scholarly journals QUATERNARY SOIL-GEOLOGICAL STRATIGRAPHY IN GREECE

2018 ◽  
Vol 36 (2) ◽  
pp. 856 ◽  
Author(s):  
R. Paepe ◽  
I. Mariolakos ◽  
E. Van Overloop ◽  
S. Nassopoulou ◽  
J. Hus ◽  
...  
Keyword(s):  
Eastern Mediterranean ◽  
Ice Age ◽  
Glacial Cycle ◽  
Last Interglacial ◽  
Middle Term ◽  
Tropical Regions ◽  
The Holocene ◽  
Of Greece

Peloponnesus and Crete are probably offering the best possible standard sections for Eastern Mediterranean Pleistocene Series. Complete Pleistocene Standard Lithostratigraphic Sections from Sparta (Peloponnesus) and Kandanos (Crete) reveal continuous Pleistocene Land Sequences composed of cyclic palaeosol levels interfering with clastic fluvial, eolian (loess) and gravel deposits comparable with analogues found elswhere over the earth. Most suitable for correlation are: a) the standard Idfess area of Northern Europe, Russia and China, and b) the subtropical and tropical regions of Africa and Asia. The standard Greek Pleistocene Lithostratigraphic Sequence independently recorded at both sites (and partially from sites in other regions of Greece) reveal a number of 103 palaeosols of both interglacial and interstadial stages, indicating the extreme warm to relative warm phases of the Pleistocene ice age. This number suits surprisingly well to the 103 levels of the equally warm odd numbered oxygen isotopie stages (OIS) of the Pleistocene deep sea record which equally encompass the warm phases of the Pleistocene. Special attention is given to the Upper Pleistocene of Koroni (Southern Peloponnesus) as a case study for the Last Interglacial - Last Glacial Cycle, i.e. the middle term cycle extending in time from 127 Ka (thousand years) till 10 Ka or beginning of the Holocene. It stands as a model for the recurrent 100 Ka cycles of the long term overall Pleistocene record. Finally, in addition to the Pleistocene, the twenty wet - dry cycles of the Holocene are reviewed.

Palynology of the Last Interglacial-Glacial Cycle in Midlatitudes of Southern Chile

1981 ◽  
Vol 16 (3) ◽  
pp. 293-321 ◽  
Author(s):  
Calvin J. Heusser
Keyword(s):  
Primary Component ◽  
Southern Chile ◽  
Glacial Cycle ◽  
Last Interglacial ◽  
The Holocene ◽  
Westerly Winds ◽  
Pollen And Spores ◽  
Components Analysis ◽  
Age Relations ◽  
Nothofagus Dombeyi

AbstractPollen and spores in stratigraphic sections located between 40 and 42°S range in age from the Holocene, through much of the Llanquihue Glaciation, to the last interglaciation. Chronology of the stratigraphy derives from some 35 14C ages and the age relations of Llanquihue Drift and related deposits. Q-Mode, rotated, principal-components analysis of four key pollen records covering the last interglacial-glacial cycle resulted in four leading components: Nothofagus dombeyi type, Gramineae, Weinmannia-Fitzroya type, and Myrtaceae. Analysis emphasizes interaction between the first two components. Loadings of Gramineae during the interglaciation are high, unlike the Holocene; Weinmannia-Fitzroya-type loadings, prominent in the Holocene, are negligible during the interglaciation. N. dombeyi type is the primary component during Llanquihue Glaciation; it becomes modified by increases of Gramineae sometime after 31,000 and before 14,000 yr B.P. and of Myrtaceae later. The Myrtaceae with Weinmannia-Fitzroya type also registers some activity around 42,000 yr B.P. Fluctuations in the belt of westerly winds, reflecting changing meteorological conditions in polar latitudes, are suggested by these data. With the belt located farther south than it is today, interglacial climate was much drier and warmer than during the Holocene; more northerly displacement of the belt obtained when climate was colder during Llanquihue Glaciation. Evidence from comparable latitudes in the Southern Hemisphere points toward a synchrony of major climatic events indicating harmonious fluctuations in the position of the westerlies.

Climate studies with a coupled atmosphere-upper-ocean-ice-sheet model

1989 ◽  
Vol 329 (1604) ◽  
pp. 249-261 ◽  
Keyword(s):  
Seasonal Cycle ◽  
Low Frequency ◽  
Coupled Model ◽  
Upper Ocean ◽  
Glacial Cycle ◽  
Last Interglacial ◽  
The North ◽  
Technical Report ◽  
Averaged Model

A two-dimensional zonally averaged model has been developed for simulating the seasonal cycle of the climate of the Northern Hemisphere. The atmospheric component of the model is based on the two-level quasi-geostrophic potential vorticity system of equations. At the surface, the model has land—sea resolution and incorporates detailed snow and sea-ice mass budgets. The upper ocean is represented by an integral mixed-layer model that takes into account the meridional advection and turbulent diffusion of heat. Comparisons between the computed present-day climate and climatological data show that the model does reasonably well in simulating the seasonal cycle of the temperature field. In response to a projected CO 2 trend based on the scenario of Wuebbles et al. (DOE/ NBB-0066 Technical Report 15 (1984)), the modelled annual hemispheric mean surface temperature increases by 2 °C between 1983 and 2063. In the high latitudes, the response undergoes significant seasonal variations. The largest surface warmings occur during autumn and spring. The model is then asynchronously coupled to a model that simulates the dynamics of the Greenland, the Eurasian and the North American ice sheets in order to investigate the transient response of the climate to the long-term insolation anomalies caused by orbital perturbations. Over the last interglacial-glacial cycle, the coupled model produces continental ice-volume changes that are in general agreement with the low-frequency part of palaeoclimatic records.

scholarly journals Lower oceanic <i>δ</i><sup>13</sup>C during the last interglacial period compared to the Holocene

2021 ◽  
Vol 17 (1) ◽  
pp. 507-528
Author(s):  
Shannon A. Bengtson ◽  
Laurie C. Menviel ◽  
Katrin J. Meissner ◽  
Lise Missiaen ◽  
Carlye D. Peterson ◽  
...  
Keyword(s):  
North Atlantic ◽  
Interglacial Period ◽  
Oceanic Circulation ◽  
Last Interglacial ◽  
The Holocene ◽  
Last Interglacial Period ◽  
Significant Difference ◽  
Depth Extent ◽  
Global Carbon

Abstract. The last time in Earth's history when high latitudes were warmer than during pre-industrial times was the last interglacial period (LIG, 129–116 ka BP). Since the LIG is the most recent and best documented interglacial, it can provide insights into climate processes in a warmer world. However, some key features of the LIG are not well constrained, notably the oceanic circulation and the global carbon cycle. Here, we use a new database of LIG benthic δ13C to investigate these two aspects. We find that the oceanic mean δ13C was ∼ 0.2 ‰ lower during the LIG (here defined as 125–120 ka BP) when compared to the Holocene (7–2 ka BP). A lower terrestrial carbon content at the LIG than during the Holocene could have led to both lower oceanic δ13C and atmospheric δ13CO2 as observed in paleo-records. However, given the multi-millennial timescale, the lower oceanic δ13C most likely reflects a long-term imbalance between weathering and burial of carbon. The δ13C distribution in the Atlantic Ocean suggests no significant difference in the latitudinal and depth extent of North Atlantic Deep Water (NADW) between the LIG and the Holocene. Furthermore, the data suggest that the multi-millennial mean NADW transport was similar between these two time periods.

scholarly journals THE APPLICATION OF CYCLOSTRATIGRAPHY AND ASTROCHRONOLOGY IN THE NEOGENE MARINE DEPOSITS OF EASTERN MEDITERRANEAN: METOCHIA SECTION (GAVDOS ISLAND)

2006 ◽  
Vol 39 (1) ◽  
pp. 17
Author(s):  
A. Antonarakou ◽  
H. Drinia ◽  
F. Pomoni-Papaioannou
Keyword(s):  
Eastern Mediterranean ◽  
Climatic Changes ◽  
Sea Surface ◽  
Time Interval ◽  
Short Term ◽  
Solar Insolation ◽  
Marine Deposits ◽  
Long Term Trend

Significant lithostratigraphical and micropaleontological signatures, of Milankovitchscale climatic changes are recorded in Miocene deep-sea sediments. As a case study, the Metochia Section, in Gavdos Island, which covers the time interval from 9.7 to 6.6 Ma, is used. This study emphasizes the sedimentological and micropaleontological characteristics of the section, attributed to Milankovitch-scale climatic changes. The short-term variations in climate and faunal composition are related to precession- controlled sedimentary cycles and the long-term trend in climate is related to eccentricity and obliquity cycles. Regional changes in sea surface temperature in combination with variations of solar insolation have caused the cyclical astronomical controlled pattern of Globorotalia species.

scholarly journals Wave Analysis for Offshore Aquaculture Projects: A Case Study for the Eastern Mediterranean Sea

Climate ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 2
Author(s):  
Flora E. Karathanasi ◽  
Takvor H. Soukissian ◽  
Daniel R. Hayes
Keyword(s):  
Mediterranean Sea ◽  
Wave Height ◽  
Significant Wave Height ◽  
Eastern Mediterranean ◽  
Wave Climate ◽  
Eastern Mediterranean Sea ◽  
Significant Wave ◽  
Offshore Aquaculture

The investigation of wave climate is of primary concern for the successful implementation of offshore aquaculture systems as waves can cause significant loads on them. Up until now, site selection and design (or selection) of offshore cage system structures on extended sea areas do not seem to follow any specific guidelines. This paper presents a novel methodology for the identification of favorable sites for offshore aquaculture development in an extended sea area based on two important technical factors: (i) the detailed characterization of the wave climate, and (ii) the water depth. Long-term statistics of the significant wave height, peak wave period, and wave steepness are estimated on an annual and monthly temporal scale, along with variability measures. Extreme value analysis is applied to estimate the design values and associated return periods of the significant wave height; structures should be designed based on this data, to avoid partial or total failure. The Eastern Mediterranean Sea is selected as a case study, and long-term time series of wave spectral parameters from the ERA5 dataset are utilized. Based on the obtained results, the most favorable areas for offshore aquaculture installations have been identified.

scholarly journals Depositional conditions on an alluvial fan at the turn of the Weichselian to the Holocene – a case study in the Żmigród Basin, southwest Poland

Geologos ◽  
2016 ◽  
Vol 22 (2) ◽  
pp. 105-120 ◽  
Author(s):  
Paweł Zieliński ◽  
Robert J. Sokołowski ◽  
Stanisław Fedorowicz ◽  
Barbara Woronko ◽  
Beata Hołub ◽  
...  
Keyword(s):  
Alluvial Fan ◽  
Luminescence Dating ◽  
Braided River ◽  
Gis Analysis ◽  
The Holocene ◽  
Sedimentary Succession ◽  
Late Weichselian ◽  
Stratigraphic Succession

Abstract Presented are the results of research into the fluvio-aeolian sedimentary succession at the site of Postolin in the Żmigród Basin, southwest Poland. Based on lithofacies analysis, textural analysis, Thermoluminescence and Infrared-Optical Stimulated Luminescence dating and GIS analysis, three lithofacies units were recognised and their stratigraphic succession identified: 1) the lower unit was deposited during the Pleni-Weichselian within a sand-bed braided river functioning under permafrost conditions within the central part of the alluvial fan; 2) the middle unit is the result of aeolian deposition and fluvial redeposition on the surface of the fan during long-term permafrost and progressive decrease of humidity of the climate at the turn of the Pleni- to the Late Weichselian; 3) the upper unit accumulated following the development of longitudinal dunes at the turn of the Late Weichselian to the Holocene; the development of dunes was interrupted twice by the form being stabilised by vegetation and soil development.

scholarly journals Lower oceanic 𝛿<sup>13</sup>C during the Last Interglacial compared to the Holocene

2020 ◽  
Author(s):  
Shannon A. Bengtson ◽  
Laurie C. Menviel ◽  
Katrin J. Meissner ◽  
Lise Missiaen ◽  
Carlye D. Peterson ◽  
...  
Keyword(s):  
North Atlantic ◽  
Global Carbon Cycle ◽  
Oceanic Circulation ◽  
Last Interglacial ◽  
The Holocene ◽  
Time Period ◽  
Significant Difference ◽  
Depth Extent ◽  
Global Carbon

Abstract. The last time in Earth’s history when the high latitudes were warmer than during pre-industrial times was the last interglacial (LIG, 129–116 ka BP). Since the LIG is the most recent and best documented warm time period, it can provide insights into climate processes in a warmer world. However, some key features of the LIG are not well constrained, notably the oceanic circulation and the global carbon cycle. Here, we use a new database of LIG benthic 𝛿13C to investigate these two aspects. We find that the oceanic mean 𝛿13C was ~ 0.2 ‰ lower during the LIG (here defined as 125–120 ka BP) when compared to the mid-Holocene (7–4 ka BP). As the LIG was slightly warmer than the Holocene, it is possible that terrestrial carbon was lower, which would have led to both a lower oceanic 𝛿13C and atmospheric 𝛿13CO2 as observed in paleo-records. However, given the multi-millennial timescale, the lower oceanic 𝛿13C most likely reflects a long-term imbalance between weathering and burial of carbon. The 𝛿13C distribution in the Atlantic Ocean suggests no significant difference in the latitudinal and depth extent of North Atlantic Deep Water (NADW) between the LIG and the mid-Holocene. Furthermore, the data suggests that the multi-millennial mean NADW transport was similar between these two time periods.

scholarly journals Marine litter from beach-based sources: Case study of an Eastern Mediterranean coastal town

2018 ◽  
Author(s):  
Michelle E. Portman ◽  
Ruth E Brennan
Keyword(s):  
Eastern Mediterranean ◽  
Institutional Context ◽  
Active Role ◽  
Short Term ◽  
Policy Makers ◽  
Marine Litter ◽  
Management Intervention ◽  
Survey Results

Marine litter has been a serious and growing problem for some decades now. Yet, there is still much speculation among researchers, policy makers and planners about how to tackle marine litter from land-based sources. This paper provides insights into approaches for managing marine litter by reporting and analyzing survey results of litter dispersal and makeup from three areas along an Arab-Israeli coastal town in view of other recent studies conducted around the Mediterranean Sea. Based on our results and analysis, we posit that bathing beach activities should be a high priority for waste managers as a point of intervention and beach-goers must be encouraged to take a more active role in keeping beaches clean. Further, plastic fragments on the beach should be targeted as a first priority for prevention (and cleanup) of marine litter with plastic bottle caps being a high priority to be targeted among plastics. More survey research is needed on non-plastic litter composition for which amounts and geographic dispersal in the region vary greatly from place to place along Mediterranean shores. In general, findings of this study lead us to recommend exploring persuasive beach trash can design coupled with greater enforcement for short term waste management intervention while considering the local socio-economic and institutional context further for long-term efforts.

scholarly journals Climate changes in interior semi-arid Spain from the last interglacial to the late Holocene

2019 ◽  
Author(s):  
Dongyang Wei ◽  
Penélope González-Sampériz ◽  
Graciela Gil-Romera ◽  
Sandy P. Harrison ◽  
I. Colin Prentice
Keyword(s):  
Late Holocene ◽  
Potential Evapotranspiration ◽  
Weighted Averaging ◽  
Glacial Cycle ◽  
Last Interglacial ◽  
Pronounced Increase ◽  
The Holocene ◽  
Western Mediterranean Basin ◽  
Summer Warming ◽  
Temperature Seasonality

Abstract. The El Cañizar de Villarquemado sequence provides a palaeoenvironmental record from the western Mediterranean Basin spanning the interval from the last part of MIS6 to the late Holocene. The pollen and sedimentological records provide qualitative information about changes in temperature seasonality and moisture conditions. We use Weighted Averaging Partial Least-Squares (WA-PLS) regression to derive quantitative reconstructions of winter and summer temperature regimes from the pollen data, expressed in terms of the mean temperature of the coldest month (MTCO) and growing degree days above a baseline of 0 °C (GDD0) respectively. We also reconstruct a moisture index (MI), the ratio of annual precipitation to annual potential evapotranspiration, taking account of the effect of low CO2 on water use efficiency. We find a rapid summer warming at the transition to MIS5. Summers were cold during MIS4 and MIS2, but some intervals in MIS3 were characterized by summers as warm as the warmest phases of MIS5 or the Holocene. However, MIS3 was not significantly warmer in winter than other intervals, and there was a gradual decline in winter temperature from MIS4 through MIS3 to MIS2. The pronounced changes in temperature seasonality during MIS5 and MIS1 are consistent with changes in summer insolation. The ecophysiological effects of changing CO2 concentration through the glacial cycle has a significant impact on reconstructed MI. Conditions became progressively more humid during MIS5 and MIS4 was also relatively humid, while MIS3 was more arid. High MI values are reconstructed during the deglaciation and there was a pronounced increase in aridity during the Holocene. Changes in MI are anti-correlated with changes in GDD0, with increased MI during intervals of summer warming indicating a strong influence of temperature on evapotranspiration. Although our main focus here is on longterm changes in climate, the Villarquemado record also shows millennial-scale changes corresponding to Dansgaard-Oeschger cycles.

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