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The Muravian interglacial horizon is the last warm period of time span closest to our time, as well as one of the marking horizons in the complex composed layer of Quaternary deposits in Belarus. The study of the Muravian deposits, as well as an elucidation of the paleogeographic conditions that existed at that time, can make it possible to predict climate changes on our planet in the future. Based on the analysis of palaeocarpological materials obtained by the author in the study of reference sections located within the territory of the Belarusian upland and reflecting the optimal phases of the Muravian interglacial, a brief analysis of the composition of fossil floras is carried out, the conditions for their formation are established, and paleoclimatic reconstructions were performed on the basis of the obtained materials. The data obtained indicate that the average July temperatures at the optimum of the Muravian interglacial on the territory of the Belarusian upland were +17.0 till +24.0 °С for the eastern regions and +17.0 till +21.2 °С for the Grodno upland. The average January temperature ranged from +2.0...+7.0 to –3.0...–7.2 ºC. The results obtained are in good agreement with the data of other methods, in particular, palynological analysis based on the study of fossil pollen and spores. In accordance with the modern climatic indicators of the territory of Belarus, the climate at the optimum of the Muravian interglacial was at least several degrees warmer than the current one, and the winters were much milder.

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It is widely recognized that fossil leaves are good proxies for paleoclimate estimates, and leaf physiognomy analysis is a traditional technique used to make climate estimates. There are only a few paleoclimate reconstructions for the southern part of South America based on this technique. Here we report climate parameters using fossil leaves from the Río Turbio (Eocene-Oligocene) and Río Guillermo (Oligocene-early Miocene?) formations in southern South America, Cuenca Austral, Argentina. We used univariate (leaf margin and leaf foliar area analysis) and multivariate methods (CLAMP, DiLP) on two datasets from South America, in the Southern Hemisphere. Lower and upper members of the Río Turbio Formation show a mixed paleoflora represented by paratropical as well as cool-temperate taxa such as Nothofagus, with a similar percentage of untoothed fossil leaves. Climate estimates indicate warm and humid conditions for both Río Turbio Formation members. The Río Guillermo Formation is represented by mostly cool-temperate elements, mainly Nothofagus, and most with toothed margins. The paleoclimate analysis indicates a decrease in temperature and precipitation when comparing the two studied formations. Today, temperate forests in southern Argentina have a plant composition and climate more similar to the estimates made for the Río Guillermo Formation. [ABSTRACT FROM AUTHOR]

The relevance of the research is caused by the need to improve a technique of assessing the hydrocarbon resources by the volume and genetic method based on paleoreconstruction of geotemperature mode of petromaternal deposits. The main aim of the research is to assess the influence of the century course of temperatures on Earth surface on geothermal mode of petromaternal deposits of the southeast of Western Siberia, on the extent of realization of their generative potential. Objects of researches: average annual temperatures in the Mesozoic and the Cenozoic of the southern paleoclimatic zone of Western Siberia, Bazhenov deposits of the Mesozoic and Cenozoic section opened with deep wells at latitudes of Tomsk and Novosibirsk areas. Methods of researches: the analytical report of reconstruction of the century course of temperatures on a day surface in the Mesozoic Cenozoic executed with application of an actualistic method; a method of paleotemperature modeling for a quantitative assessment of influence of a paleoclimate factor on the geothermal mode of maternal deposits and intensity of generation of hydrocarbons. Research results. The authors have synthesized the geographical and geochronological of the data on the century course of temperatures on Earth surface of the southeast of Western Siberia published in the period of 1974-2011. The data were obtained by a number of authors on the basis of the comparative-historical analysis of sedimentary thicknesses lithology, flora areas, and materials of isotope and magnesia thermometry. For the southern paleoclimatic zone (Tomsk, Novosibirsk and Omsk areas) the «local» century course of temperatures on a terrestrial surface, since the Jurassic time, was constructed. By geotemperature criterion the authors allocated the centers of intensive generation the Bazhenov oil by paleotemperature modeling of sedimentary cover, including petromaternal deposits; calculated and the analyzed the distribution of oil resources relative density. The quantitative assessment of paleoclimate influence on geothermal mode and extent of realization of generative capacity of the Bazhenov suite, the hydrocarbons of petroleum potential complexes of Tomsk and Novosibirsk oil fields forming deposits was received. It is shown that without considering paleoclimate it is impossible to restore adequately thermal history of maternal deposits that may underestimate to 2 times or more the value of the estimated resources by a volume and genetic method. Use of the "local" century course of temperatures on the Earth surface increases the efficiency of technology for defining the expected resources, allows considering more correctly the history of the main phase of oil formation, both without overestimating/underestimating (to 30-40 %) the settlement resources. The paper demonstrates the continuity and scientific and practical importance of combination of a comparative-historical (actualistic) method of classical geology and a new method of exploration geophysics - geothermics - when solving the problems of assessing hydrocarbon resources.

We describe a new species of mastodonsauroid temnospondyl from Algeria, Stanocephalosaurus amenasensis nov. sp., on the basis of two exquisite skulls from a Lagerstätte found in the lowermost formation of the Zarzaïtine Series, Illizi Basin, in the area of “La Reculée”, In Amenas region, Algeria. The new species is characterized by subtriangular nostrils with concave lateral borders; small orbits; postfrontals posteriorly very wide; very elongate parietals; smoothly concave posterior margin of the skull; ovoid anterior palatal vacuities; very posteriorly pointed choanae; oval interpterygoid fenestrae; and a short anterior extension of the cultriform process of the parasphenoid. S. amenasensis is different than the Algerian taxa previously erected by Lehman (1971)–“ Parotosaurus lapparenti ” and “ Wellesaurus bussoni ”–which we consider nomina dubia . It enlarges the distribution of the genus in northern Gondwana and supports the Early-Middle Triassic age of the lowermost formation of the Zarzaïtine Series. It also suggests that the local palaeoclimate was very seasonal and these aquatic amphibians died massively in a dewatering sebkha. [ABSTRACT FROM AUTHOR]

We have analyzed the palaeoenvironment and palaeoclimate of the beginning of the Holocene in the Iberian Peninsula on the basis of the small-mammal assemblages from three sites within the geography of the Iberian Peninsula: Mirador (Sierra de Atapuerca, Burgos), Colomera (Sant Esteve de la Sarga, Lleida) and Valdavara-1 (Becerreá, Lugo). These associations reveal that the palaeoenvironment was more humid than today in the sites under study, and the landscape was dominated by woodland and woodland margins in all the studied layers. Further, the climatic conditions were stable, but with winters colder than at present, above all in the Mediterranean area. Finally, our data have been compared with other environmental and climatic proxies, showing that human activities exerted little impact on the palaeoenvironmental conditions that occurred from 7000 to 3000 BP in the Iberian Peninsula. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: We explore the role of continental drift on the Phanerozoic evolution of the carbon cycle and climate with the GEOCLIM numerical model. GEOCLIM couples a 3D-climate model, a global dynamic vegetation model and a mathematical description of the chemical weathering of the continental surfaces. Twenty-one timeslices covering the whole Phanerozoic are simulated, allowing the calculation of the climate and steady-state atmospheric CO2 for each of these timeslices. We show that continental drift is a first order control parameter of the geological carbon cycle and climate. The salient features are the following: (1) the Paleozoic environment is characterized by a long term CO2 decrease; (2) the Late Permian-Late Triassic period displays very high CO2 levels; (3) atmospheric CO2 is decreasing since the Middle Cretaceous. All these features are driven by the drift of the continents and the subsequent modulation of the water cycle and weathering rates. Furthermore, continental drift imprints the long term evolution of the tropical seawater surface temperatures with periodical oscillations characterized by a frequency of about 120 Myr, in agreement with available data. Finally, we emphasize a discrepancy existing between the climate reconstructions from the most recent apatite δ18O data and the CO2 inferred from proxies. Reconstructed CO2 levels from proxies are often unrealistically low for the distant geological past. [Copyright &y& Elsevier]

Abstract: The Çal Basin formed in the late Miocene as an orogen-top rift hosting terrestrial sedimentation. The initial array of alluvial fans in a half-graben basin was replaced by an axial meandering-river system during the late Tortonian. Palaeomammal taxa indicate a mid-Turolian age of the deposits and a grass-dominated steppe ecosystem. Isotopic data from pedogenic carbonates indicate a warm, semiarid to arid climate. Subhumid to humid climatic conditions prevailed in the Pliocene, with a palustrine environment and savannah-type open ecosystem, recording a regional response to the marine flooding that terminated the Messinian ‘salinity crisis’ in the Mediterranean. Pleistocene saw re-establishment of a fluvial system in the basin with the development of an open steppe ecosystem in warm, semiarid to arid climatic conditions. The sedimentary facies analysis of the basin-fill succession, combined with biostratigraphic data, render the basin a regional reference and help to refine the Neogene tectono-climatic history of SW Anatolia. [Copyright &y& Elsevier]

Abstract: Here we present the first palaeoenvironmental and palaeoclimatic analysis based on a study of the microvertebates of the Sala de las Chimeneas (Maltravieso Cave, Cáceres). The fauna is ascribed to the end of the Late Pleistocene, as indicated by the presence of Microtus (Iberomys) cabrerae, Microtus agrestis and Arvicola terrestris and by absolute datings of ∼ 17 ka BP. The palaeoenvironmental analysis points to a setting within the early part of the Last Glacial Maximum (LGM), with a habitat dominated by woods and humid meadows, a climate (mean annual temperatures) colder than at present (−4°C), and mean annual precipitation markedly higher (+700mm) than is currently the case in the area around Cáceres. These data provide new information on the impact of the last cold spells of Marine Isotope Stage 2 (MIS 2) in the Southwest of Europe, in a region where no studies of the microvertebrates of this period had previously been undertaken. [Copyright &y& Elsevier]

Abstract: This paper proposes a new reflection about the late Pleistocene climate impact on the iberomausian coastal expansion. A recent advancement of palaeoenvironment knowledge allows us from now to apprehend a context and circumstances in which are developed diverse late Pleistocene cultures in the Maghreb. This article tries to understand a cultural dynamic of this period by the light of a contemporary climatic evolution. [Copyright &y& Elsevier]

Abstract: The Valdavara-1 cave, located in the westernmost part of the Iberian Peninsula, is an archaeological site that has been excavated since 2007. At least two main sedimentary units have been identified: an upper one, 30 cm-thick, that has yielded many fragments of ceramic characteristic of the Recent Prehistory (with a radiocarbon age of 4.490±40years BP), and a lower one, 90 cm-thick, separated from the upper one by an erosive discontinuity and late Pleistocene in age (radiocarbon ages between 13.770±70 and 15.120±70years BP). The small-vertebrate assemblages recovered from the sieving-washing of all the sediment from the excavation campaigns include a total of at least 34 taxa (six amphibians, nine squamate reptiles, five insectivores, two chiropterans and 12 rodents). The materials from this locality constitutes the first mention in northwestern Spain for Microtus (Iberomys) cabrerae and Micromys minutus, currently absent from this area, as well as the first mention in the fossil record for Chioglossa lusitanica, Discoglossus galganoi and Chalcides striatus. In both layers, such small-vertebrate associations suggest a patchy landscape dominated by humid meadows and woodland areas, with the existence of water areas in the vicinity of the cave. The climate shows a more continental pattern during the late Pleistocene, as evidenced by the presence of Microtus arvalis, Sorex minutus and Rana temporaria, and was milder during the Recent Prehistory, with the occurrence of typically Mediterranean taxa such as Crocidura russula, Chioglossa lusitanica, Discoglossus galganoi, Rana iberica, Chalcides striatus and Timon lepidus. The amphibian and squamate associations suggest that the climate change recorded at the Valdavara-1 cave between the latest Pleistocene and Holocene levels may correspond to a difference of 0.8°C in terms of mean annual temperature, although the difference is 2.8°C for the mean temperature of the coldest month. [Copyright &y& Elsevier]

Abstract: Within the framework of the European Commission''s program “Patine du Desert” (DG Research; INCO-CT-FP6-2004-509100), partially concerning the preservation of Saharan engraved rock art, the approach led to the study of the sandstone patina from the rock art site of Oum La Leg (Anti-Atlas, Morocco). The rock and its Tazina school engravings are sometimes covered with a thin brown-ochre coating which only shows a dark patina, the desert patina. This film corresponds to a weathering cortex whose formation is contemporary with wet events from the Holocene period. On the surface, the patinas’ diversity is linked to the heterogeneous distribution of manganese oxides (birnessite and todorokite) due to a reorganisation which led to the incorporation of aeolian silts. Some dating suggestions are made to establish an ante quem age for the engraved lines. [Copyright &y& Elsevier]

Abstract: Situated a few kilometres from Angles-sur-Anglin (Vienne, France), the Roc-aux-Sorciers cave has yielded in 1927 and 1950 industry of the Middle and Upper Magdalenian periods. Our analyses of the sedimentary filling, dated from isotope stage 2, demonstrate the existence of two climatic sequences in the six ensembles defined during the excavations. A first sequence, at the base of the cave filling, corresponds to the occupation levels of the Middle Magdalenian and of the early Upper Magdalenian. At that time, the climate was globally cold and particularly humid, a conclusion that does not support Bastin''s 1975 hypothesis on the oscillation of Angles-sur-Anglin, which postulates a mild and humid climate. In fact, the climate evolved progressively towards a slight warming from the base to the top of the stratigraphy. During the second sequence, corresponding to the occupation period of the Upper Magdalenian, the relatively stable climate was slightly warmer and quite humid. Stratigraphical and sedimentological data thus provide new information on the conditions under which the filling was deposited and on the palaeoclimatology of the Poitou-Charentes region during Magdalenian occupation. [Copyright &y& Elsevier]

Abstract: This article reports a new record of the greater noctule Nyctalus lasiopterus (Schreber, 1780) in the Late Pleistocene of Europe. A fragment of a left mandible from this species was collected in Layer O (around 55 ka) from the Abric Romaní rock shelter, providing evidence of the presence of the greater noctule in north-eastern Spain during the latest Late Pleistocene. The relevance of this new record, which is geographically not reported up to now in the area, is discussed in terms of environmental changes. [Copyright &y& Elsevier]

Abstract: Pollen studies from core SO90-56KA recovered from the Arabian Sea off the Makran Coast (24° 509N, 65° 559E; 695 m depth) show that the end of the Holocene Humid Period, linked to the weakening of Indian monsoon fluxes, took place between 4700 and 4200 BP. Two periods of strong summer monsoon activity are identified between 5400–4200 BP and 2000–1000 BP during which the montane pollen taxa coming from the Himalayas reached the Makran coast due to increased fluvial activity of the Indus River. A contrasting period, dominated by the winter monsoon between 4200 and 2000 BP, is identified based on the presence of pollen taxa from the Baluchistan plateaus. The regional vegetation of the low- and midaltitudes, arid and semiarid, are remarkably stable from 4500 BP to the present. [Copyright &y& Elsevier]

Abstract: Using an Atmospheric Global Circulation Model, we assess the relevance of selected atmospheric mechanisms for climate evolution of Saharan and sub-Saharan regions since the Miocene. First, we test the influence of the East-African Rift System uplift on atmospheric dynamics. Although the uplift played an important role in triggering East-African rainfall, no significant impact over central and western Africa has been detected. We also analyse the feedbacks of a giant lake on the climate of Chad basin. First results infer a negative feedback of the giant lake on the water balance, as convection is weakened by the cold water surface and as water evaporated from the lake does not feed the basin hydrological cycle. Lastly, we suggest that colder than present sea surface temperatures over the Gulf of Guinea reinforce the West-African monsoon, by enhancing the moisture advection engine via stronger thermal contrast between the ocean and the continent. [Copyright &y& Elsevier]

Abstract: During the last million years, interglacial periods were characterized by sea level, Antarctic air temperature and atmospheric CO2 concentrations different from those of today. The relationship between CO2 and climate remained rather constant over these intervals, which confirms that CO2 acts as a positive feedback to insolation forcing. The thermohaline circulation and the Atlantic meridional overturning are sources of another strong positive feedback mechanism. They have been responsible for the partial melting of the West Antarctic Ice Sheet during the last interglaciation and for the amplification of the insolation forcing to trigger the last glacial inception. [Copyright &y& Elsevier]

Abstract: In order to reconstruct the past variations of the Southeast Asian monsoon intensity and estimate the sedimentary system reactivity to climatic changes in Southeast Asia over the last 450kyr, mineralogical and sedimentological analyses have been performed on the terrigenous fraction of the South China Sea sediment. End-member modelling coupled with grain size data discriminates three end-members that determine the nature and intensity of the main sediment transport vectors. Low sea-level stands are characterized by sediment reworking that allows transportation of a coarse end-member (20–40μm) to the deep-basin. By contrast, the other end-members (4–6μm; 9–13μm) are controlled by the shoreline position (sea level) and/or by changes of the rivers capacity transport (monsoon). Finally, aeolian input to the northern margin of the South China Sea can be considered negligible compared to the massive fluvial input and the reworking of the sediments. [Copyright &y& Elsevier]

A comprehensive review of Holocene paleoenvironmental data has been prepared, providing the basis for evaluating natural variability in climate and ecosystem dynamics in the northern Columbia River basin. The paleoenvironmental record reveals four major climatic shifts and a number of less well-defined climatic changes throughout the Holocene. The major climate changes are (1) a cool or cold, late-glacial climate at the end of the last glaciation (>11 500 cal. year BP), (2) an interval of drought and maximum summer warmth during the early Holocene (ca. 10500 to 8000 cal. year BP), (3) a mid-Holocene trend towards a cooler, more moist climate (ca. 8000 to ca. 4000 cal. year BP), and (4) a relatively stable climate persisting from ca. 4000 cal. year BP until the arrival of European settlers. Air temperatures have warmed by about 1 °C over the past century. Minor climate events that are emerging as global in nature include Little Ice Age (1200–150 BP) conditions, and a late Holocene cool wet period (3500–2500 BP). These are observed in some study sites examined in this paper and may be related to large-scale cycles of 2800–2000 and 1500 years. A discussion of changing atmospheric circulation patterns, and the causes of long-term climatic change are included, together with a discussion of the implications of the paleoenvironmental record for understanding future climate, and the likely response of communities and ecosystems. [ABSTRACT FROM AUTHOR]

Copyright of Revue de Micropaleontologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The late Early–Middle Miocene sequences of the Seyitömer Basin (western Anatolia) were palynologically investigated. Fifty-five taxa belonging to seven gymnospermous and 48 angiospermous pollen genera were identified in the 19 productive samples. Two pollen zones were recognised based on the changing abundance of individual tree taxa. Zone 1 is characterized by predominance of Pinus and Cedrus. Zone 2 is characterized by predominance of deciduous Quercus and evergreen Quercus and a marked reduction in representation of Taxodiaceae. The differences in the pollen spectra between Zone 1 and Zone 2 may reflect the global Middle Miocene cooling. These results are largely comparable to pollen data derived from the neighbouring areas. The vegetation of the Seyitömer Basin was dominated by trees. This palynological analysis reveals the existence of a swamp-forest developed in a subtropical to warm-temperate humid climate. [Copyright &y& Elsevier]

Abstract: What truly happened in the terrestrial ecosystems in response to the famous Messinian salinity crisis is still the matter of extensive discussions. Did mammals record any faunal and/or a climatic or environmental fluctuation is a question that still remains open. Our objective is to investigate mammalian faunas before, during and after the crisis within different terrestrial basins surrounding the Mediterranean Sea. We therefore apply here two methods, the cenogram method and a transfer function based on murine (rodents) species richness to better understand if our proxies can record any qualitative or quantitative climatic or environmental change. The results indicate that mammal faunas do not record any particular shift in climate or environment at the scale of the whole peri-Mediterranean area. The trend is different at the regional scale of terrestrial basins as temperatures increase (Calatayud-Daroca-Teruel Basin) or decrease (Languedoc-Roussillon region) punctually occurs just after the crisis; stable conditions in different areas (e.g. Greece) contradict these trends. Biases in the fossil record or in the methodologies could produce such discrepancies. [Copyright &y& Elsevier]

Abstract: At the end of the Neoproterozoic, the Earth may have experienced important environmental changes, with a transition between two supercontinents (from Rodinia to Gondwana), extensive glaciations with ice caps reaching the Equator and the beginning of metazoan diversification. In such a context, the palaeomagnetic record can be used to constrain both the palaeogeography and the palaeoclimate (palaeolatitudinal distribution of glacial deposits). Here we present an up-to-date geochronological and palaeomagnetic database for the Neoproterozoic glacial deposits, including poles recently obtained on ‘cap carbonates’ from China, Oman, and Amazonia. The database comprises ten poles (from eight different cratons), obtained directly on the glacial deposits or on the overlying ‘cap carbonate’, and two other palaeolatitudes derived from reference poles coeval to well-dated glacial units in the same craton. The occurrence of glacial deposition at low latitudes (<30°) is attested by some good-quality poles, two of them well dated at ∼740 and ∼635Ma. Based on these poles and on reference poles obtained on igneous rocks, tentative palaeogeographic reconstructions for ∼750, ∼620, and ∼580Ma (ages for which the database has limited but still sufficient entries) were performed in order to investigate the tectonic context within which the glacial events were produced. [Copyright &y& Elsevier]

Abstract: The timing of desertification of the Sahara Desert is poorly understood, with recent estimates indicating an onset of hyper-aridity during the Latest Miocene. Field work in Egypt in 2005 has led to the discovery of evidence that indicates that 11–10 Ma the Western Desert was covered in woodland. Fossiliferous cave breccia at Sheikh Abdallah, Western Desert, Egypt, has yielded a Late Miocene (11–10 Ma) microvertebrate fauna, which contains Galagidae, Microchiroptera, Macroscelididae, Soricidae, Erinaceidae, and Rodentia. The locality also yielded the remains of frogs, snakes, lizards, and birds. The fauna indicates a mean annual rainfall in excess of 500 mm and perhaps as much as 1,200 mm. This palaeoclimatic information is important because it reveals that the Sahara Desert, which is today the largest in the world, was either considerably smaller during the Late Miocene than it is today, or that it did not yet exist as a continuous hyper-arid belt right across the continent. This data accords with estimates of a Latest Miocene (8–7 Ma) increase in aridity in the Sahara. To cite this article: M. Pickford et al., C. R. Palevol 5 (2006) . [Copyright &y& Elsevier]

Copyright of Revue de Micropaleontologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: This study concerns a core collected in Brejo do Espinho''s lagoon from Cabo Frio littoral (Brazil) submitted to dry influence of local upwelling controlled by north-east trade winds from the South Atlantic and particularly strengthened during El Niño events. Diatoms study supported by sedimentological and isotopic analyses shows dry phases infrequent before 4000 yr, a highly variable climatic phase between 3600 and 2900 yr and from 2400 yr onward a dryness enhancement. To cite this article: B. Laslandes et al., C. R. Geoscience 338 (2006). [Copyright &y& Elsevier]

Abstract: Quaternary climate and atmospheric composition: new ice cores. Over the last 20 years, studies of Antarctic and Greenland ice cores have provided a wealth of information directly relevant to the past and to the future evolution of our climate with, as more important, the discovery of a link between greenhouse gases and climate in the past and the characterization of rapid climate changes. These results are based on the analysis of deep ice cores such as the one drilled at the Vostok site, which allows us to describe the evolution of Antarctic climate and of atmospheric composition over 420 ka (thousands of years), and GRIP and GISP2 (Greenland), which precisely depict the rhythm of rapid changes during the last 100 ka. Information available from ice cores has considerably increased in 2004 thanks to the EPICA Dome C ice core in Antarctica and to the North GRIP one, in Greenland. We present these two successful international programs and describe the first results they have provided, with the EPICA Dome C core covering eight climatic cycles (800 ka) and the North GRIP one allowing us to reach, for the first time from a northern-hemisphere ice core, the Eemian, the warmest past of the last interglacial around 120 ka ago. To cite this article: J. Jouzel, C. R. Palevol 5 (2006) . [Copyright &y& Elsevier]

Abstract: The Early Triassic interval is dominated by unusual oceanic and climatic conditions that are perhaps unique to the Phanerozoic. Early Triassic oceans were likely anoxic and possibly alkaline while climate during the period was dominated by the expansion of deserts and the migration of warm, moist conditions to high Southern Hemisphere latitudes. Atmospheric O2 levels apparently decreased during the period while CO2 levels increased. The unusual and severe nature of many aspects of Early Triassic oceans and climate likely played a role in determining the timing and shape of the biotic recovery from the Permian–Triassic mass extinction. To cite this article: A.D. Woods, C. R. Palevol 4 (2005) . [Copyright &y& Elsevier]

Abstract: During the last glacial, characterized by a rapid climatic variability, the Greenland ice isotope–temperature relationship is biased due to changes in the hydrological cycle. An alternative palaeothermometry method, based on air isotopes, N and Ar, provides quantitative estimates of rapid temperature increases and suggests a different shape of rapid events compared to water isotope profiles. The temperature over five Dansgaard–Oeschger events (DO) on the NorthGRIP ice core is reconstructed: DO 18, 19, 20, 23 and 24 associated with warming events of 11, 16, 11, 10 and 16 °C, i.e. roughly twice larger than the amplitude suggested by the water isotopes. Together with similar efforts, our measurements permit to show a large variability between the different DO. To cite this article: A. Landais et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

Abstract: On the 102- to 103-year timescale, internal reorganizations of the climate system result in abrupt climatic changes of great magnitude. Although a large body of data has been obtained, the physical mechanisms responsible for these changes are still poorly understood. Instrumental data are too short to fully record the variability of the climate system. Palaeoclimatic records provide estimates of the past atmospheric composition, temperature, precipitation, vegetation, extension of glaciers, and past ocean circulation. On the 104- to 106-year timescale, the astronomical theory of palaeoclimates accounts for most of the reconstructed variations. To cite this article: J.-C. Duplessy et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

Abstract: Typical rapid climate events punctuating the last glacial period in Greenland, Europe and Antarctica are compared to two rapid events occurring under warmer conditions: (i) Dansgaard–Oeschger event 25, the first abrupt warming occurring during last glacial inception; (ii) 8.2 ka BP event, the only rapid cooling recorded during the Holocene in Greenland ice cores and in Ammersee, Germany. The rate of warming during previous warmer interglacial periods is estimated from polar ice cores to 1.5 °C per millennium, without abrupt changes. Climate change expected for the 21st century should however be at least 10 times faster. To cite this article: V. Masson-Delmotte et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

Abstract: Holocene millennial climate variability is smaller than that of the last glaciation, due to the disappearance of large unstable ice sheets. Marine records show that the sea-surface temperature (SST) exhibited small variations, mainly in the high and low latitudes. They may be interpreted as a linear response to the mean annual insolation. Major changes in the hydrological cycle have been evidenced in the Asian and African monsoon area, resulting in enhanced precipitation and large river outflow in the Bay of Bengal and the Gulf of Niger. Enhanced rainfall over the Mediterranean Basin resulted in a weak circulation and sapropel formation below 800-m water depth in the eastern Mediterranean Sea. Finally small changes in the thermohaline circulation and the warm North Atlantic Drift have been detected in the Nordic Seas. The Holocene climatic variability is therefore similar to that of the Quaternary, but with small amplitude, while continents experienced large rainfall variations. To cite this article: J.-C. Duplessy et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

Isotopic measurements in polar ice core have shown a succession of rapid warming periods during the last glacial period over Greenland. However, this method underestimates the surface temperature variations. A new method based on gas thermal diffusion in the firn manages to quantify surface temperature variations through associated isotopic fractionations. We developed a method to extract air from the ice and to perform isotopic measurements to reduce analytical uncertainties to 0.006 and 0.020‰ for δ15N and δ40Ar. It led to a 16±1.5 °C surface temperature variation during a rapid warming (-70 000 yr). To cite this article: A. Landais et al., C. R. Geoscience 336 (2004). [Copyright &y& Elsevier]