Climate reconstructions and monitoring in the Mediterranean Sea: A review on some recently discovered high-resolution marine archives

Abstract

Palaeoclimate records are important tools for understanding climate modifications and contextualizing recent anthropogenic perturbations in climate change relative to natural variability in the Earthclimate system. \ud Moreover, time-series proxy records of the main physical and chemical parameters in marine and continental environments are increasingly used for testing climate models in order to ascertain the reliability of projections for future scenarios in our greenhouse modified Earth. \ud In order to account for the limited number of continuous instrumental measurements of climatic variables in the past, such as sea surface temperature (SST), salinity (SSS), sea-level fluctuations and water chemistry, a complementary approach is the examination of geochemical tracers (i. e. trace elements and stable isotopes) in well-dated natural marine archives. \ud \ud Recently, the Mediterranean Sea has been the focus of a number of studies where new high resolution climate archives have been investigated utilizing proxies for sea surface temperature, salinity, marine chemistry, and ocean circulation, different to those available for tropical regions. In particular, vermetids (Dendropoma petraeum), non-tropical zooxanthellate corals (Cladocora caespitosa) and cold-water corals (Desmophyllum dianthus, Lophelia pertusa and Madrepora oculata) have been studied by conventional and advanced analytical techniques (e. g., laser ablation ICP-MS, MC-ICP-MS, synchrotron X-ray fluorescence) and have been successfully used as high-resolution palaeoenvironmental proxies. Vermetid reefs have the potential to yield valuable information on past sea-level changes and SST, through the combination of stable isotopes and radiocarbon dating. The trace element concentration, in combination with U-series and radiocarbon dating, of the skeletal aragonite of the Mediterranean zooxanthellate coral Cladocora caespitosa, and of the coldwater corals Desmophyllum dianthus and Lophelia pertusa, has been successfully demonstrated to be a valid high-resolution SST archive, and a seawater chemistry and ocean circulation proxy, respectively. Here we present a review of our research over the last few years, aiming for the establishment of new natural marine archives collected from various sites of the Mediterranean Sea, reporting on our methodological approaches and main results

Kinetic and Metabolic Isotope Effects in Zooxanthellate and Non-zooxanthellate Mediterranean Corals Along a Wide Latitudinal Gradient

“…Such environmental differences must be cautiously taken into account when investigating and interpreting the skeletal isotope signal of temperate corals. Stable isotope and trace element composition, in combination with U-series and radiocarbon dating of the zooxanthellate coral Cladocora caespitosa, and of the cold-water corals Desmophyllum dianthus, Lophelia pertusa, and Madrepora oculata have been validated as high-resolution paleoenvironmental proxies (Peirano et al, 2004;Silenzi et al, 2005;Cohen et al, 2006;Montagna et al, 2008;López Correa et al, 2010;Trotter et al, 2011).…”

The bivalve Glycymeris pilosa as a multidecadal environmental archive for the Adriatic and Mediterranean Seas

“…Yet there have been very few sclerochronological studies in the Mediterranean despite a number of possible marine archives including vermetid gastropods (Dendropoma petraeum), non-tropical zooxanthellate corals (Cladocora caespitosa) and coldwater corals (Desmophyllum dianthus, Lophelia pertusa and Madrepora oculata) (Montagna et al, 2008). In perhaps the only Mediterranean example from corals, Peirano et al (2009) constructed a multidecadal growth chronology from a living Cladocora caespitosa.…”

A High-Resolution Coral-Based Δ14C Record of Surface Water Processes in the Western Mediterranean Sea

“…However, currently, only sparse 14 C data are available for the Mediterranean Sea and those are derived from mol-lusk shells with a limited age range (Siani et al 2000;Reimer and McCormac 2002). Recent studies have revealed that the shallow-water zooxanthellate Mediterranean coral Cladocora caespitosa can serve as a reliable archive for seawater temperature and pH reconstructions (Peirano et al 2004;Silenzi et al 2005;Montagna et al 2007Montagna et al , 2008Trotter et al 2011) and thus is a potentially useful archive for 14 C studies.…”