scholarly journals Bryozoan faunas at the Tortonian-Messinian transition. A palaeoenvironmental case study from Crete Island, eastern Mediterranean

Geodiversitas ◽  
2021 ◽  
Vol 43 (26) ◽  
Author(s):  
Pierre Moissette ◽  
Assimina Antonarakou ◽  
George Kontakiotis ◽  
Jean-Jacques Cornée ◽  
Vasileios Karakitsios
2010 ◽  
Vol 4 (1) ◽  
pp. 83-88 ◽  
Author(s):  
M. M. Miglietta ◽  
S. Zecchetto ◽  
F. De Biasio

Abstract. In Synthetic Aperture Radar (SAR) imagery, signatures of coherent atmospheric structures, due to sea surface roughness modulation by surface winds, are usually well detected. In the present study, the wind field derived from the Envisat Advanced SAR (ASAR) sensor has been analyzed and compared with those simulated with a regional atmospheric model in a case study over an area located in the eastern Mediterranean Sea, extending southward and eastward of Crete island. This is a region subject to complex wind patterns, due to the interaction of the almost steady northerly Etesian wind with the orography of the islands in the region. The ASAR Wide Swath Mode images provide datasets at resolutions exceptionally high compared to model data, appropriate for investigating the mesoscale phenomena on the marine atmospheric boundary layer and to retrieve the surface wind field. The latter has been obtained with a methodology based on the 2-D Continuous Wavelet Transform, suitable to isolate the backscatter patterns on the base of energy and scale considerations. Numerical simulations with the Weather Research and Forecasting (WRF) model have been performed using three 2-way nested domains, the inner one covering the area of interest with a resolution of 1 km. Several simulations, using different diffusion and boundary layer parameterization schemes, have been performed in a case study corresponding to mountain lee waves detected in the ASAR image. The 10 m winds resulting from the numerical experiments have been compared to those retrieved from the ASAR, both quantitatively and qualitatively, in order to analyze the correspondence of observed and simulated wind structures.


2008 ◽  
Vol 8 (22) ◽  
pp. 6729-6738 ◽  
Author(s):  
N. Kalivitis ◽  
W. Birmili ◽  
M. Stock ◽  
B. Wehner ◽  
A. Massling ◽  
...  

Abstract. Atmospheric particle size distributions were measured on Crete island, Greece in the Eastern Mediterranean during an intensive field campaign between 28 August and 20 October, 2005. Our instrumentation combined a differential mobility particle sizer (DMPS) and an aerodynamic particle sizer (APS) and measured number size distributions in the size range 0.018 μm–10 μm. Four time periods with distinct aerosol characteristics were discriminated, two corresponding to marine and polluted air masses, respectively. In marine air, the sub-μm size distributions showed two particle modes centered at 67 nm and 195 nm having total number concentrations between 900 and 2000 cm−3. In polluted air masses, the size distributions were mainly unimodal with a mode typically centered at 140 nm, with number concentrations varying between 1800 and 2900 cm−3. Super-μm particles showed number concentrations in the range from 0.01 to 2.5 cm−3 without any clear relation to air mass origin. A small number of short-lived particle nucleation events were recorded, where the calculated particle formation rates ranged between 1.1–1.7 cm−3 s−1. However, no particle nucleation and growth events comparable to those typical for the continental boundary layer were observed. Particles concentrations (Diameter <50 nm) were low compared to continental boundary layer conditions with an average concentration of 300 cm−3. The production of sulfuric acid and its subsequently condensation on preexisting particles was examined with the use of a simplistic box model. These calculations suggested that the day-time evolution of the Aitken particle population was governed mainly by coagulation and that particle formation was absent during most days.


2008 ◽  
Vol 8 (2) ◽  
pp. 6571-6601
Author(s):  
N. Kalivitis ◽  
W. Birmili ◽  
M. Stock ◽  
B. Wehner ◽  
A. Massling ◽  
...  

Abstract. Atmospheric particle size distributions were measured on Crete island, Greece in the Eastern Mediterranean during an intensive field campaign between 28 August and 20 October 2005. Our instrumentation combined a differential mobility particle sizer (DMPS) and an aerodynamic particle sizer (APS) and measured number size distributions in the size range 0.018 μm–10 μm. Four time periods with distinct aerosol characteristics were discriminated, two corresponding to marine and polluted air masses, respectively. In marine air, the sub-μm size distributions showed two particle modes centered at 67 nm and 195 nm having total number concentrations between 900 and 2000 cm−3. In polluted air masses, the size distributions were mainly unimodal with a mode typically centered at 140 nm, with number concentrations varying between 1800 and 2900 cm−3. Super-μm particles showed number concentrations in the range from 0.01 to 2.5 cm−3 without any clear relation to air mass origin. A small number of short-lived particle nucleation events were recorded, where the calculated particle formation rates ranged between 1.1–1.7 cm−3 s−1. However, no particle nucleation and growth events comparable to those typical for the continental boundary layer were observed. Particles concentrations (Diameter <50 nm) were low compared to continental boundary layer conditions with an average concentration of 300 cm−3. The production of sulfuric acid and its subsequently condensation on preexisting particles was examined with the use of a simplistic box model. These calculations suggested that the day-time evolution of the Aitken particle population was governed mainly by coagulation and that particle formation was absent during most days.


2020 ◽  
Vol 162 ◽  
pp. 103205 ◽  
Author(s):  
Hung Manh Nguyen ◽  
Ioannis Savva ◽  
Periklis Kleitou ◽  
Demetris Kletou ◽  
Fernando P. Lima ◽  
...  

2019 ◽  
Vol 114 ◽  
pp. 93-117
Author(s):  
Trevor Van Damme

This paper examines Late Bronze Age chipped ceramic and stone discs known most commonly as stoppers. Stoppers are distinguished from other classes of archaeological finds, including pierced discs and lids. Although it has long been known that stoppers could play a role in sealing ceramic vessels, recent scholarship has preferred to see them as multifunctional. For this article, 158 stoppers and 100 spout apertures from transport stirrup jar spouts found in secure Late Bronze Age III contexts have been studied. The results demonstrate a strong correlation in the apertures of transport stirrup jar spouts and the maximum diameter of stoppers that points to a meaningful relationship between the two. As the primary transport container of the Late Bronze Age, transport stirrup jars required careful sealing in order to allow their contents to transit without spilling or spoiling. There were many possible sealing configurations, however, and indeed this paper demonstrates some support for independent Mycenaean and Minoan traditions. A comparison with sealing traditions throughout the eastern Mediterranean reveals that the stopper method of sealing endured or reoccurred for thousands of years for the storage and transport of a specific commodity – wine. I conclude with the case study of stopper distributions at ancient Eleon, Boeotia, in order to show that a contextualised study of stoppers and stoppering activities in domestic structures has much to contribute to the study of social processes and domestic consumption practices.


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