Search results for "Interglacial"
showing 10 items of 77 documents
Variability in the vertical structure of the water column and paleoproductivity reconstruction in the central-western Mediterranean during the Late P…
2008
Abstract A sedimentary sequence spanning Marine Isotope Stage (MIS) 6 to MIS 2 in core LC07, recovered in the central Mediterranean, has been investigated in order to produce a high-resolution paleoceanographic reconstruction. The changes in productivity deduced from calcareous plankton relative abundances and independently confirmed by the Ba XS fluctuations are linked to the stability of the water column which is mainly controlled by the water mass temperature. During glacial intervals, productivity was generally enhanced. Oligotrophic and warmer water masses with a deepened seasonal thermocline can be inferred for most of MIS5. The magnetic properties of the sediment show increased occur…
21. Abrupt change of El Niño activity off Peru during stage MIS 5e-d
2007
Abstract High-resolution proxy data for El Nino variability during the last glacial cycle were derived from a laminated marine sediment core from a region whose climatology and oceanography is strongly affected by ENSO variability. The proxies used are the seasurface temperature and the lithic flux from the continent onto the continental shelf that is largely controlled by the river flood discharge after strong El Nino rainfall in northern and northern central Peru. The focus of this paper is on an abrupt, possibly orbitally driven change of El Nino activity within marine isotope stage 5e. A similar sharp decline of El Nino activity is also observed during the middle of the Holocene intergl…
Risk and resilience in the late glacial: A case study from the western Mediterranean
2018
Abstract The period spanning the Last Glacial Maximum through early Holocene encompasses dramatic and rapid environmental changes that offered both increased risk and new opportunities to human populations of the Mediterranean zone. The regional effects of global climate change varied spatially with latitude, topography, and distance from a shifting coastline; and human adaptations to these changes played out at these regional scales. To better understand the spatial and temporal dynamics of climate change and human social-ecological-technological systems (or SETS) during the transition from full glacial to interglacial, we carried out a meta-analysis of archaeological and paleoenvironmenta…
African monsoon variability during the previous interglacial maximum.
2002
Little is known about centennial- to millennial-scale climate variability during interglacial times, other than the Holocene. We here present high-resolution evidence from anoxic (unbioturbated) sediments in the eastern Mediterranean Sea that demonstrates a sustained V800-yr climate disturbance in the monsoonal latitudes during the Eemian interglacial maximum (V125 ka BP). Results imply that before and after this event, the Intertropical Convergence Zone (ITCZ) penetrated sufficiently beyond the central Saharan watershed (V21n) during the summer monsoon to fuel flooding into the Mediterranean along the wider North African margin, through fossil river/wadi systems that to date have been cons…
5. Introduction — palaeoclimate reconstructions and dating
2007
Publisher Summary This chapter describes four interglacials preceding the Holocene—that is, during the time from about 100 to 450 kyr. The first knowledge on this time has been extracted almost 40 years ago from marine deep sea cores with a sampling resolution of several thousand of years. Deep ocean sediments can be easily dated, because δ18O stratigraphy can be applied all over the ocean basins and tuned directly to the ice volume/sea-level master curve of SPECMAP, which is based on the beat of the orbital insolation cyclicities. This dynamic climate evolution of the past interglacial must have been of high importance also for the evolution of mankind. Neanderthal hominids lived and hunte…
Mediterranean Coastal Lagoons
2018
On the eastern coast of the Iberian Peninsula—between the Ebro Delta and Cape Palos—the conditions during the Pleistocene, and especially after the Flandrian transgression, favoured the development of beach barrier systems and lagoons along large segments of the coast. The very small tidal range made connections between the sea and lagoons difficult, and this favoured sedimentation processes, which was often accelerated by human activity. Three very different sectors have been differentiated: the Gulf of Valencia, where the largest number of lagoons is found; the cliffed Betic structural sector between Cape Sant Antoni and Cape de les Hortes, in which there are just a few very small lagoons…
The Grotta Grande of Scario (Salerno, Italy): Archaeology and environment during the last interglacial (MIS 5) of the Mediterranean region
2011
Abstract Archeological and paleo-environmental researches carried on the Grotta Grande site illustrate the importance of a multidisciplinary approach among archeologists, palynologists and paleontologists. The archaeology, fauna, pollen and micro-charcoal recovered in two short sedimentary successions (trenches A, F) located close to the entrance of the cave are discussed. The cave opens directly on the Tyrrhenian Sea, 2 km from Scario (Salerno, Campania, Southern Italy). The morphology of the cave and sedimentary processes were controlled by eustatic fluctuations during the late Middle Pleistocene and the early Late Pleistocene. The sea repeatedly occupied the cave. The cave was frequented…
Surface and deep water conditions in the Sicily channel (central Mediterranean) at the time of sapropel S5 deposition
2011
New centennial-scale data of benthic foraminifera assemblages and of stable isotopes of foraminifera shells from the Sicily Channel, representative of surface and bottom waters, over the interval between about 140 and 110 kyr BP, are presented. During this period anoxia developed on the eastern Mediterranean basin and sapropel S5 deposited. Although anoxic sediments have not been deposited in the Sicily Channel, this area is strategic to study the character of intermediate waters, whose chemical-physical properties strongly precondition the eastern Mediterranean deep water formation. So far, no data from these water masses have been obtained, apart from the isotopic composition of shells of…
Biochronological and paleoenvironmental interest of foraminifera lived in restricted environments: application to the study of the western Mediterran…
2002
As a consequence ofthe Flandrian transgression, numerous littoral lakes were f since roughly 6000 BP in the western Mediterranean coast. This kind of environment is colonized, among other groups, by specialized forms of foraminifera. Some species arose in the Upper Tertiary, some others in the Pleistocene and others are exclusively Holocene. Two kinds ofenvironment are proposed in the colonization: one with very low salinity waters where agglutinated test species prevail and another one with brackish waters, dominated by calcareous test species. In addition, Trichohyalus aguayoi can be considered as an acmezone within the Holocene. We propose a cenozone formed by the following assemblage: A…
Surviving the Holocene: Human Ecological Responses to the Current Interglacial in Southern Valencia, Spain
2009
For hunter-gatherer groups, the dramatic changes in climate at the end of the last glacial cycle necessitated rearrangement of land use, including shifts in mobility strategies, settlement location, and resource use. We examine these behavioral changes using lithic attribute data as well as spatial distributions of artifacts and features. Using data from intensive survey and excavation, we trace human ecological response through the onset of the current interglacial in central Mediterranean Spain, comparatively far from the margins of the north-temperate ice sheets.