eemian cooling in the norwegian sea and north atlantic ocean preceding continental ice sheet growth changing conditions in the north atlantic region may drive global climate changes1 2 according to previous reconstructions of the last interglacial the eemian north atlantic sea surface tempera tures ssts were similar to present day values3 in the norwegian sea even warmer conditions appeared as a single pulse of short duration4 5 whereas the greenland ice record suggests that the warm interglacial air temperatures were interrupted by several cold periods6 here we use faunal and stable isotope analyses of foraminifera in two sediment cores from the north atlantic ocean and norwegian sea to reconstruct high resolution records of sst and sea surface salinity sss during the eemian interglacial our results which differ significantly from the greenland record6 show a sharp decrease in sst and sss of the norwegian sea associated with a more moderate cooling and freshening of the north atlantic at the middle of isotope substage 5e several millennia before the beginning of continental ice sheet growth changes in the norweg ian sea surface conditions appear to have represented an important climate change affecting global atmospheric and thermohaline circulations

oxygen and carbon isotope signatures in late neogene horse teeth from spain and application as temperature and seasonality proxies abstract here we describe a data set of 249 stable o and c isotope compositions from fossil horse teeth from the upper neogene of central spain and discuss their potential as environmental proxies it has been shown before that horse tooth enamel 18 o is a good proxy for local meteoric water 18 o h2o which in turn bears a distinct relation to temperature during precipitation formation at mid to high latitudes we discuss the reconstructed 18 o h2o values and apply modern 18 o h2o temperature equations for the iberian peninsula to these values results for the early pliocene suggest mean annual temperatures up to 2 3 c higher than today fitting pollen based estimates fairly well temperatures 5 c higher than today are predicted for the early late miocene 11 9 ma these estimations are feasible given the local occurrence of crocodilians and the presence of fruit eating hominids in iberia at that time the estimated amount of cooling since then is similar to the estimated decrease in nw europe based on plants the stable carbon isotope record indicates the virtual absence of c4 plants pointing to an environment consisting of c3 plants under slightly water stressed conditions the long term 13 c trend follows the expected decrease in average global 13 c co2 predicted from planktonic foraminifers within tooth variability is supposed to reflect seasonal change but the amplitude is expected to have been significantly damped by internal time averaging effects related to the mixing with atmospheric o 2 reservoir dynamics enamel maturation and sampling procedure the exact degree of damping is difficult to estimate but theoretical considerations suggest values between 50 and 75 depending on temporal resolution and element used c o reconstructed seasonal temperature ranges for central spain are equal or slightly less than the modern range within tooth 13 c variation is more difficult to explain as it can be attributed to multiple factors such as intra annual changes in 13 c co2 micrometeorology plant response and diet the occurrence of both positive and negative intra tooth 18 o 13 c correlations may be related to orbitally forced variations in seasonality

reconstructing biomes from palaeoecological data a general method and its application to european pollen data at 0 and 6 ka biome models allow the results of experiments with atmospheric general circulation models to be translated into global maps of potential natural vegetation the use of biome models as a diagnostic tool for palaeoclimate simulations can yield maps that are directly comparable with palaeoecological pollen and plant macrofossil records provided these records are biomized i e assigned to biomes in a consistent way this article describes a method for the objective biomization of pollen samples based on fuzzy logic pollen types taxa are assigned to one or more plant functional types pfts then affinity scores are calculated for each biome in turn based on its list of characteristic pfts the pollen sample is assigned to the biome to which it has the highest affinity subject to a tie breaking rule modern pollen data from surface samples reflecting present vegetation across europe are used to validate the method pollen data from dated sediment cores are then used to reconstruct european vegetation patterns for 6 ka the reconstruction shows systematic differences from present that are consistent with previous interpretations the method has proved robust with respect to human impacts on vegetation and provides a rational way to interpret combinations of pollen types that do not have present day analogs the method demands minimal prior information and is therefore equally suitable for use in other regions with richer floras and or lower densities of available modern and fossil pollen samples than europe

methodology of the last climatic cycle reconstruction in france from pollen data abstract a numerical method has been devised to reconstruct the climate of the last climatic cycle from pollen data reliable annual reconstructions have been published recently for the two french long sequences of la grande pile and les echets covering the last 140 millennia this paper gives more details on the method used it proposes new reconstructions based on an extended modern pollen data base these reconstructions are consistent with the previous ones especially detailed information is obtained on the seasonal characteristics of climate computations of gcm on the climate variations from 125 kyr to 115 kyr b p are confirmed for western europe the insolation variations have induced at that time a decrease of seasonality accompanied by an increased cyclonic activity in winter this has been the beginning of the first ice growth after the last interglacial other glacier growth phases are detected at the end of substage 5c and particularly at the end of substage 5a

pollen distribution in marine sediments on the continental margin off northern california abstract pollen analysis of 84 samples from surface sediment of the continental margin off northern california between 38 and 39 n and 123 and 124 w shows that the composition of pollen assemblages in this part of the north pacific ocean reflects the regional vegetation of the russian river and other local drainage basins of the northern coast of california systematic trends in the quantitative and qualitative variations in these marine pollen assemblages show that fluvial and marine transport are important factors in determining the nature of pollen assemblages offshore these conclusions are supported by the analyses of pollen in rivers of the north coast of california and in particulate matter collected in a mid slope sediment trap

a new approach for palaeoaltitude estimates based on pollen records example of the mercantour massif southeastern france at the earliest pliocene the altitude of the mercantour massif southern alps france during the earliest pliocene has been estimated using a new quantification method instead of classical methods using geomorphologic criteria our method uses biogeographic and climatologic criteria composition of the modern vegetation belts in the european and peri mediterranean mountains and pliocene annual temperature estimates obtained from fossil pollen data the climatic transfer function indicates for the coastal earliest pliocene of the studied area a mean annual temperature of 16 5oc such a temperature today occurs at 38 5on latitude in the mediterranean region the relation established by ozenda between the present day vertical and latitudinal vegetation assemblages evidences a shift of on average in western europe 110 m in altitude per degree in latitude as a consequence it is possible taking into account that the pliocene lapse rate was almost similar to the modern one to estimate the minimum altitude of the massif at the earliest pliocene the so obtained palaeoaltitude estimate is close to that obtained with the geomorphological method the mercantour massif was almost 2000 meters high at the earliest pliocene

quantifying the eocene to pleistocene topographic evolution of the soutwestern alps france and italy we evaluate the topographic evolution of the southwestern alps using eocene to pleistocene pollen data combined with existing sedimentological petrographic and detrital geo and thermochronological data we report 32 new pollen analyses from 10 sites completed by an existing dataset of 83 samples from 14 localities situated across the southwestern alps including both the pro and the retro foreland basins the presence of microthermic tree pollen mainly abies picea indicates that this part of the mountain belt attained elevations over 1900 m as early as the oligocene inferred rapid surface uplift during the mid oligocene coincided with a previously documented brief phase of rapid erosional exhumation when maximum erosion rates may have reached values of up to 1 5 2km myr slower long term average exhumation rates of 0 3km myr since the late oligocene helped maintaining the high alpine topography of the southwestern alps until today the relative abundances of meso microthermic tree pollen cathaya cedrusand tsuga and microthermic tree pollen abies picea in the pro and retro foreland basin deposits indicate that the present day asymmetric topography with a relatively gentle western flank and steeper eastern flank was established early in the southwestern alps at least since

strong climate coupling of terrestrial and marine environments in the miocene of northwest europe a palynological and organic geochemical record from a shallow marine paleoenvironmental setting in se netherlands documents the coupled marine and terrestrial climate evolution from the late burdigalian 17 ma through the early zanclean 4 5 ma proxy climate records show several coeval variations in both relative sea surface deduced from percent cool dinocysts and terrestrial subtropical vs cool temperate pollen temperature indices the terrestrial climatic trend is confirmed by a quantitative reconstruction of annual mean air temperature based on the distribution of fossil branched glycerol dialkyl glycerol tetraethers showing a cooling from 27 c to 14 c between 17 and 5 ma punctuated by short term variations decreases in sea surface temperature broadly correlate to inferred third order sea level variations and correspond to isotope glacial events mi 3 through mi 7 an additional strong sst decrease occurs around 8 4 ma coincident with a strong reduction and regional disappearance of subtropical pollen types this cooling phase seems associated with lowered sea levels but it has not yet been described from the deep sea 18o record 2009 elsevier b v

regional warming pliocene 3 ma paleoclimate of europe and the mediterranean the paleoclimate of the middle pliocene ca 3 ma was generally warmer than present particularly at middle to high latitudes it has been suggested that this period may represent an analogue for future climate change mechanisms that have been proposed to account for this warming are enhanced thermohaline circulation and or greater concentrations of co 2 in the atmosphere we present new climate model simulations supported by geological data that suggest that in the european and mediterranean region the climate was warmer by 5 c wetter by 400 1000 mm yr and less seasonal than present modeling results suggest that an intensification of the icelandic low pressure system and the azores high pressure system occurred during the middle pliocene as a direct result of higher annual sea surface temperatures and reduced ice cover in the northern hemisphere this change increased the surface pressure gradient over the region and strengthened annual westerly wind velocity by 4 m s 1 associated increases in wind stress by 20 n m 2 over the north atlantic ocean may have enhanced the flow of surface currents such as the gulf stream and north atlantic current which in turn would have sustained the higher sea surface temperatures these changes to the regional climate system would have driven greater atmospheric and oceanic transport of heat from equatorial regions to the north atlantic ocean particularly during winter such conditions are proposed as a likely cause of the warming indicated for europe and the mediterranean ca 3 ma

pliocene and quaternary depositional model of the algarve margin contourite drifts gulf of cadiz sw iberia seismic architecture tectonic control and paleoceanographic insights abstract the contourite drifts off southwest iberia that formed as a result of the interaction of the mediterranean outflow water mow with the continental middle slope were studied in the algarve margin using multichannel reflection seismic lines oil wells piston cores and a bathymetric compilation of four datasets the seismostratigraphic interpretation of a dense array of oil industry seismic and stratigraphic correlation allowed the identification of five seismic units of early pliocene through holocene in the faro and albufeira drifts and four correlative seismic units in the lagos and sagres drifts and three in the portimao drift a three phased evolutionary model for the contourite formation is proposed firstly a precursory phase of pliocene age made up of sheeted drifts represents an initial phase of deposition under bottom current activity that is correlated with the first stages of an enhanced mow at about 3 5 ma secondly the building up phase of early pleistocene age is related to a strengthening of the mow close to the onset of the northern hemisphere glaciations at about 2 6 ma during which were deposited low mounded drifts thirdly the growing phase from middle pleistocene through holocene suggests the presence of a stronger mow since the beginning of the middle pleistocene transition at about 1 3 1 0 ma accounting for the deposition of mounded drifts and formation of the alvares cabral moat seismostratigraphic interpretation and isochron maps allowed for the establishment of the main oceanographic climatic morphologic and tectonic factors that controlled the drifts deposition i the pliocene and quaternary mow circulation forced by climate changes ii the sea bottom topography inherited from the late miocene mainly shaped by the portimao lagos and bartolomeu dias canyons system iii the interaction between along slope and down slope processes since the pliocene and iv pliocene quaternary fault activity and diapirism

continental climate gradients in north america and western eurasia before and after the closure of the central american seaway abstract the gulf stream as part of the atlantic meridional overturning circulation amoc is known as a major driver of latitudinal energy transport in the north atlantic presently causing mild winters over northwestern eurasia the intensity of the amoc throughout the neogene prior to the final closure of the central american seaway cas in the early pliocene is still poorly known but most authors assume that the circulation was considerably weaker than present here we address this issue from a continental point of view we studied the past amoc intensity by analyzing neogene continental climate patterns along north american and western eurasian transects based on a total of 317 palaeofloras thermal latitudinal gradients are reconstructed for three neogene time slices namely the middle miocene late miocene and late pliocene using the coexistence approach to obtain quantitative climate data the obtained proxy based continental temperature gradients are evaluated against data from a selection of published general circulation model gcm simulations for the three time slices studied our study suggests that shallow thermal latitudinal gradients existed in north america and western eurasia throughout the miocene but became strongly steepened in the late pliocene in both miocene time slices studied the higher latitudes were by up to 30 c warmer than present cold month mean also at times with presumed pre industrial co2 such as the late miocene in the late pliocene high latitude the temperature difference with respect to the present had decreased by up to 10 c cold month mean both mean annual temperatures and cold month means of the lower mid and low latitudes were at the present day level throughout all three time slices or even slightly below in both miocene time slices zonal temperature means at both continental transects were similar in the mid and higher latitudes however several northwest european sites reveal very mild winter condition suggesting the early existence of a probably less intense palaeo gulf stream the distinct thermal anomaly annual and cold month means today existing between north america and western eurasia appeared for the first time in the late pliocene attaining about 50 of the present day magnitude this supports the assumption that the amoc intensified after the final closure of the cas during the early pliocene the results obtained from the palaeobotanical proxies are in line with data from coeval marine archives particularly with north atlantic sea surface temperatures ssts inferred from oxygen isotopes however the proxy based thermal gradients are not well reproduced by a selection of gcm simulations due to a well known systematic underestimation of high latitude warming by gcms for the miocene and pliocene time slices

kaolinitic paleosols in the south west of the iberian peninsula sierra morena region spain paleoenvironmental implications abstract this paper studies the physical and chemical characteristics of eight different soil profiles with paleohorizons rich in kaolinites and developed on different lithologies along the southern border of the hercinian iberian peninsula sierra morena region the paleohorizons of four of these soils are defined by low ph levels desaturation of the exchange complex and proportions of kaolinite of over 75 these characteristics are associated with subtropical pedogenic conditions during the pliocene period a further two soil profiles are contemporary and defined by the following features they occupy depression areas the clay fraction is dominated by kaolinites and smectites the exchange complex is saturated and the ph is above neutral values the last two soil profiles are developed on pliocene continental deposits and have more moderate pedogenic features their kaolinite levels are around 50 and their evolution is associated with shorter periods of exposure to these subtropical alteration conditions

plant and micromammal based paleoprecipitation proxies comparing results of the coexistence and climate diversity approach abstract both plant and vertebrate communities have been used to reconstruct paleoprecipitation however direct stratigraphic comparisons between the two types of proxies have hardly been performed which is due to the fact that plant and vertebrate fossils usually do not occur together in single geological beds here we focus on a series of 18 sites from the neogene of europe and anatolia that contain both types of fossils and compare paleoprecipitation predictions produced by the coexistence approach plants and the climate diversity approach micromammals most of the sites have overlapping uncertainty intervals for mean annual precipitation as generated by the two methods pointing to a common precipitation related signal in flora and fauna nevertheless a systematic difference appears to characterize drier sites for which micromammal richness based estimates for annual precipitation tend to be lower than plant based coexistence based estimates driest month precipitations are in agreement for drier sites but strongly differ for wetter sites with micromammal richness based estimates being higher overlap is poor for estimates of wettest month precipitation which are higher when based on plant based coexistence possible sources for a bias towards higher annual values in plants are related to the inclusion of local wetland elements in the analysis and or to a lower taxonomic resolution for pollen and spores compared to macroflora micromammal based annual estimates could be biased towards drier values when smaller samples lack rare species that could be preferentially wet adapted several of the higher driest and lower wettest month micromammal based estimates could result from over extrapolation beyond the calibration domain for arboreality as currently existing in the modern western old world on the other hand the use of several se asian reference taxa could add a high precipitation monsoonal component to the plant based predictions in addition wettest month estimates for both plants and micromammals probably suffer from the poor performance of water excess as a limiting factor an attempt to further increase the predictive power of the micromammal based prediction equations was performed by incorporating non linear terms and by using an extended calibration set including selected plant based precipitation estimates for micromammal assemblages without modern analogue in the western old world proxy inter calibration

pliocene uplift of the massif central france constrained by the palaeoelevation quantified from the pollen record of sediments preserved along the cantal stratovolcano murat area the french massif central is a key basement relief this region experienced an intense period of alkaline volcanism beginning with the cantal stratovolcano at 11 ma and ending at 3 ma to quantify the palaeoelevation of the cantal stratovolcano and to replace it in the frame of the uplift history of the massif central we first reconstructed the vegetation and climate based on a pollen analysis of the murat diatomites which were deposited in a maar lake the vegetation was organized in three different belts a glyptostrobus swamp around the lake a mixed forest and at higher altitudes a conifer forest the climate estimated using the climatic amplitude method indicates temperatures between 11 4 and 17 c using these estimates and comparison with contemporaneous sites we infer a palaeoelevation for murat between 710 and 930 m a s l this site was therefore uplifted by 130 to perhaps 350 m during the early pliocene leading to a reorganization of the drainage pattern and the capture of rivers flowing from the northern edge of the massif central towards the atlantic ocean our study confirms that the cantal stratovolcano was a high volcano 2500 m before its progressive dismantling during glacial episodes in the pleistocene

subtropical climate conditions and mangrove growth in arctic siberia during the early eocene the early eocene ca 56 47 8 ma was an interval of exceptional warmth with reduced pole to equator temperature gradients climate proxies indicate mean annual air temperatures mats and sea surface temperatures ssts exceeding 8 18 c and frost free mild winters in polar areas features that have proven difficult to reproduce with the most elaborate climate models a full appraisal of the early eocene polar climate has been however limited by possible seasonal biases associated with geochemical proxies and the lack of data from the vast eurasian arctic here we present multiproxy data from lower middle eocene coastal plain sediments of the new siberian islands russia showing that taxodioid cupressaceae palms and the mangrove avicennia grew in arctic siberia above 72 n under air temperatures averaging 16 21 c annually and 5 5 14 c in winter kaolinite contents are exceptionally high up to 60 of clay assemblages and comparable to those found in present day subtropical soils formed under high mean annual precipitation map 1000 mm and warm mat 15 c conditions the avicennia pollen records the northernmost mangrove growth ever documented and indicates early eocene ssts exceeding 13 c in winter and 18 c in summer considering the high map estimated for arctic siberia and other pan arctic landmasses we propose that the heat from warm river waters draining into the arctic might have amplified early eocene polar warmth our results provide the first climate constraints for the early eocene of arctic siberia and support the view that most climate models underestimate polar warming in greenhouse conditions

origin and implications of orbital induced sedimentary cyclicity in pliocene well logs of the western mediterranean abstract the climatic origin of astronomically induced sedimentary cycles in the mediterranean and adjacent areas during the late neogene and quaternary remains puzzling as cycles have been linked to concomitant but seasonally opposite changes in african summer monsoon precipitation eastern mediterranean sapropels and atlantic regulated winter precipitation carbonate cycles on the atlantic side of the mediterranean particularly little is known about the cyclic sedimentation on orbital time scales in the western mediterranean with the prime exception of the messinian sapropels from the sorbas basin southern spain here we show that regular alternations in pliocene downhole logs from the industrial drill site muchamiel 1 located along the balearic promontory in the western mediterranean are related to eccentricity bundles and to obliquity and precession cycles basic meter scale alternations we establish an astronomically based age model for the interval between 5 33 and 2 8 ma by first correlating cycle bundles to eccentricity and then the basic dominantly precession related cycles to the 65 n summer insolation of la2004 the striking bed to bed similarities between the muchamiel 1 well logs and other records from both the atlantic margin and the central mediterranean suggest that the same climatic forcing was responsible for the formation of carbonate cycles across the western mediterranean and adjacent atlantic we conclude that formation of alternating carbonate rich carbonate poor beds was controlled by western mediterranean cyclogenetic mechanisms as well as by peri mediterranean precipitation associated with changes in the north atlantic system nas these findings highlight the importance of peri mediterranean precipitation on the sedimentary cyclicity by dictating terrigenous clay supply and potentially on the hydrology of the basin by providing additional freshwater required for sapropel formation consequently cyclic sedimentation in the mediterranean results from the combined effect of precipitation changes driven by i the north african monsoon ii the atlantic system and iii intrabasinal mediterranean atmospheric dynamics

climate and biomes in the west mediterranean area during the pliocene a new pollen derived method of climatic quantification based on the mutual climatic range of plant taxa has been applied to 17 pliocene pollen sequences in the west mediterranean area the latitudinal gradient observed in the pollen data was confirmed by the climatic reconstructions there is a gradient from north to south both for temperatures and precipitation at the beginning of the pliocene 5 32 5 ma the climate in the north mediterranean area was on average warmer and more humid than today respectively 1 4oc and 400 700 mm in the south mediterranean region the climate was both warmer and drier than today respectively equal to or 5oc higher and drier or equal humidity the pollen based climate estimates were then used to reconstruct biomes for the region the results show the occurrence of three biomes the broad leaved evergreen warm mixed forest the xerophytic woods scrub biome and the warm grass shrub biome these biomes are still represented today in the mediterranean region despite different thermic and water conditions

paleoclimatic reconstruction using mutual climatic range on terrestrial mollusks abstract terrestrial mollusks easily identified in quaternary sediments represent a reliable tool for quantitative estimates of environmental parameters our study comparing the species distribution with meteorological parameters in europe shows that mean temperature of the coldest month and annual thermal magnitude are the most important forcing parameters this survey allows us to adapt the mutual climatic range mcr method to terrestrial mollusk assemblages following two main steps a set of assemblages from different european regions northern norway to southern france is used to apply the method to present day mollusks the reconstructed values describe the latitudinal temperature gradient prevailing over europe however the comparison between the reconstructed and the measured values indicates a shift similar to that observed with the same method applied to beetle assemblages thus estimates must be calculated after the reconstruction is tuned with the observations the results from the modern mollusk assemblages indicate that the mcr method can be safely applied to reconstructing temperatures from terrestrial mollusk assemblages in any worldwide quaternary sequence a trial application is made on late pleistocene assemblages from achenheim alsace france

early miocene repetitive vegetation and climatic changes in the lacustrine deposits of the rubielos de mora basin teruel ne spain pollen analysis of a lower miocene succession from the rubielos de mora basin ne spain has been carried out with the aim of reconstructing the flora vegetation and climatic changes previous paleobotanical studies on these sedimentary rocks and adjacent areas interpreted very diverse climates for the early miocene from humid temperate to dry subtropical in this study a rich thermophilous pollen spectrum and a diverse subarid flora including nitraria caesalpiniaceae ephedra and acacia indicative of a dry subtropical climate are identified on the other hand mesothermic taxa with high water requirements are also abundant therefore the pollen assemblages evidence the juxtaposition of very contrasted environments the presence of subdesertic taxa typical of plants growing in the lowlands and conditioned by a long warm dry season together with others with very high water requirements needing constant water this can be explained by the presence of the rubielos de mora lake providing local conditions for developing riparian forests the vegetation was clearly controlled by the water availability under a subtropical and dry seasonal climate pollen changes along the succession which coincide with sedimentological changes are related to climatic variations alternation in pollen taxa thermophilous dry vs mesothermic riparian reflects the influence of the cyclicity of temperature and precipitation on the lake level and vegetation

geochemical appraisal of palaeovegetation and climate oscillation in the late miocene of western bulgaria abstract palaeobotanical methods and geochemical techniques were used to assess plant contribution and palaeoenvironment for the staniantsi basin bulgaria the aim was to connect palaeovegetation change and climate oscillation based on pollen and statistical analysis with organic geochemical proxies for a late miocene lacustrine to paludial sedimentary succession three samples from lignite marl cycles were studied the biomarker assemblage and bulk chemical data indicated that gymnosperms were not important in the palaeomire the presence of des a triterpenoids 17 21 seco triterpenoids hopanes a high content of a d ring monoaromatic hopane and aromatized triterpenoids suggested that photochemical and microbial processes significantly contributed to the alteration of the organic matter om a prolonged period of high water table and severe mechanical destruction promoted microbial activity prior to burial and enhanced decay a geochemical appraisal of short term climate oscillation ca 21 7 kyr was attempted within the limitations of the small number of samples studied the cycles are expressed as lignite marl clay layers combined with cyclic changes in swamp vegetation related to cyclic changes in groundwater level and inundation of the basin in periods of low water level swamp phase lignite accumulation took place preliminary results for selected samples suggest that the oscillation may be reflected in the content of friedelin vs possible degradation products the ratio of a chromatographic peak tentatively assigned as a norfriedel 8 en 10 one to friedelin is proposed as a means of detecting short term environmental cycles where values 1 reflect periods of inundation however time series analysis using densely sampled lignite clay layer oscillations are needed to confirm the value of this biomarker ratio for environmental reconstruction

pliocene shallow water paleoceanography of the north atlantic ocean based on marine ostracodes abstract middle pliocene marine ostracodes from coastal and shelf deposits of north and central america and iceland were studied to reconstruct paleotemperatures of shelf waters bordering portions of the western boundary current system including the gulf loop current florida current gulf stream and north atlantic drift factor analytic transfer functions provided pliocene august and february bottom water temperatures of eight regions from the tropics to the subfrigid the results indicate 1 meridional temperature gradients in the western north atlantic were less steep during the pliocene than either today or during late pleistocene isotope stage 5e 2 tropical and subtropical shelf waters during the middle pliocene were as warm as or slightly cooler than today 3 slightly cooler water was on the outer shelf off the southeastern and mid atlantic coast of the u s possibly due to summer upwelling of gulf stream water 4 the shelf north of cape hatteras north carolina may have been influenced by warm water incursions from the western edge of the gulf stream especially in summer 5 the northeast branch of the north atlantic drift brought warm water to northern iceland between 4 and 3 ma evidence from the iceland record indicates that cold east greenland current water did not affect coastal iceland between 4 and 3 ma 6 middle pliocene north atlantic circulation may have been intensified transporting more heat from the tropics to the arctic than it does today

reconstruction of vegetation transects for the messinian piacenzian of italy by means of comparative analysis of pollen leaf and carpological records abstract the first comprehensive and comparative analysis of the main micro pollen and macro leaves fruits and seeds palaeobotanical data from northern and central italian sites allows four transects of ancient vegetation for the messinian to piacenzian interval to be constructed standard criteria for the reconstruction of vegetation transects are established so that our approach could be extended to other basins or regions bearing neogene palaeofloras and would permit readily comparable reconstructions of past vegetation to be obtained messinian to piacenzian lowland plant communities as reconstructed by means of this integrated and standardized approach show the dominance of warm temperate forest taxa in northern and central italy with the highest floristic affinity to present day forests of the eastern part of central china some panholartic conifers usually interpreted as cool temperate taxa in neogene assemblages are assigned to the upland vegetation they are scarcely represented in messinian and zanclean pollen records with the exception of some intervals characterized by increases in picea and cedrus and almost completely lacking in leaf and carpological ones during the piacenzian notably from 2 8 ma the pollen percentage of such taxa in particular picea progressively increased the overall scantiness of non aquatic herbs not only in the macrofossil record but also in the pollen one indicates the absence of dry conditions and excludes long lasting expansion of open vegetation the type of vegetation subtropical humid forest reconstructed for the evaporitic messinian ca 5 9 to 5 6 ma suggests that the adriatic padane basin would have been under predominant moist conditions even during the deposition of evaporites slightly drier phases in the post evaporitic messinian are suggested at first by the short period of increase of lygeum a steppe plant close to 5 5 ma then by the ecological preferences of some unusual macrofossil taxa cupressus medicago vitex these are however still associated with arboreal plants which require humid conditions definitely indicating that forested environments persisted subtropical sub humid forest the zanclean and piacenzian transects are extremely similar to the evaporitic messinian one and the mesic lowland zonal vegetation can still be defined as subtropical humid forest

a major and long term pliocene intensification of the mediterranean outflow 3 5 3 3 ma ago largely continuous millennial scale records of benthic delta o 18 mg ca based temperature and salinity variations in bottom waters were obtained from deep sea drilling project dsdp site 548 east atlantic continental margin near ireland 1250 m water depth for the period 3 7 3 0 ma ago high epsilon nd values of 10 7 to 9 show that this site monitored changes in mediterranean outflow water mow throughout the mid pliocene bottom water variability at ocean drilling progam odp site 978 alboran sea 1930 m water depth provides a complementary record of mow composition near its west mediterranean source both sites show a singular and persistent rise in bottom water salinities by 0 7 1 4 psu and in densities by similar to 1 kg m 3 from 3 5 to 3 3 ma ago which is matched by an similar to 3 degrees c increase in bottom water temperature at site 548 this event suggests the onset of strongly enhanced deep water convection in the mediterranean sea and a related increase in mow flow as a result of major aridification in the mediterranean source region in harmony with model suggestions the enhanced mow flow has possibly intensified upper north atlantic deep water formation

the use of pollen floras as a tool to estimate palaeoaltitude of mountains the eastern pyrenees in the late neogene a case study northern hemisphere vegetation is generally zoned as a consequence of latitudinal and altitudinal gradients temperature reconstruction from three successive pollen floral assemblages of tortonian messinian and zanclean age from the eastern pyrenees has been used to estimate the altitudinal evolution of the uplifted cerdanya basin and its surrounding massifs a new method has been developed for the uplifted basins which completes that already applied to pollen floras from coastal marine deposits close to mountains in contrast to previous hypotheses it seems that the eastern pyrenees occurred at a lower altitude in the late miocene before continuous uplift began 10 ma ago the rate of this uplift ranged between 0 06 and 0 12 mm yr

do extant nearest relatives of thermophile european cenozoic plant elements reliably reflect climatic signal abstract climatic characteristics of selected extant relatives and analogues for palaeotropical and neotropical european cenozoic plant elements are compared with the proxies derived from comparisons of complete plant assemblages containing the respective elements with analogous extant vegetation the discrepancies obtained may warn us not to lay too much stress on such actualistic data methodologies relying on autecology of the nearest living relatives may thus produce biased and possibly unrealistic proxies the differences in climatic estimates derived from physiognomical methodologies e g leaf margin analysis and clamp may be explained in this way but more studies in approximations between the neogene and extant analogous vegetation and climate are needed to provide more objective data

high resolution palynological analysis in late early middle miocene core from the pannonian basin hungary climatic changes astronomical forcing and eustatic fluctuations in the central paratethys high resolution palynological analysis in the karpatian sarmatian late early middle miocene interval of the borehole tengelic 2 hungary reveals the existence of a forest organized in altitudinal belts developed in a subtropical warm temperate humid climate reflecting the so called miocene climatic optimum pollen changes from the late early miocene to the middle miocene are related to climatic variations values of mean annual temperature ta between 18 and 20 8c and mean annual precipitation pa between 1200 and 1400 mm have been estimated bclimatic amplitude methodq for the badenian decreasing during late badenian and sarmatian ta and pa about 16 8c and 1100 mm have been interpreted as a climatic cooling correlated with the bmonterey cooling eventq and related to the development of the east antarctic ice sheet eais alternation in pollen taxa thermophilous vs altitudinal elements reflects the astronomical forcing on temperature and precipitation and then on vegetation where obliquity and eccentricity cycles dominated eustatic changes determine pinus and pinaceae and dinocyst variations

late miocene early pliocene temperature estimates in europe using rodents studies of mammal communities and in particular of rodents provide useful information on palaeoenvironments and palaeoclimates based on the relationship between species richness and climatic parameters we propose three models using arvicolines murines or sigmodontines in order to quantify past temperatures based on rodents temperatures are estimated here for late miocene early pliocene mn 9 to mn 15 european faunas at a regional scale two kinds of continental patterns in temperatures are observed with homogenous temperatures for mn 9 up to mn 11 or contrasted temperatures at the end of the miocene the onset of a latitudinal effect is also indicated during mn 15 temperature estimates have also been used to infer past elevation for localities

paleoenvironmental evolution of the pliocene villarroya lake northern spain a multidisciplinary approach abstract the pliocene villarroya basin fill consists of lacustrine and alluvial deposits over 100 m thick the lacustrine deposits up to 30 m thick comprise three sequences the two lower sequences consist of profundal laminated deposits formed by mostly terrigenous facies that are overlain by charophytic carbonates and varves the uppermost third sequence made up of massive bioturbated mudstones corresponds to a very shallow lacustrine palustrine environment bulk mineralogy comprises carbonates clay minerals quartz and feldspars the carbonates are exogenic biogenic calcite and biogenic aragonite biogenic calcite constitutes ostracod shells and charophyte stem encrustations whereas aragonite forms gastropod shells and in some varve intervals charophyte encrustations the clay minerals are illite kaolinite palygorskite chlorite and paragonite which are inherited from source rocks and smectite and interstratified clays which are probably formed in the soils of the source area variations in clay mineralogy reflect the interplay between the climate tectonic rejuvenation and the paleogeography of the basin the pollen assemblages indicate significant variations in climate a first phase of varying climate was followed by cool temperate and sub humid phases that culminated in a temperate and dry episode which is recorded in the lower part of the second lacustrine sequence this was succeeded by a marked warm and humid episode which may be correlated with the mid pliocene warmth about 3 0 ma and the subsequent cooling phase which is recorded in the upper third sequence in the two lower sequences profundal lacustrine deposits ostracods indicate oligosaline to mesosaline waters with salinity variations and some warm and na cl episodes molluscs are characterized by hydrobiids suggesting a salinity stress in the upper palustrine deposits the ostracods and aquatic mollusc assemblages indicate fresh cold waters faunal records indicate that changes in salinity do not correlate with climate suggesting phases of significant saline inputs to the lake which were recorded in the lower first sequence and in the upper part of the second sequence the lacustrine sequence of villarroya record pronounced variations in climate and in the lacustrine environment however there are no consistent relationships between the climate conditions inferred from the pollen data and the sedimentary record of the environmental changes showing that other factors especially tectonics have exerted an influence on the paleoenvironmental evolution and on the sedimentary record of the pliocene villarroya lake

habitat responses of fossil plant species to palaeoclimate possible interference with co2 abstract one important tool for palaeoclimate reconstruction uses climate space data of extant species representing the nearest living relatives of fossil taxa under the assumption of taxon specific climate demands remaining unchanged through time this is problematic because the calibration of these proxies is based on current vegetation that has grown under current co2 atmospheric co2 may interfere with taxon specific climate demands particularly water availability because stomatal conductance is negatively correlated with co2 in order to assess direct effects of co2 on gas exchange results of numerous experimental studies are available to provide benchmark data experiments will however always provide data which are restricted to response ranges that living plants are able to express simulation models of plant gas exchange offer additional possibilities to explore the influence of co2 on gas exchange and to consider evolutionary adaptation to gas exchange in this study the potential effects of a changing co2 level on photosynthesis performance under simultaneously changing water availability and temperature is evaluated by using a model based on optimized gas exchange including different scenarios of photosynthesis regulation that may result from evolutionary adaptation the results illustrate the impact of changing co2 on water and temperature demands under these various conditions indicating 1 a particularly substantial influence of co2 under low co2 380 ppm a decreasing influence under further increasing co2 and 3 the relevance of possible evolutionary adaptation of the photosynthetic machinery to a changing co2 level downregulation of photosynthesis for instance leads to a distinctly enhanced response of gas exchange to increasing co2 particularly under low to moderate levels 180 ppm 380 ppm changes in atmospheric co2 therefore adds an additional source of uncertainty to those already considered for nlr based methods it may however also offer new possibilities for palaeoecophysiological research

astronomic timescale for the pliocene atlantic δ18o and dust flux records of ocean drilling program site 659 high resolution benthic oxygen isotope and dust flux records from ocean drilling program site 659 have been analyzed to extend the astronomically calibrated isotope timescale for the atlantic from 2 85 ma back to 5 ma spectral analysis of the 18o record indicates that the 41 kyr period of earth s orbital obliquity dominates the pliocene record this is shown to be true regardless of fundamental changes in the earth s climate during the pliocene however the cycles of sahelian aridity fluctuations indicate a shift in spectral character near 3 ma from the early pliocene to 3 ma the periodicities were dominantly precessional 19 and 23 kyr and remained strong until 1 5 ma subsequent to 3 ma the variance at the obliquity period 41 kyr increased the timescale tuned to precession suggests that the pliocene was longer than previously estimated by more than 0 5 m y

subtropical mangrove and evergreen forest reveal paleogene terrestrial climate and physiography at the north pole sedimentological micropaleontological and geochemical studies of iodp leg 302 boreholes m0004a and m0002a drilled on the lomonosov ridge near the north pole are reported to construct chronostratigraphy and helped unravel paleogene palaeoclimatic these studies concluded to a mean annual temperature of sea surface waters ranging between 21 and 25 c during the paleocene eocene thermal maximum and to the occurrence of episodic ice on the arctic shelf in the earliest mid eocene pollen records are characterised by excellent preservation and identification of 112 taxa reveals a subtropical coastal vegetation comprising taxodium glyptostrobus swamps alternating with avicennia mangrove the hinterland was occupied by a subtropical evergreen forest including engelhardia and distylium occasionally replaced by rhodoleia and castanopsis lithocarpus climate was reconstructed using the climatic amplitude method resulting in the following temperature ranges for low elevations mean annual temperature 18 22 c mean temperature of the coldest month 10 14 5 c mean temperature of the warmest month 26 27 5 c and annual precipitation 1150 1400 mm palaeovegetation data allow us to establish climatostratigraphic relationships with the generalized oxygen isotope curve providing evidence for warm periods e g paleocene eocene thermal maximum petm early eocene climatic optimum eeco mid eocene climatic optimum meco alternating with cooler periods we date the latest record of avicennia mangrove in the arctic basin to the meco the azolla phase did not occur after the eeco but at 50 ma during a climatically unstable episode during the thermal optimum recurrence of rarely produced and weakly transported avicennia pollen the exceptional level of preservation of pollen grains and the high plant diversity indicate that lands of the lomonosov ridge were connected to north america in the ellesmere island region which in addition provided pollen grains of gymnosperms from high elevations these physiographic features suggesting the inflow of altitudinal cold waters into the sea may solve the apparent contradiction between possible sea ice and our reconstructed air temperatures during the middle eocene

vegetation and climate development of the new jersey hinterland during the late middle miocene iodp expedition 313 site m0027 abstract we investigated the palynology of sediment cores from site m0027 iodp exp 313 45 km off the present day coast of new jersey to infer palaeoenvironmental conditions during the second half of the mid miocene climatic optimum and the transition to global cooler conditions in sum 79 taxa were identified via light microscopy 13 gymnosperms 63 angiosperms 3 pteridophytes among them diospyros and reevesia which until now have not been identified from the eastern coast of north america most of the identified taxa belong to the extended multi layered broadleaved mesophytic forest that occupied the lowlands of the new jersey hinterland and reflects the zonal vegetation during time of deposition in higher altitudes or on edaphically drier slopes the mesophytic forest was replaced by conifer forest landscape changes probably induced the spread and diminution of several vegetation units during the late middle miocene an expansion of a conifer forest from 15 8 to 15 6 ma is probably connected to the appalachian uplift and a subsequent spreading of cupressaceae between 15 0 and 14 8 ma probably reflects a period of enhanced inundation of coastal lowlands the modern representatives of the main climatic elements among the encountered taxa are characterized by a typical temperate distribution climatic parameters mat cmmt wmmt map were calculated using bioclimatic analysis in light of the ongoing discussion concerning identifications of cupressaceae pollen grains two different variations of the bioclimatic analysis were performed both variations indicate humid warm temperate climatic conditions with mean annual temperatures of 13 c 5 c coldest month temperatures of 4 3 c 5 3 c and warmest month temperatures of 21 9 c 4 5 c annual precipitation values exceed 1000 mm for all samples both zonal vegetation and the calculated regional lowland palaeoclimate show no significant changes one factor creating generally climatically stable conditions between 15 8 and 12 7 ma was likely the buffering effect of the gulf current loop

airborne gravimetry of geohalo mission data processing and gravity field modeling airborne gravimetry is a crucial method to improve our knowledge about the earth gravity field especially in hard to access regions generally the accuracy of airborne gravimetry is several milligals which is suitable for filling the so called polar gaps in satellite derived global gravity field models here some investigations based on airborne gravity measurements from the geohalo mission over italy are presented to subtract the vertical accelerations from the values measured by the gravimeter four different versions of kinematic accelerations were derived from global navigation satellite systems gnss recordings to remove the high frequency noise a low pass filter with a cutoff wavelength of 200 s was applied to both chekan am measurements and kinematic accelerations from gnss to investigate how future airborne gravity campaigns could be designed a dedicated flight track was repeated two times showing that the equipment worked well also at higher altitude and speed from the final best results follows an rms of gravity differences at crossover points of 1 4 mgal which according to the law of error propagation implies the accuracy of a single measurement to be 1 4 2 1 mgal to demonstrate how a satellite only gravity field model can be improved by airborne measurements a gravity field model for the geohalo region has been computed to compute also an improved regional geoid model the point mass modeling pmm and the remove compute restore rcr technique using a recent satellite only model and residual terrain modeling rtm were applied finally gnss leveling points have been used to check the quality of the regional point mass model

the formation of caliche in soils of the mojave desert california abstract radiocarbon and 230th 234u dates of calcic horizons from calciorthid soil profiles in the mojave desert were used to calculate the rate of deposition of pedogenic caco3 a major period of caco3 deposition appears to have occurred about 20000 ybp forming calcic horizons below 100 cm depth during a climatic regime with greater effective rainfall than in the present the overall rate of deposition has been 1 0 to 3 5 g caco3 m2 yr during soil formation this rate is consistent with present day rates assuming that the atmospheric deposition of ca limits the process stable isotope ratios in calcic horizons indicate that caco3 precipitated from a soil environment with co2 of 15 5 13 c 12 c vs pdb and h2o of 2 0 18 o 16 o vs smow these values suggest that caco3 precipitates when seasonal drought simultaneously lowers soil pore pco2 and enriches soil water 18o by evaporation the role of soil calcic horizons in the global geochemical cycle of carbon is discussed

calibration of the climatic signal in a new pollen sequence from la grande pile a new core gpxx from la grande pile vosges france has enabled a more precise evaluation of pollen data concerning the last climatic cycle at this site and has enabled reconstruction of the monthly temperature and precipitation this paper shows that the various components of the reconstructed climatic signal are clearly separated and that they are coherent with the vegetation dynamics the eemian interglacial was influenced first by an oceanic climate and second by a more continental one the two interstadials st germain i and ii were mainly continental these three temperate periods ended with a cool and humid transition period dominated by boreal forests which may have been favourable to ice accretion the dansgaard oeschger oscillations from 55 to 25 kyr bp are not significantly recorded in la grande pile

microfaunal evidence for elevated pliocene temperatures in the arctic ocean the migration of thermophilic marine ostracoda into the arctic ocean during the pliocene indicates that winter and summer ocean temperatures around arctic margins were 0 c and 3 c respectively and that ice free conditions existed for most or all of the arctic by at least 3 5 3 0 ma probably earlier the opening of the bering strait allowed marine organisms to migrate through the arctic ocean mostly from the pacific ocean migrant taxa such as cythere hemicythere and neomonoceratina are known from pliocene deposits of alaska and canada as well as neogene deposits of the north pacific and atlantic oceans on the basis of ecological and zoogeographic information on ostracode species from more than 800 modern core top samples for the north atlantic north pacific and arctic oceans we determined winter and summer temperature tolerances for migrant taxa to be at or above about 0 c and 3 c this suggests ice free summers and probably a perennially ice free arctic ocean in some regions elevated water temperatures in the arctic ocean between 3 5 and 2 0 ma is supported by evidence for late pliocene increased meridional heat transport in the north atlantic ocean

seasonality intensification and long term winter cooling as a part of the late pliocene climate development abstract a mutual climatic range method is applied to the mediterranean marine pollen record of semaforo vrica section calabria italy covering the period from 2 46 ma to 2 11 ma the method yields detailed information on summer annual and winter temperatures and on precipitation during the nine obliquity and precession controlled glacial periods marine isotope stages 96 to 80 and eight interglacial periods marine isotope stages 95 to 81 characterising this time interval the reconstruction reveals higher temperatures of at least 2 8 c in mean annual and 2 2 c in winter temperatures and 500 mm in precipitation during the interglacials as compared to the present day climate in the study area during the glacials temperatures are generally lower as compared to the present day climate in the region but precipitation is equivalent along the consecutive interglacials a trend toward a reduction in annual and winter temperatures by more than 2 3 c and toward a higher seasonality is observed along the consecutive glacials a trend toward a strong reduction in all temperature parameters of at least 1 6 c is reconstructed climatic amplitudes of interglacial glacial transitions increase from the older to the younger cycles for summer and annual temperatures the cross spectral analyses suggest obliquity related warm humid cold dry interglacial glacial cycles which are superimposed by precession related warm dry cold humid cycles a time displacement in the development of temperatures and precipitation is indicated for the obliquity band by temperatures generally leading precipitation change at 4 kyr and on the precession band of 9 6 kyr in maximum

late pliocene variations of the mediterranean outflow late pliocene changes in the advection of mediterranean outflow water mow derivates were reconstructed at northeast atlantic dsdp odp sites 548 and 982 and compared to records of wmdw at west mediterranean site 978 neodymium isotope end values more positive than 10 5 11 reflect diluted mow derivates that spread almost continuously into the northeast atlantic from 3 7 to 2 55 ma reaching rockall plateau site 982 from 3 63 to 2 75 ma from 3 4 to 3 3 ma average mow temperature and salinity increased by 2 4 c and 1 psu both at proximal site 548 and distal site 982 the rise implies a rise in flow strength coeval with a long term rise in both west mediterranean sea surface salinity by almost 2 psu and average bottom water salinity bws by 1 psu despite inherent uncertainties in bws estimates the changes were linked with major mediterranean aridification and a drop in african monsoon humidity in contrast to model expectations the rise in mow salt discharge after 3 4 ma did not translate into improved ventilation of north atlantic deep water since it possibly was too small to significantly influence atlantic meridional overturning circulation right after 2 95 ma with the onset of major northern hemisphere glaciation long term average bottom water temperature bwt and bws at site 548 dropped abruptly by 5 c and 1 2 psu in contrast to more distal site 982 where bwt and bws continued to oscillate at estimates of 2 c and 1 5 2 5 psu higher than today until 2 6 ma we relate the small scale changes both to a reduced mow flow and to enhanced dilution by warmwaters of a strengthenednorth atlantic current temporarily replacingmowderivates at rockall plateau

quantification of climate and vegetation from southern african middle stone age sites an application using late pleistocene plant material from sibudu south africa abstract in southern africa numerous middle stone age msa sites document important steps in technological and behavioural development leading to significant changes in the lifeways of modern humans to assess whether these cultural changes and developments may be related to environmental changes we need to ascertain past environments to do this we apply a new quantitative method the gis based coexistence approach cagis on fossil plant material from the msa site sibudu kwazulu natal south africa previous qualitative environmental interpretations of the fossil fauna and flora of the site remain ambiguous because much of the material is anthropogenically introduced it is difficult to distinguish between the effects of natural changes in the local vegetation and behavioural changes of the people that inhabited the shelter cagis can be applied to such biased assemblages and seems to be an adequate method to directly quantify palaeoclimate and vegetation parameters at an archaeological site the cagis analysis shows that during the howiesons poort hp industry winters were slightly colder and drier than present whereas during summer temperatures and precipitation were similar to today post hp winters were drier and colder than present presumably colder than during the hp summer temperatures remained the same but summer precipitation decreased from the hp to post hp vegetation cover was less than today may be even less than during the hp the late msa was observably warmer than the older periods especially during winter at the same time summer precipitation slightly increased and vegetation became more dense but still remained generally open similar to today s anthropogenic landscape generally climatic changes are most pronouncedly reflected in winter temperature parameters especially in minimum winter temperatures and to a lesser extent by changes in summer precipitation the observed ecological trends seem to be affected mainly by variations through time in winter temperatures this refinement of interpretation was not discernible using previous methods for analysing the sibudu data

long chain alkenones in the early pliocene sicilian sediments trubi formation punta di maiata section implications for the alkenone paleothermometry abstract article history received 6 september 2010received in revised form 15 march 2011accepted 16 march 2011available online 23 march 2011keywords alkenoneearly pliocenereticulofenestridsmediterranean seasea surface temperature the u k 37 record and coccolithophorid remains in sediments from the early pliocene sicilian trubi formation punta di maiata have been estimated to assess the possible in uence of changes in the alkenone producingcoccolithophoridsontheu k 37 temperaturerelationship thesamplesweredominatedbysmallreticulofenestra r minutaandr minutula andthec 37 andc 38 methylandethylunsaturationratios u k 37 u k38me andu k38et weresimilar to those found in modern populations e huxleyi and g oceanica those results suggest that the earlypliocene small reticulofenetrids had a similar temperature sensitivity of u k 37 to thatfound in present day theseresults support the application of the u k 37 modern calibrations to reconstruct sst at least back in the pliocene 2011 published by elsevier b v

pliocene paleoclimatic reconstruction using dinoflagellate cysts comparison of methods the application of quantitative and semiquantitative methods to assemblage data from dinoflagellate cysts shows potential for interpreting past environments both in terms of paleotemperature estimates and in recognizing water masses and circulation patterns estimates of winter sea surface temperature wsst were produced by using the impagidinium index ii method and by applying a winter temperature transfer function tfw estimates of summer sea surface temperature ssst were produced by using a summer temperature transfer function tfs two methods based on a temperature distribution chart act and actpo and a method based on the ratio of gonyaulacoid protoperidinioid specimens g p wsst estimates from the ii and tfw methods are in close agreement except where impagidinium species are sparse ssst estimates from tfs are more variable the value of the g p ratio for the pliocene data in this paper is limited by the apparent sparsity of protoperidinioids which results in monotonous ssst estimates of 14 26 c the act methods show two biases for the pliocene data set taxonomic substitution may force matches yielding incorrect temperature estimates and the method is highly sensitive to the end points of species distributions dinocyst assemblage data were applied to reconstruct pliocene sea surface temperatures between 3 5 2 5 ma from dsdp hole 552a and odp holes 646b and 642b which are presently located beneath cold and cool temperate waters north of 56 n our initial results suggest that at 3 0 ma wssts were a few degrees c warmer than the present and that there was a somewhat reduced north south temperature gradient for all three sites it is likely that sssts were also warmer but by an unknown perhaps large amount past oceanic circulation in the north atlantic was probably different from the present

the coexistence approach theoretical background and practical considerations of using plant fossils for climate quantification the coexistence approach was established by mosbrugger and utescher 1997 as a plant based method to reconstruct palaeoclimate by considering recent climatic distribution ranges of the nearest living relatives of each fossil taxon during its existence for over more than 15 years its basics have been tested and reviewed in comparison with other terrestrial and marine climate reconstruction techniques and climate modelling data however some controversies remain about its underlying data or its applicability in general in view of these controversies this paper discusses the power and limitations of the coexistence approach by summarising past results and new developments we give insights into the details and problems of each step of the application from the assignment of the fossil plant to the most suitable nearest living relative the crucial consideration of the usefulness of specific taxa towards their climatic values and the correct interpretation of the software based suggested palaeoclimatic intervals furthermore we reflect on the fundamental data integrated in the coexistence approach by explaining different concepts and usages of plant distribution information and the advantages and disadvantages of modern climatic maps additionally we elaborate on the importance of continually updating the information incorporated in the database due to new findings in e g palaeo botany meteorology and computer technology finally for a transparent and appropriate use we give certain guidelines for future applications and emphasize to users how to carefully consider and discuss their results we show the coexistence approach to be an adaptive method capable of yielding palaeoclimatic and palaeoenvironmental information through rime and space c 2014 elsevier b v all rights reserved

global middle pliocene biome reconstruction a data model synthesis 1 the middle pliocene warm interval ca 3 ma bp has been extensively studied however our knowledge concerning the global distribution of middle pliocene biomes remains far from complete this paper presents the results from a first attempt at simulating the distribution of different mid pliocene biomes using an advanced numerical general circulation climate model hadley centre atmospheric model version 3 and the biome 4 vegetation model the modeling indicates that during the middle pliocene the geographical coverage of tundra type biomes may have been significantly reduced compared with the present day in the northern hemisphere high latitude forests expand in the place of tundra forms of vegetation total area covered by forest increases for the pliocene case compared with the present day arid deserts become less prevalent in the pliocene scenario and are replaced by tropical xerophytic shrublands and savanna type vegetation these results compare favorably with geological data in general and with the u s geological survey s prism2 middle pliocene vegetation reconstruction although data model inconsistencies are apparent although some of these inconsistencies relate to the weaknesses of the climate and biome model employed others identify deficiencies in the extant geological data set or the interpretation of this data this modeled biome reconstruction will serve as a useful vehicle for aiding in future comparisons between geological data on middle pliocene biomes and model predictions

geographic and temporal patterns in the late neogene 12 3 ma aridification of europe the use of small mammals as paleoprecipitation proxies abstract present day relations between small mammal community structure and rainfall are used to predict late neogene 12 3 ma precipitation patterns in europe and anatolia new proxy methods are developed which include regressions of mean annual and minimum monthly precipitation on diet invertivory index and locomotion habitat arboreality index a series of precipitation maps and a set of regional precipitation curves through time at 1 myr resolution are presented precipitation curves at a higher temporal resolution are constructed for the region of central spain the miocene results show the existence between 12 and 9 ma of a large wet 800 1200 mm yr zone extending from northern spain to the ukraine and characterized by the whole year penetration of large amounts of moisture far into the continent between 10 9 and 5 ma this european temperate wet zone etwz shrinks and or moves northward resulting in diachronous aridification a coeval northward migration of the subtropical high pressure zone shpz is hypothesized which is also consistent with the predicted onset of seasonal summer dryness between 10 and 8 ma the maximum extension of the etwz at 12 9 ma temporally correlates with northern hemisphere cooling suggesting that climate zonation rather than the global amount of atmospheric moisture controlled european climate at this time the main aridification at 9 8 ma could best be explained by a northward extension shifting of the subtropical high pressure zone and a transition towards less zonal circulation processes which ultimately could have been triggered by uplift of the tibetan plateau a temporary increase of precipitation at 7 6 ma is associated with renewed global cooling the lowest precipitation values less than 400 mm yr occur during the pliocene in southern and eastern europe uplift in eastern europe carpathians shrinking of the paratethys could well explain the aridification in this area and the associated sharpening of east west precipitation gradients across the continent

micropaleontological evidence for increased meridional heat transport in the north atlantic ocean during the pliocene the middle pliocene approximately 3 million years ago has been identified as the last time the earth was significantly warmer than it was during the last interglacial and holocene a quantitative micropaleontological paleotemperature transect from equator to high latitudes in the north atlantic indicates that middle pliocene warmth involved increased meridional oceanic heat transport

late oligocene and miocene climate and vegetation in the eastern paratethys area northeast bulgaria based on pollen data abstract the results of palynological studies of the oligo miocene in the western part of the euxinian basin eastern paratethys are based on the analysis of 57 samples from core c 136a drilled near the town of balchik varna district some samples were barren or contained very little pollen and were not included in the analysis quantitative data are thus confined to 26 polleniferous samples we present results for the upper oligocene as well as the tarkhanian karaganian bessarabian and chersonian stages of the middle to upper miocene mixed deciduous forests were widespread during the time period studied swamp forests are also recorded with distribution maxima observed in the oligocene and in the bessarabian the widest extent of herbaceous vegetation is recorded in the late bessarabian and chersonian when it occupied open landscapes after a marine regressional phase the climatic data reconstructed by the coexistence approach indicate mean annual temperatures mats of ca 15 17 c and mean annual precipitation maps of 800 1300 mm for the upper oligocene the narrowest coexistence intervals of the tarkhanian and karaganian display mats of 14 17 c and maps of 800 1300 mm the most substantial data are for the bessarabian in which the lower part is characterized by mats of 15 6 16 6 c and maps from 800 1200 1300 mm the results for the upper part of the bessarabian are more variable especially with respect to precipitation that is generally lower 700 800 mm the same is true for the chersonian where besides lower precipitation lower annual temperature and temperature of coldest month are observed these results correlate with previous vegetation and palaeoclimate data from the forecarpathian basin nw bulgaria

vegetation response to obliquity and precession forcing during the mid pleistocene transition in western mediterranean region odp site 976 abstract the odp leg 161 site 976 alboran sea is a deep sea section sampled at a water depth of 1108 m in the western mediterranean sea pollen analysis provides a vegetation and climate record of the mid pleistocene transition mpt roughly one million years ago the age model tied to biostratigraphic events was revised by aligning the pollen climate index pci to mediterranean kc01b and global lr04 oxygen isotope records the studied time slice spans the interval 1 09 ma mis 31 to 0 90 ma mis 23 across this interval past phytogeography of nowadays extinct taxa which were rare allows a successful application of the modern analogues technique mat to quantitative climate reconstructions for the mpt five long term obliquity related vegetation successions o1 to o5 and eight short term precession related vegetation successions p1 to p8 are observed within the studied interval these vegetation successions regardless of their duration show the same pattern the progressive replacement of temperate trees by mountainous taxa and then by herbs and steppe maxima precession related successions correspond therefore to as dramatic vegetation changes as those driven by obliquity including a final steppe phase under deteriorated climate conditions wavelet analysis of the pci record shows that the western mediterranean experienced a shift at 1 01 ma from precession dominated frequencies 1 05 1 01 ma to obliquity dominated frequencies 1 01 0 9 ma there is therefore an apparent discrepancy between wavelet analysis results and vegetation dynamic analysis which suggests that obliquity and precession are recorded throughout the entire studied interval this discrepancy could result from the fact that the pci record sums somehow similar vegetation changes wet to dry occurring at different periodicities such a complex vegetation dynamics is mathematically rendered through a single parameter i e principal component which does not successfully catch the subtle combinations of variability occurring at two close periodicities furthermore the pollen inferred early pleistocene vegetation dynamic and climate of the western mediterranean region does not show a decrease of the obliquity response relative to the precession response at the onset of the mpt

cenozoic continental climatic evolution of central europe continental climate evolution of central europe has been reconstructed quantitatively for the last 45 million years providing inferred data on mean annual temperature and precipitation and winter and summer temperatures although some regional effects occur the european cenozoic continental climate record correlates well with the global oxygen isotope record from marine environments during the last 45 million years continental cooling is especially pronounced for inferred winter temperatures but hardly observable from summer temperatures correspondingly cenozoic cooling in central europe is directly associated with an increase of seasonality in contrast inferred cenozoic mean annual precipitation remained relatively stable indicating the importance of latent heat transport throughout the cenozoic moreover our data support the concept that changes in atmospheric co2 concentrations although linked to climate changes were not the major driving force of cenozoic cooling

a method for climatic reconstruction of the mediterranean pliocene using pollen data pollen data from numerous sites around the mediterranean sea indicate that several important vegetation and climatic changes occurred during the pliocene these data are in good agreement with pollen records from northwest europe and with 18o curves from mediterranean and atlantic deep sea cores quantitative palaeoclimatic reconstructions from pliocene pollen data of the mediterranean region cannot be based on conventional modern analogue techniques as individual pliocene pollen spectra contain taxa representing temperate warm temperate and subtropical plants that do not grow together today instead we propose a new method that uses a climatic amplitude method modified to take partially into account the relative abundances of the taxa we applied this method to the pliocene garraf 1 palynological sequence from catalonia which provides a long continuous record of climatic change from 5 3 ma to the early pleistocene we estimate that annual temperatures were 1 to 5 c higher than today and the annual precipitation 400 to 1000 mm higher than today prior to the beginning of the late cenozoic glacial interglacial cycles in contrast temperature and precipitation both fell sharply during the glacial phases of the earliest glacial interglacial cycles

quantification of climate change for the last 20 000 years from wonderkrater south africa implications for the long term dynamics of the intertropical convergence zone abstract in southeast africa a region for which few palaeoenvironmental records are available the fossil pollen record from the wonderkrater spring mound has contributed substantially to our understanding of past vegetation change since the last glacial maximum lgm 21 ka multivariate analysis of the pollen data by scott and thackeray 1987 provided environmental reconstructions suggesting relatively mesic lgm conditions with warm and dry conditions during the early holocene 11 6 cal kbp this conforms to predicted patterns of precipitation change in the southern african tropics in response to northern hemisphere cooling and orbital forcing subsequent data from the cold air cave speleothems and a sea surface temperature record from the mozambique channel however indicate that conditions during the early to mid holocene may have been wetter than present in the wonderkrater region to explore this question further we have created a series of botanical climatological transfer functions based on a combination of modern climate and plant distribution data from southern africa applying these to the wonderkrater fossil pollen sequence we have derived quantitative estimates for temperatures during the cold and warm quarters as well as precipitation during the wet and dry quarters in addition a species selection method based on bayesian statistics is outlined which provided a parsimonious choice of likely plant species from what are otherwise taxonomically broad pollen types we do not propose that our findings invalidate the previous principal component analyses but they do have the advantage of being based more clearly on the relationship between modern plant distributions and individual climatic variables results indicate that temperatures during both the warm and cold seasons were 6 2 c colder during the lgm and younger dryas and that rainy season precipitation during the last glacial maximum was 50 of that during the mid holocene our results also imply that changes in precipitation at wonderkrater generally track changes in mozambique channel sea surface temperatures with a steady increase following the younger dryas to a period of maximum water availability at wonderkrater 3 7 ka these findings argue against a dominant role of a shifting intertropical convergence zone in determining long term environmental trends and indicate that the northern and southern tropics experienced similar climatic trends during the last 20 kyr

tectonic control on the late stage exhumation of the aar massif switzerland constraints from apatite fission track and u th he data 1 we examine the hypothesis that pliocene exhumation of the external massifs in the central alps is controlled by climatic change new thermochronological data from the western gastern aar massif are used to investigate the timing extent and reasons for neogene exhumation our data reveal that exhumation was constant with 0 5 km ma over the last 10 ma in the north in the southern part exhumation was of the same order until 3 5 ma but then increased gradually toward the south to values of up to 1 2 km ma resulting in overall northward tilting of the western aar massif we explain this accelerated exhumation in the south after 3 5 ma mainly by tectonic denudation in the footwall of the rhone simplon fault and discuss changes in deep crustal configuration which may have triggered south directed normal faulting we propose that the rhone river was structurally trapped by the rhone simplon normal fault zone which additionally enhanced erosion in the southern section of the aar massif climatic forcing may have an impact in the very late stage of exhumation due to alpine glaciation in the late pliocene

how much did climate force the messinian salinity crisis quantified climatic conditions from pollen records in the mediterranean region the latest miocene 5 96 to 5 33 ma is characterised by an outstanding event the desiccation of the mediterranean sea messinian salinity crisis it has been suggested that this was caused by a tectonic event with no climatic change playing a role in desiccation quantifying the climate of the region during this period will help support or refute this hypothesis an effective method for reconstructing the climate from neogene pollen data is the climatic amplitude method based on the modern climatic requirements of plants to interpret fossil data it has been conceived especially for periods devoid of modern vegetation analogue twenty messinian to lower zanclean pollen sequences are now available in the peri mediterranean region most of them do not cover the whole messinian interval particularly those along the mediterranean shorelines where sedimentation was interrupted during the sea s desiccation in contrast sedimentation was almost continuous in such areas as the atlantic side of morocco along the adriatic coast including the po valley and to a lesser extent the black sea the mediterranean sites nonetheless provide a reliable if not a discontinuous record of vegetation variability in time and space a first examination of the pollen diagrams reveals a high regional variability controlled by local conditions and throughout the interval a southward increase in herb pollen frequency in contrast to the tree pollen frequency this indicates that open and probably dry environments existed in the southern mediterranean region prior to during and after the salinity crisis trees developed in areas close to mountains such as in the po valley in cerdanya and in the black sea region most variations observed in the pollen diagrams are constrained by fluctuations of pinus pollen amounts indicating eustatic variations climatic quantification from pollen data does not show obvious climatic changes due to the desiccation of the mediterranean sea especially in the dry and warm southwestern mediterranean area sicily southern spain and north africa at maccarone along the adriatic sea a decrease in temperatures of the coldest month and less importantly a decrease in mean annual temperatures corresponding to a drastic vegetation change are reconstructed these temperature variations are assumed to be controlled by regional environmental changes massive arrival of waters in this basin rather than to reflect cooling because some authors link the second phase of evaporite deposition to a period of global warming some migrations of plants probably occurred as a response to mediterranean desiccation but the climatic contrast which has probably existed at that time between the central mediterranean and the peripheral areas might be amplified climatic reconstruction from pollen data in the western mediterranean area shows that climate is not the direct cause of the mediterranean desiccation as the mediterranean region had experienced continuously high evaporation long before the crisis therefore the main factor leading to this event seems to be the successive closures of the betic and rifian corridors isolating the mediterranean sea from the atlantic ocean

pollen and macrofossil analyses of pliocene lacustrine sediments salto river valley central italy abstract the study of two sedimentary records sampled in the fluvio lacustrine succession of high salto river valley rieti central italy was originated in the frame of the geomorphologic map of italy apat 2008 field survey and improved with a multidisciplinary approach addressed to a better knowledge of the plio pleistocene continental environments of central apennines the two successions are associated to different sedimentary facies with lateral heteropic relations the deposits cropping out at marano de marsi are thought to represent deposition in the distal portion of a lacustrine delta while those of borgorose took place in a frankly lacustrine environment the sediment succession from marano de marsi 11 m was sampled from an outcrop the one from borgorose 24 5 m from a drillhole palaeomagnetic investigations carried out on both sediment records indicate a normal magnetic polarity and very low magnetic susceptibility values in the record from marano de marsi section gymnosperm pollen is prevailing four main and short angiosperm arboreal pollen oscillations can however be observed the oldest of which more marked the gymnosperms are mainly represented by pinus haploxylon type pinus sylvestris type cedrus picea abies cathaya tsuga taxodium type among angiosperms the dominant taxa some of which at present extinct in italy are quercus zelkova ulmus carya and pterocarya the presence of pollen of subtropical taxa as nyssa cfr rhoiptelea liquidambar engelhardia is worth to be mentioned the investigation was integrated also by a preliminary study of macrofossils fossil impressions with some organic matter of angiosperm and gymnosperm leaves and seeds fruits were ascribed to acer cfr monspessulanum carpinus cfr orientalis engelhardia fagus hedera liquidambar quercus rosa abies and pinus the 24 5 m long sediment core from borgorose resulted very poor in pollen with the same list of arboreal taxa at present extinct in italy found at marano de marsi and a diagram was drawn only for the stretch of the core between 3 and 8 2 m gymnosperms p haploxylon type is dominant and accompanied by p sylvestris type picea taxodium type cedrus and tsuga are always prevailing the results obtained by this interdisciplinary investigation indicate that marano de marsi and borgorose successions can be possibly attributed to the upper pliocene normal polarity olduvai subchron even if an older age considering the present state of the art on pliocene continental records and the peculiarity of the site and of the region cannot be excluded

establishing constraints on groundwater ages with 36cl 14c 3h and noble gases a case study in the eastern paris basin france abstract groundwaters from the tithonian kimmeridgian oxfordian and upper dogger aquifers within the eastern part of the paris basin france were characterised using 3 h 14 c and 36 cl and noble gases tracers to evaluate their residence times and determine their recharge period this information is an important prerequisite to evaluating the confinement properties of the callovo oxfordian clay formation sandwiched between the oxfordian aquifer and the dogger aquifer currently being investigated by the french nuclear waste management agency andra for radioactive waste disposal data presented in this paper are used to test 4 hypotheses 1 the oxfordian limestone is isolated from the overlying tithonian kimmeridgian surface aquifer this first hypothesis is supported by the presence of measurable 3 h activities in groundwaters from the surface aquifer 6 11 tu and by its absence in groundwaters derived from deeper aquifers 2 the callovo oxfordian clay sequence in the vicinity of the url serves as an effective barrier to advective flow and transport between the underlying upper dogger aquifer and the overlying oxfordian limestone aquifer this second hypothesis is supported by relatively low concentrations of cl 3 5 78 mg l 1 na 15 145 mg l 1 br 0 08 0 4 mg l 1 and 4 he rad 0 2 2 3 ccstp g 1 and slightly higher 36 cl cl ratios 2 7 59 10 15 at at 1 in groundwaters from the oxfordian aquifer compared to those from the upper dogger aquifer 345 4027 mgcl l 1 402 2390 mgna l 1 1 8 22 2 mgbr l 1 1 6 37 2 ccstp he g 1 1 5 10 15 at 36 cl at 1 cl 3 groundwaters from the oxfordian aquifer in the vicinity of url are pre holocene with residence times exceeding 10 ka geochemical and isotopic lines of evidence for this hypothesis include a 13 c values measured on oxfordian aquifer waters that are close to 13 c of the aquifer matrix reflecting strong isotopic exchange over several thousand years b noble gas temperatures that indicate recharge temperatures between 3 and 8 6 c lower by 2 7 c than the modern average temperature in this area c radiogenic 4 he concentrations between 0 16 10 5 and 2 3 10 5 ccstp g 1 of water about 2 3 orders of magnitude greater than the 4 he concentration of air equilibrated water 4 groundwater residence time for the upper dogger aquifer in the vicinity of the url probably exceed several hundred thousand years such long residence times are indicated by the accumulation of radiogenic he up to 37 10 5 ccstp g 1 assuming a closed system primary contributors to uncertainties in interpretation of the data presented in this paper are the lack of well defined 36 cl cl input ratio knowledge about the 4 he rad sources for oxfordian and dogger aquifers knowledge about transport processes occurring through the dogger aquifer and the extensive dilution of initial 14 c activities by dissolution exchange with aquifer matrix overall however although the data presented in this paper remain semi quantitative due to inevitable intrinsic limitations of the methods none contradict the hypotheses of long residence times and aquifer isolation in the vicinity of the url

impact of short term climatic events on latest pliocene land settings and communities in central italy upper valdarno basin abstract the upper valdarno italy plio pleistocene continental deposits record the latest uniform subtropical humid conditions and the successive climatic signature of glacial interglacial cycling the palynological and sedimentological analyses on the poggio rosso alluvial plain sediments reveal two major climatic fluctuations correlated to a glacial interglacial cycle just before the plio pleistocene boundary the glacial phase indicated by the expansion of herbs as well as by ephemeral streams associated with calcareous palaeosols extends from the base of the succession and culminates close to an impressive mammalian bone accumulation dated at 1 87 ma the associated increasing aridity had severe consequences on the faunal communities inducing the migration of open plain dwellers and the trapping of other residents around a few residual shrinking water bodies a cooperative pachycrocuta brevirostris clan acted as regulator of game populations debilitated by drought previous research indicates that hyenas were also the major bone accumulators the following moister and warmer interglacial phase ca 1 83 ma is documented by arboreal taxa and hydromorphic palaeosols in a floodplain crossed by migrating perennial sinuous streams the climatic amplitude method calculated mean annual temperatures around 12 5 14 c and mean annual precipitation around 800 mm with a minimum of 400 mm during the glacial phase and 15 16 19 c and 750 1200 mm during the interglacial phase the reconstruction reveals higher mean annual temperatures and precipitation during the interglacial as compared to the present day climate during the glacial conditions were similar to today s in all but lower precipitation values were reached during the acme drought phase just above the fossiliferous bed poggio rosso documents the ecological consequences the buildup of the apennine chain had under the effects of the latest pliocene global climatic changes it therefore represents one of the first signals of the patchiness that since then gradually increased leading to the eventual habitat fragmentation typical of the late pleistocene landscapes

late neogene erosion of the alps a climate driver as with many mountain belts globally the alps have seen a large increase in sediment yield in the late neogene the hypothesis that this increase results from climate change impacts on erosion rate over the past 5 ma is testable given the extensive work completed in the alps sediment budgets thermochronology based cooling rates and estimates of modern rock uplift and erosion in the western alps are reviewed to search for correlation in space and time that might fingerprint climatic events major increases in sediment yield are apparent starting in the late messinian 5 5 mya and accelerating toward the present day this suggests the occurrence of a series of climatic changes that increased erosion rates even as tectonic processes appear to have slowed or stopped at present tight correlations in time are difficult to establish and there remain open questions about the role of tectonics in the coupled system

modeling pliocene warmth modeling studies relevant to the question of pliocene warmth are reviewed although significant regional climate variations may be due to pliocene changes in orography and ocean circulation these changes do not appear sufficient to explain inferred globally increased warmth climate modeling studies for a doubling of co2 suggest high latitude temperature increases approximately comparable to inferred warming during the pliocene i suggest that such a co2 increase may be primarily responsible for the pliocene temperature increase downdraw of co2 since the pliocene is consistent with some geochemical indications of enhanced weathering in the pleistocene however additional proxy testing of this hypothesis is required the co2 models also predict tropical sea surface warming of 2 3 c and winter temperature warming in central eurasia 50 70 n of 4 10 c predictions that distinguish co2 from some other mechanisms enhanced scrutiny of pliocene records from the above regions may prove a valuable test of the co2 hypothesis finally although a co2 increase may be responsible for pliocene warmth this time interval should not be cited as a direct analog for a future greenhouse warming as the future climate will have a significant nonequilibrium response because of the rapid rate of change of forcing despite these limitations enhanced study of pliocene climates may be very valuable as an independent source of validation of co2 doubling simulations

aeolian construction and alluvial dismantling of a fault bounded intracontinental aeolian dune field teruel basin spain a continental perspective on late pliocene climate change and variability an aeolian dune field migrating to the east encroached on the toes of alluvial fans in the teruel basin eastern spain during a short interval in the late pliocene ca 2 9 to 2 6 ma when northern hemisphere glaciation and strong glacial interglacial cycles began preservation of the dune field was controlled by syn sedimentary activity of a normal fault ephemeral water discharge eroded aeolian sands and formed v shaped channels in which aeolian sandstone blocks accumulated the incorporation of loose aeolian sand in wadi waters modified the sediment water ratio changing the physical properties of the flows as they penetrated the aeolian dune field the erosion and cover of aeolian dune foresets by sheetflood deposits suggest that dune damming caused the intermittent ponding of water behind the dunes and its flashy release the arid climate in the late pliocene western mediterranean realm favoured the transport of windblown sediments from northern africa and western mediterranean land masses into the mediterranean the formation of the studied aeolian dune field 2 9 to 2 6 ma and possibly others for example the atacama namib and sahara deserts correlates with a strong increase of the influence of obliquity which can be attributed to the combination of a regional expression related to the reduced effect of precession due to a minimum in the long period 2 3 ma eccentricity cycle and a remote expression of the onset of the northern hemisphere glaciation

the messinian salinity crisis in the dardanelles region chronostratigraphic constraints abstract an intense controversy on chronostratigraphy of upper miocene lower pliocene deposits and the messinian salinity crisis in the dardanelles area led to a systematic investigation of calcareous nannoplankton content of 10 key sections representative of the most relevant regional kirazli and alcitepe formations our study shows clearly that the kirazli formation deposits predate the messinian salinity crisis while those of the alcitepe formation postdate this outstanding event which severely impacted the region as widely known around the mediterranean basin fluvial canyon cutting or gap in sedimentation linked to the peak of the messinian salinity crisis separates the two formations detailed palaeoenvironmental investigations based on the fluctuation and distribution pattern of dinoflagellate cysts pollen grains and calcareous nannoplankton allow us to reconstruct the regional palaeogeography before during and after the messinian salinity crisis the gathered data do not indicate any marine corridor between the eastern mediterranean sea and eastern paratethys through the marmara sea region at the time of the messinian salinity crisis

intensive kaolinization during a lateritic weathering event in south west spain mineralogical and geochemical inferences from a relict paleosol abstract this study documents the mineralogical and geochemical record of a lateritic weathering event during the pliocene in south west spain the paleoweathering profile derived from arkosic sands and comprises a white sandy clayey saprolite a red mottled clay zone overlain by a thick soft layer and a ferruginous pisolitic hardcap partially dismantled by erosive processes kaolinite quartz and degraded k feldspars are the major minerals forming the saprolite along with al goethite mottled zone as well as gibbsite and boehmite soft layer while the pisolitic duricrust is essentially composed of quartz grains embedded in a matrix of fe oxy hydroxides hematite goethite and or maghemite besides quartz the phases most resistant to alteration were a variety of heavy minerals mostly titanium oxides that are present as minor impurities in the residual kaolin deposit the dominant weathering process of kaolinization is geochemically characterized by striking losses of na k ca mg and large ion lithophile elements rb sr cs ba and u because of the almost entirely breakdown of primary minerals mainly feldspars and 2 1 phyllosilicates the ti normalized distribution patterns of trace elements also reveals remobilization and redistribution processes within the profile involving high field strength elements classically regarded as immobile like zr and hf iron showed a contrasted behaviour with depletion in the saprolite zone and strong accumulation in the pisolitic duricrust various transition trace metals cr v sc th nb and ta remained relatively immobile during the weathering and were residually concentrated in the duricrust linked to the fe oxy hydroxides the geochemical and mineralogical evolution of the paleosol studied is consistent with a laterization process evolved under humid subtropical conditions and driven by morphodynamic and hydrodynamic factors gently sloping coastal area with fluctuating water table and rapid water percolation favourable for the development of a deeply kaolinized paleosurface

new taphonomic data of the 1 myr hominin butchery at untermassfeld thuringia germany abstract untermassfeld has provided a butchered bone assemblage and a mode 1 lithic record demonstrating hominin presence at a site which was classically viewed as paleontological this archaeological record was found during fieldwork and surveying in fluvial river banks and low to medium energy channel erosion sediments paleomagnetism and biostratigraphy has yielded an age for this hominin occupation close to the onset of the jaramillo subchron ca 1 07 myr in this paper we present new taphonomic data of the cut marked and hammer related bone material corresponding mainly to large sized herd species i e bison but also from cervids eucladoceros giulii and cervus s l nestii vallonnetensis and megafaunal species i e stephanorhinus hundsheimensis and hippopotamus amphibius antiquus distribution of skeletal elements and bone surface features suggests that this bone assemblage consists of animal remains with different taphonomic origins the assemblage formed during at most two or three sediment laden floods transporting both lithic tools and remains of animals that died of natural causes or were killed by predators the new taphonomic results presented here are important to analyze hominin colonization and adaptation to european mid latitude environments at 1 myr in competition for meat resources with large carnivores i e pachycrocuta brevirostris and panthera onca gombaszoegensis

middle miocene latitudinal climatic gradient in western europe evidence from pollen records abstract pollen analysis of sections spanning the middle miocene langhian and serravallian from southern spain to switzerland has been carried out with the aim of reconstructing the existing latitudinal environmental gradient floral assemblages indicate a tropical subtropical to warm temperate climate for the entire area during the middle miocene the presence in all pollen spectra of taxa with high temperature requirements demonstrates that the latitudinal gradient in temperature was relatively low the development of a diverse subarid flora in southern spain including neurada lygeum prosopis calligonum nitraria caesalpiniaceae etc points to a very dry climate with a marked seasonality these features clearly indicate that a very warm and dry climate i e a steppe environment was already present during the langhian in the northwestern mediterranean area on the other hand milder conditions are progressively inferred towards the north as subdesertic elements gradually disappeared and taxa with higher water requirements increased the latter dominates the pollen assemblages in the eastern central part of france and switzerland thus precipitations would have been evenly distributed throughout the year we interpret this gradient from subdesertic vegetation in the south to humidity adapted plant environments in the north as the result of a latitudinal gradient in precipitation