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This paper introduces the aims and scope of the RESET project ( RES ponse of humans to abrupt E nvironmental T ransitions), a programme of research funded by the Natural Environment Research Council (UK) between 2008 and 2013; it also provides the context and rationale for papers included in a special volume of Quaternary Science Reviews that report some of the project's findings. RESET examined the chronological and correlation methods employed to establish causal links between the timing of abrupt environmental transitions (AETs) on the one hand, and of human dispersal and development on the other, with a focus on the Middle and Upper Palaeolithic periods. The period of interest is the Last Glacial cycle and the early Holocene (c. 100–8 ka), during which time a number of pronounced AETs occurred. A long-running topic of debate is the degree to which human history in Europe and the Mediterranean region during the Palaeolithic was shaped by these AETs, but this has proved difficult to assess because of poor dating control. In an attempt to move the science forward, RESET examined the potential that tephra isochrons, and in particular non-visible ash layers (cryptotephras), might offer for synchronising palaeo-records with a greater degree of finesse. New tephrostratigraphical data generated by the project augment previously-established tephra frameworks for the region, and underpin a more evolved tephra ‘lattice’ that links palaeo-records between Greenland, the European mainland, sub-marine sequences in the Mediterranean and North Africa. The paper also outlines the significance of other contributions to this special volume: collectively, these illustrate how the lattice was constructed, how it links with cognate tephra research in Europe and elsewhere, and how the evidence of tephra isochrons is beginning to challenge long-held views about the impacts of environmental change on humans during the Palaeolithic. [ABSTRACT FROM AUTHOR]

Aim To explore the magnitude and spatial patterns of last glacial stage orbitally forced climatic changes and suborbital climatic fluctuations in southern Africa, and to evaluate their potential roles in determining present biodiversity patterns. Location Africa south of 15° S. Methods Palaeoclimate scenarios for southern Africa were derived for 17 time slices using outputs from HadCM3 atmosphere-ocean general circulation model experiments, including five designed to mimic Heinrich events. Species distribution models for birds of Karoo (45) or Fynbos (31) were used to simulate species' potential past distributions. Species-richness patterns were assessed for each time slice, and minimum species richness for regional endemics of each biome determined for each grid cell. Areas of greatest 'stability' for endemics of each biome were identified using grid cells with greatest minimum richness. Results Simulated suborbital climatic fluctuations were of greater magnitude than orbitally forced changes and had anomalies of opposite sign in many areas. The principal local drivers of suborbital fluctuations were marked contrasts in South Atlantic circulation and temperature between experiments mimicking Heinrich events and those with only slow forcings. These contrasts in ocean circulation and temperature were consistent with marine sediment core evidence of changes in the South Atlantic coincident with Heinrich events in the North Atlantic. Whereas orbitally forced last glacial climates generally resulted in range expansions and increased species richness in many grid cells compared with the present, the contrasting conditions of Heinrich events resulted in much reduced ranges and species richness, especially for Karoo species. Very few grid cells remained suitable for larger numbers of endemic species of either biome under all palaeoclimate scenarios examined, but this minority of 'stable' grid cells correspond to present diversity centres. Main conclusions Suborbital climatic fluctuations during the last glacial stage were probably of considerable magnitude in southern Africa. This may account for apparent inconsistencies between regional palaeoclimate records, as well as being key to determining present biodiversity patterns. [ABSTRACT FROM AUTHOR]

Abstract: Electron spin resonance (ESR) and 230Th/234U ages of speleothem samples collected from karstic caves located around 3000m elevation in the Aladağlar Mountain Range (AMR), south-central Turkey, were determined in order to provide new insight and information regarding late Pleistocene climate. ESR ages were validated with the 230Th/234U ages of test samples. The ESR ages of 21 different layers of six speleothem samples were found to range mostly between about 59 and 4ka, which cover the Marine Oxygen Isotope Stages (MIS) MIS 3 to MIS 1. Among all, only six layers appear to have deposited during MIS 8 and 5. Most of the samples dated were deposited during the late glacial stage (MIS 2). It appears that a cooler climate with a perennial and steady recharge was more conducive to speleothem development rather than a warmer climate with seasonal recharge in the AMR during the late Quaternary. This argument supports previous findings that suggest a two -fold increase in last glacial maximum mean precipitation in Turkey with respect to the present value. [Copyright &y& Elsevier]

By comparison with the Northern Hemisphere, there is a paucity of high-resolution, continuous records extending into the Last Glacial Maximum from the Southern Hemisphere. With specific reference to coastal eastern Australia, there are long records of paleoclimatic and paleoenvironmental variability available from the tropical north and temperate south. However, there are significant spatial gaps between such records: in particular, until relatively recently, little attention had been paid to the subtropics. This review paper summarises understanding of regional paleoenvironmental and paleoclimatic variability in coastal eastern Australia during the termination of the Last Glacial Stage, with the aim of highlighting gaps in the current state of knowledge. Recommendations for future research are prioritised to answer knowledge gaps in understanding climate variability in eastern Australia between ca 33-18 kyr BP. [ABSTRACT FROM AUTHOR]

Three extensive buried forests of the Late Quaternary were unearthed at Ooyazawa, Aomori, in the northern part of Honshu Island of Japan during construction of a flood water reservoir. The lower and middle buried forests were formed by activities of the Towada Volcano and dated from the early period of the Last Glacial Maximum and the Late Glacial Period, respectively. The upper buried forest was formed as a result of sea level changes and dated from the Early Jomon Period of middle Holocene. Picea and Larix dominated in the lower and middle buried forests of the Last Glacial Maximum and the Late Glacial Period, accompanied by occasional Abies. In the middle buried forest Picea and Larix grew evenly intermixed, and Larix trees were larger (up to 84 cm in stem diameter) than Picea trees (up to 33 cm in stem diameter). The taxonomic composition of the lower and middle forests was similar to that of the buried forests on the eastern slope of the Towada Volcano of the Late Glacial Period. The buried forests of northern Honshu Island, as well as those of south to central Honshu Island, indicate that Picea–Larix forests were the dominant vegetation through the Last Glacial Maximum to the Late Glacial Period on central to northern Honshu Island. In the upper buried forest of the middle Holocene, Fraxinus and Alnus dominated, accompanied by Juglans, Castanea, Quercus, Fagus, Magnolia, Hydrangea, and Acer. This upper buried forest contemporaneously formed woody peat below the forest floor. According to a pollen analytical study at Ooyazawa, similar buried forests continually established themselves after frequent destructions by flooding for at least 1000 years of middle Holocene. Lowland forests of Fraxinus and Alnus that simultaneously formed woody peat grew extensively in the Kanto Plain of central Honshu Island during the middle Holocene. The upper buried forest at Ooyazawa was the first record of this type of lowland forest outside the Kanto Plain and showed that the establishment of marsh forests with contemporaneous woody peat was a general phenomenon in a large area of Honshu Island during the middle Holocene. [Copyright &y& Elsevier]

The article offers information on radiocarbondated charcoal fragments recovered from soils as proof to the claims of uncovering Pleistocene forest microrefugia in the Landes de Gascogne, Western France. It mentions the persistence of Fagus sylvatica or beech in situ in several microrefugia through full glacial and interglacial periods. It is inferred that the dated charcoal evidence is not enough proof to claim the Pleistocene forest microrefugia within a periglacial desert.

ABSTRACT Loess consists of silt-dominated sediments that cover ~10% of the Earth's surface. In southern South America it occurs in Argentina, Bolivia, Paraguay and Uruguay, and its presence in southern Brazil was never studied in detail. Here is proposed a new lithostratigraphic unit, Cordão Formation, consisting of loess deposits in the southern Brazilian coastal plain. It consists of fine-very fine silt with subordinate sand and clay, found mostly in lowland areas between Pleistocene coastal barriers. These sediments are pale-colored (10YR hue) and forms ~1,5-2,0 meter-thick stable vertical walls. The clay minerals include illite, smectite, interstratified illite/smectite and kaolinite, the coarser fraction is mostly quartz and plagioclase. Caliche and iron-manganese nodules are also present. The only fossils found so far are rodent teeth and a tooth of a camelid (Hemiauchenia paradoxa). Luminescence ages indicate that this loess was deposited in the latest Pleistocene, between ~30 and 10 kyrs ago, and its upper portion was modified by erosion and accumulation of clay and organic matter in the Holocene. The estimated accumulation rate was ~630 g/m2/year. The probable source of this loess is the Pampean Aeolian System of Argentina and it would have been deposited by the increased aeolian processes of the last glacial.