Seemingly divergent sea surface temperature proxy records in the central Mediterranean during the last deglacial

Abstract. Sea surface temperatures (SSTs) were reconstructed over the last 25 000 yr using alkenone paleothermometry and planktonic foraminifera assemblages from two cores of the central Mediterranean Sea: the MD04-2797 core (Siculo–Tunisian channel) and the MD90-917 core (South Adriatic Sea). Comparison of the centennial scale structure of the two temperature signals during the last deglacial period reveals significant differences in timing and amplitude. We suggest seasonal changes likely account for seeming proxy record divergences during abrupt transitions from glacial to interglacial climates and for the apparent short duration of the Younger Dryas (YD) depicted by the alkenone time-series, a feature that has already been stressed in earlier studies on the Mediterranean deglaciation.

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Seemingly divergent sea surface temperature proxy records in the central Mediterranean during the last deglaciation

Climate of the Past ◽

10.5194/cp-9-1375-2013 ◽

2013 ◽

Vol 9 (3) ◽

pp. 1375-1383 ◽

Cited By ~ 8

Author(s):

M.-A. Sicre ◽

G. Siani ◽

D. Genty ◽

N. Kallel ◽

L. Essallami

Keyword(s):

Adriatic Sea ◽

Planktonic Foraminifera ◽

Sea Surface ◽

Last Deglaciation ◽

Central Mediterranean ◽

Proxy Record ◽

Proxy Records ◽

The Last Deglaciation ◽

Temperature Proxy ◽

Two Temperature

Abstract. Sea surface temperatures (SSTs) were reconstructed over the last 25 000 yr using alkenone paleothermometry and planktonic foraminifera assemblages from two cores of the central Mediterranean Sea: the MD04-2797 core (Siculo–Tunisian channel) and the MD90-917 core (South Adriatic Sea). Comparison of the centennial scale structure of the two temperature signals during the last deglaciation period reveals significant differences in timing and amplitude. We suggest that seasonal changes likely account for seemingly proxy record divergences during abrupt transitions from glacial to interglacial climates and for the apparent short duration of the Younger Dryas (YD) depicted by the alkenone time series, a feature that has already been stressed in earlier studies on the Mediterranean deglaciation.

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Paleohydrology reconstruction and Holocene climate variability in the South Adriatic Sea

Climate of the Past Discussions ◽

10.5194/cpd-8-4357-2012 ◽

2012 ◽

Vol 8 (5) ◽

pp. 4357-4399 ◽

Cited By ~ 4

Author(s):

G. Siani ◽

M. Magny ◽

M. Paterne ◽

M. Debret ◽

M. Fontugne

Keyword(s):

Climate Variability ◽

Adriatic Sea ◽

Short Interval ◽

Sea Surface ◽

The South ◽

Short Term ◽

Central Mediterranean ◽

Middle Holocene ◽

The North ◽

Holocene Period

Abstract. Holocene paleohydrology reconstruction was derived combining planktic and benthic stable oxygen and carbon isotopes, sea surface temperatures (SSTs) and oxygen isotope composition of seawater (δ18Ow) from a high sedimentation core collected in the south Adriatic sea (SAS). Chronology of core is based on 10 AMS 14C measures on planktic foraminifera and tephra markers. Results reveal two contrasted paleohydrological periods that reflect (i) a marked lowering of δ 18Ow/salinity during the early to middle Holocene (11.5 ka to 6.3 ka), including the two-steps sapropel S1 deposition, followed during the middle to upper Holocene by (ii) a prevailed period of increased salinity and enhanced arid conditions in the south Adriatic basin. Superimposed on these trends, short-term centennial-scale hydrological events punctuated the Holocene period in the SAS. During the Early to Middle Holocene, a short-term SST cooling together with a prominent δ 18Ow/salinity lowering, more pronounced than during the sapropel S1 phase, delineates the sapropel S1 interruption. This short interval, coeval to the 8.2 ka event, is also distinguished by a resumption of deep-water convection in the SAS as indicated by stable isotope reconstruction on benthic forminifera. After 6 ka, centennial-scale δ18Ow and G. bulloides δ13C lowering, mostly centered between 3 to 0.6 ka, reflect short term hydrological changes related to a more intensive Po river runoff. These short-term events, even of lesser amplitude compared to the early to middle Holocene period, may have induced a lowering of sea surface density and consequently reduced and/or inhibited the formation of deep bottom waters in the SAS. Comparison of the emerging centennial to millennial-scale hydrological record with previous climatic records from the central Mediterranean area and north of the Alps revealed possible synchronicities (within the radiocarbon-dating uncertainty) between phases of lower salinity in SAS and periods of wetter climatic conditions around the north-central Adriatic Sea. Finally, wavelet analyses provide new clues about the potential origin of climate variability in the SAS confirming the evidence for a mid-Holocene transition in the Central Mediterranean climate and the dominance of a ~ 1700 yr periodicity after 6 ka that reflects a plausible connection with the North Atlantic climate system.

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Geochemical Tracer in Coral as a Sea Surface Temperature Proxy: Records from Jukung Coral

ITB Journal of Engineering Science ◽

10.5614/itbj.eng.sci.2010.42.1.5 ◽

2010 ◽

Vol 42 (1) ◽

pp. 65-72 ◽

Cited By ~ 1

Author(s):

S. Y. Cahyarini ◽

J. Zinke

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Sea Surface ◽

Proxy Records ◽

Geochemical Tracer ◽

Temperature Proxy

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Evidence of multidecadal climate variability and the Atlantic Multidecadal Oscillation from a Gulf of Mexico sea-surface temperature-proxy record

Geo-Marine Letters ◽

10.1007/s00367-009-0154-6 ◽

2009 ◽

Vol 29 (6) ◽

pp. 477-484 ◽

Cited By ~ 22

Author(s):

Richard Z. Poore ◽

Kristine L. DeLong ◽

Julie N. Richey ◽

Terrence M. Quinn

Keyword(s):

Climate Variability ◽

Gulf Of Mexico ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Atlantic Multidecadal Oscillation ◽

Sea Surface ◽

Proxy Record ◽

Multidecadal Climate Variability ◽

Temperature Proxy

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Latitudinal Differentiation among Modern Planktonic Foraminiferal Populations of Central Mediterranean: Species–Specific Distribution Patterns and Size Variability

Journal of Marine Science and Engineering ◽

10.3390/jmse9050551 ◽

2021 ◽

Vol 9 (5) ◽

pp. 551

Author(s):

George Kontakiotis ◽

Eirini Efstathiou ◽

Stergios D. Zarkogiannis ◽

Evangelia Besiou ◽

Assimina Antonarakou

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Planktonic Foraminifera ◽

Sea Surface ◽

Distributional Pattern ◽

Central Mediterranean ◽

Specific Distribution ◽

Size Variability ◽

The Mediterranean ◽

Species Specific

Studies of the spatial distribution and size of modern planktonic foraminifera are still lacking in the Mediterranean Sea. In this study, 17 core-top sediments collected from a north-south transect along the central Mediterranean have been analyzed for planktonic foraminiferal content, in terms of their distributional pattern and intraspecific size variability. Among the analyzed planktonic foraminiferal species, Globigerina bulloides and Globigerinoides ruber (w) were the most abundant, presenting an antagonistic behavior and an overall decreasing trend in their average size values from Adriatic to Ionian sub-basins. Intraspecific differences have been also documented for G. ruber (w), with the dominant sensu stricto morphotype to present generally higher frequencies and more constant shell sizes than sensu lato. The greater size variability of the latter is possibly related to its adaptation in particular hydrographic conditions based on its depth habitat preference and ecological characteristics to reach the (sub)optimum growth conditions. The rest of the species occur in minor percentages and show on average 11% increase with decreasing latitude characterized by distinct species-specific size variations along the transect. Our results show that the relationship between planktonic foraminifera shell size and abundance or sea surface temperature are either absent or weaker than previously reported for other regions and that in central Mediterranean assemblages’ size may be mainly related to nutrient availability. Besides the environmental parameters (sea surface temperature, primary productivity, water depth, stratification), the possible hidden cryptic diversity, still lingers to be consistently determined, could give a better understanding of the geographic and morphological differentiation within the Mediterranean planktonic populations.

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Sea Surface Temperatures and Paleoenvironmental Variability in the Central Mediterranean During Historical Times Reconstructed Using Planktonic Foraminifera

Paleoceanography and Paleoclimatology ◽

10.1029/2018pa003529 ◽

2019 ◽

Vol 34 (3) ◽

pp. 394-408 ◽

Cited By ~ 4

Author(s):

Alessandro Incarbona ◽

Lukas Jonkers ◽

Serena Ferraro ◽

Rodolfo Sprovieri ◽

Giorgio Tranchida

Keyword(s):

Planktonic Foraminifera ◽

Sea Surface ◽

Sea Surface Temperatures ◽

Central Mediterranean ◽

Surface Temperatures ◽

Historical Times

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Paleohydrology reconstruction and Holocene climate variability in the South Adriatic Sea

Climate of the Past ◽

10.5194/cp-9-499-2013 ◽

2013 ◽

Vol 9 (1) ◽

pp. 499-515 ◽

Cited By ~ 44

Author(s):

G. Siani ◽

M. Magny ◽

M. Paterne ◽

M. Debret ◽

M. Fontugne

Keyword(s):

Climate Variability ◽

Adriatic Sea ◽

Isotope Composition ◽

Climatic Conditions ◽

Sea Surface ◽

The South ◽

Short Term ◽

Central Mediterranean ◽

The North ◽

Holocene Period

Abstract. Holocene paleohydrology reconstruction is derived combining planktonic and benthic stable oxygen and carbon isotopes, sea surface temperatures (SSTs) and oxygen isotope composition of seawater (δ18Ow) from a high sedimentation core collected in the South Adriatic Sea (SAS). Core chronology is based on 10 AMS 14C measures on planktonic foraminifera and tephra layers. Results reveal two contrasted paleohydrological periods that reflect (i) a marked lowering of δ18Ow/salinity during the early to mid-Holocene (11.5 ka to 6.3 ka), including the two-step sapropel S1 deposition, followed during the mid- to upper Holocene by (ii) a prevailing period of increased salinity and enhanced arid conditions in the South Adriatic Basin. Superimposed on these trends, short-term centennial-scale hydrological events punctuated the Holocene period in the SAS. During the early to mid-Holocene, two main SST coolings together with prominent δ18Ow/salinity lowering delineate the sapropel S1 interruption and the post-sapropel phase between 7.3 to 6.3 ka. After 6 ka, centennial-scale δ18Ow and G. bulloides δ13C lowering, mostly centered between 3 to 0.6 ka, reflect short-term hydrological changes related to more intensive runoff of the Po and/or Apennine rivers. These short-term events, even of lesser amplitude compared to the early to mid-Holocene period, may have induced a lowering of sea surface density and consequently reduced and/or inhibited the formation of deep bottom waters in the SAS. Comparison of the emerging centennial- to millennial-scale hydrological record with previous climatic records from the central Mediterranean area and north of the Alps reveal possible synchronicities (within the radiocarbon-dating uncertainty) between phases of lower salinity in the SAS and periods of wetter climatic conditions around the north-central Adriatic Sea. Finally, wavelet analyses provide new clues about the potential origin of climate variability in the SAS, confirming the evidence for a mid-Holocene transition in the central Mediterranean climate and the dominance of a ~1670-yr periodicity after 6 ka, reflecting a plausible connection with the North Atlantic climate system.

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Deep-Water Cartilaginous Fishes in the Central Mediterranean Sea: Comparison between Geographic Areas with Two Low Impact Tools for Sampling

Journal of Marine Science and Engineering ◽

10.3390/jmse9070686 ◽

2021 ◽

Vol 9 (7) ◽

pp. 686

Author(s):

Angela Carluccio ◽

Francesca Capezzuto ◽

Porzia Maiorano ◽

Letizia Sion ◽

Gianfranco D’Onghia

Keyword(s):

Adriatic Sea ◽

Fish Habitat ◽

Conservation Status ◽

Abundant Species ◽

Cartilaginous Fish ◽

Fish Diversity ◽

Ionian Sea ◽

Central Mediterranean ◽

The North ◽

North Western

Baited lander represents a low impact technique, an alternative to the traditional trawl sampling for collecting data on fish diversity and abundance, especially for threatened species such as Chondrichthyes living in sensitive habitats. In this study, distribution and abundance of cartilaginous fish were compared between two geographic areas, the southern Adriatic Sea and the north-western Ionian Sea, with two low impact sampling gears, an experimental bottom longline and a baited lander. Species diversity was evaluated by applying ecological indices and difference in mean abundances were tested using multivariate analysis. A total of 13 species of cartilaginous fish were collected. Significant differences in the assemblage recorded in the same area using different sampling tools were detected and no significant differences were detected among different areas explored with the same method. Using longline, the most abundant species collected in both areas was Galeus melastomus, while using lander, the most observed species were Dalatias licha in the southern Adriatic Sea and Hexanchus griseus in the north-western Ionian Sea. According to IUCN classification, of the 13 species collected, 2 are near threatened and 5 are threatened. A better governance of sensitive habitats coinciding with the essential fish habitat for these species would ensure them a better conservation status.

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