long-term increments in carbon dioxide levels. Our general understanding of the mechanistic processes that limit calcification must improve before we can begin to predict what effects future ocean acidification will have on calcifying marine invertebrates.