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The environment of the Marseille basin in the Early Pleistocene was reconstructed through a multiproxy study of fluvial tufa deposits. Palaeomagnetic measurements revealed the Jaramillo subchron and dated the tufa to within the 0.8–1.5 Ma interval, probably between 0.9 and1.2 Ma. Sedimentological studies show varied depositional environments comprising natural dams formed by accumulations of plants promoting the development of upstream water bodies. The very negative δ13C values indicate that the Marseille tufa is not travertine sensu stricto but tufa deposited by local cold-water rivers. Palynological analyses indicate a semi-forested, diverse, mosaic vegetation landscape dominated by a Mediterranean pine and oak forest. Along the streams, the riparian forest was diverse and included Juglans, Castanea, Platanus and Vitis. The potential diet reconstructed from pollen was varied. The most surprising discovery was the presence of proto-cereals, which could potentially enrich the diet with carbohydrates. The identification of spores of coprophilous fungi seems to indicate the presence in situ of large herbivore herds. It is possible that, as in Anatolia, the disturbance of ecosystems by large herbivores was responsible for the genetic mutation of Poaceae and the appearance of proto-cereals. Climatic reconstructions indicate a slightly cooler and wetter climate than the present.

The Early-Late Pliocene transition (â¼ 3.6 Ma) is a key period for understanding future climate change linked to increases in greenhouse gases. Around the Western Mediterranean Basin, the Early-Late Pliocene transition was marked by the establishment of a Mediterranean climate with summer droughts, cool/wet winters and latitudinal gradients. However, environmental changes in the eastern part of the Mediterranean area during the Early-Late Pliocene transition have rarely been documented. Here, we propose to reconstruct the environmental and climate changes during the Early-Late Pliocene transition from the Burdur Basin sequence, located in Southwestern Türkiye. This study aims to (1) characterize vegetation patterns, lake dynamics, and water level fluctuations using pollen and Non-Pollen Palynomorph (NPP) proxies, and (2) examine the morphological features of large Poaceae pollen grains (Cerealia-type). We also aim to quantitatively reconstruct climate changes through a multi-method approach, including the Modern Analogue Technique, Weighted Averaging Partial Least Squares regression, Random Forest, and Boosted Regression Trees and the Climatic Amplitude Method.

The Early-Late Pliocene transition (∼ 3.6 Ma) is a key period for understanding future climate change linked to increases in greenhouse gases. Around the Western Mediterranean Basin, the Early-Late Pliocene transition was marked by the establishment of a Mediterranean climate with summer droughts, cool/wet winters and latitudinal gradients. However, environmental changes in the eastern part of the Mediterranean area during the Early-Late Pliocene transition have rarely been documented. Here, we propose to reconstruct the environmental and climate changes during the Early-Late Pliocene transition from the Burdur Basin sequence, located in Southwestern Türkiye. This study aims to (1) characterize vegetation patterns, lake dynamics, and water level fluctuations using pollen and Non-Pollen Palynomorph (NPP) proxies, and (2) examine the morphological features of large Poaceae pollen grains (Cerealia-type). We also aim to quantitatively reconstruct climate changes through a multi-method approach, including the Modern Analogue Technique, Weighted Averaging Partial Least Squares regression, Random Forest, and Boosted Regression Trees and the Climatic Amplitude Method. The results indicate that, during the Early-Late Pliocene transition at Burdur, the vegetation was dominated by steppes with Poaceae, Artemisia, and Amaranthaceae. Subsequently, arboreal taxa decreased and an alternation between steppe grasslands with deciduous Quercus and steppes dominated by Amaranthaceae became evident. The lacustrine ecosystem was characterized by semi-aquatic vegetation and freshwater algae, exhibiting alternating oligotrophic and eutrophic conditions. Large Poaceae pollen grains (Cerealia-type) are recorded in the Burdur Basin sequence, but their percentages are lower than those at Acıgöl to the west, a nearby record dated to the Pleistocene. The morphological characteristics of these large Poaceae pollen grains from Burdur are similar to those of domesticated cereals from recent periods, preventing a clear distinction between wild and domesticated Poaceae pollen. Pollen-inferred climate reconstructions show similar trends across the five methods, with reconstructed values during the Early-Late transition being close to present-day values at Burdur region. Following a climatic optimum in precipitation and temperature during the Early Pliocene, our results indicate an alternation between cool/wet conditions and warmer/drier conditions during the Late Pliocene in Southwestern Anatolia. Around the Mediterranean Basin, records show that the Early Pliocene had warmer conditions compared to modern values and wetter conditions, with a north (wetter)-south (drier) gradient in terms of precipitation. The Late Pliocene is characterized by colder and more humid conditions in the Western Mediterranean, while the Eastern Mediterranean (Southwestern Türkiye) and Central Asia experienced more arid conditions. A weak Atlantic Meridional Overturning Circulation (AMOC) is identified in Europe during the Late Pliocene, leading to cooler and wetter conditions primarily in the Northwestern Mediterranean. While model simulations of PlioMIP2 show warmer conditions and a latitudinally contrasted precipitation pattern, with wetter conditions in Northern Europe and drier conditions in the south during the mid-Pliocene Warm Period (3.264–3.025 Ma).

Climate evolution of the Mediterranean region during the Holocene exhibits strong spatial and temporal variability, which is notoriously difficult for models to reproduce. We propose here a new proxy-based climate synthesis synthesis and its comparison – at a regional (∼ 100 km) level – with a regional climate model to examine (i) opposing northern and southern precipitation regimes and (ii) an east-to-west precipitation dipole during the Holocene across the Mediterranean basin. Using precipitation estimates inferred from marine and terrestrial pollen archives, we focus on the early to mid-Holocene (8000 to 6000 cal yr BP) and the late Holocene (4000 to 2000 cal yr BP), to test these hypotheses on a Mediterranean-wide scale. Special attention was given to the reconstruction of season-specific climate information, notably summer and winter precipitation. The reconstructed climatic trends corroborate the north–south partition of precipitation regimes during the Holocene. During the early Holocene, relatively wet conditions occurred in the south–central and eastern Mediterranean regions, while drier conditions prevailed from 45° N northwards. These patterns then reverse during the late Holocene. With regard to the existence of a west–east precipitation dipole during the Holocene, our results show that the strength of this dipole is strongly linked to the reconstructed seasonal parameter; early-Holocene summers show a clear east–west division, with summer precipitation having been highest in Greece and the eastern Mediterranean and lowest over Italy and the western Mediterranean. Summer precipitation in the east remained above modern values, even during the late-Holocene interval. In contrast, winter precipitation signals are less spatially coherent during the early Holocene but low precipitation is evidenced during the late Holocene. A general drying trend occurred from the early to late Holocene, particularly in the central and eastern Mediterranean. For the same time intervals, pollen-inferred precipitation estimates were compared with model outputs, based on a regional-scale downscaling (HadRM3) of a set of global climate-model simulations (HadAM3). The high-resolution detail achieved through the downscaling is intended to enable a better comparison between site-based paleo-reconstructions and gridded model data in the complex terrain of the Mediterranean; the model outputs and pollen-inferred precipitation estimates show some overall correspondence, though modeled changes are small and at the absolute margins of statistical significance. There are suggestions that the eastern Mediterranean experienced wetter summer conditions than present during the early and late Holocene; the drying trend in winter from the early to the late Holocene also appears to be simulated. The use of this high-resolution regional climate model highlights how the inherently patchy nature of climate signals and paleo-records in the Mediterranean basin may lead to local signals that are much stronger than the large-scale pattern would suggest. Nevertheless, the east-to-west division in summer precipitation seems more marked in the pollen reconstruction than in the model outputs. The footprint of the anomalies (like today, or dry winters and wet summers) has some similarities to modern analogue atmospheric circulation patterns associated with a strong westerly circulation in winter (positive Arctic Oscillation–North Atlantic Oscillation (AO–NAO)) and a weak westerly circulation in summer associated with anticyclonic blocking; however, there also remain important differences between the paleo-simulations and these analogues. The regional climate model, consistent with other global models, does not suggest an extension of the African summer monsoon into the Mediterranean. Therefore, the extent to which summer monsoonal precipitation may have existed in the southern and eastern Mediterranean during the mid-Holocene remains an outstanding question.

The Pliocene (5.33-2.58 Ma), particularly the Early-Late Pliocene transition (~3.6 Ma), is a key period for understanding future climate change linked to increases in greenhouse gases. Around the Western Mediterranean Basin, the Early-Late Pliocene transition was marked by the establishment of a Mediterranean 20 climate with summer droughts, cool/wet winters and latitudinal gradients. However, environmental changes in the eastern part of the Mediterranean area during the Early-Late Pliocene transition have rarely been documented.Here, we propose to reconstruct the environmental and climate changes during the Early-Late Pliocene transition from the Lake Burdur sequence, located in Southwestern Türkiye. The aim of this study is to characterize the vegetation, lake dynamics, and water level changes based on pollen and Non-Pollen Palynomorph (NPP) proxies, 25 to quantitatively reconstruct climate changes using a multimethod approach (Modern Analogue Technique, Weighted Averaging Partial Least Squares regression, Random Forest, and Boosted Regression Trees and Climatic Amplitude Method) and morphologically characterize the large pollen grains of Poaceae (Cerealia-type). The results indicate that, during the Early-Late Pliocene transition at Burdur, the vegetation was dominated by steppes with Poaceae, Artemisia, and Amaranthaceae. Subsequently, arboreal taxa decreased and a 30 alternation between steppe grasslands with deciduous Quercus and steppes dominated by Amaranthaceae became evident. Large Poaceae pollen grains (Cerealia-type) are recorded in the Burdur sequence, but their percentages are lower than those at Acıgöl, a nearby record dated to the Pleistocene. The morphological characteristics of these large Poaceae pollen grains from Burdur are similar to those of domesticated cereals from recent periods, preventing a clear distinction between wild and domesticated Poaceae pollen. The lacustrine ecosystem was 35 characterized by semi-aquatic vegetation and freshwater algae, exhibiting alternating oligotrophic and eutrophic conditions. Climate reconstructions of Burdur show similar trends across different methods, with reconstructed values during the Early-Late transition being close to present-day values. Following a climatic optimum in precipitation and temperature, climate reconstructions indicate an alternation between cool, wet conditions and warmer, drier conditions during the Late Pliocene in Southwestern Anatolia. Around the Mediterranean Basin, 40 climate reconstructions during the Early Pliocene show warmer conditions compared to modern values and a northsouth gradient in terms of precipitation, with wetter conditions in the north in comparison to the south.

A pollen diagram was constructed for the early- to mid-Holocene transition (ca. 7350–5600 cal. B.P./5400–3650 B.C.) from the Burmarrad ria located in NW Malta. The vegetation at ca. 7350–6960 cal. B.P./5400–5010 B.C. was characterized by an almost tree-less steppe-like open landscape. Early Holocene dry climatic conditions were most probably due to intensification of the subtropical monsoon circulation that strengthened the subtropical anticyclonic descent over the central Mediterranean and blocked the penetration of humid air masses from the North Atlantic Ocean. At ca. 6950 cal. B.P./5000 B.C., the steppe-like vegetation was suddenly replaced by a Mediterranean evergreen forest or dense scrub dominated by Pistacia cf. lentiscus trees. This event, which has simultaneously been recorded in southern Sicily, was most probably caused by the southward shift of the ITCZ permitting the eastward movement of the North Atlantic cyclonic systems. Traces of human activities are evident in the pollen diagram since the beginning of the record but become more pronounced from the onset of the Temple Cultural Phase at ca. 6050 cal. B.P./4100 B.C. with a gradual decline of tree pollen. We suggest that the early- to mid-Holocene vegetation transformation was mainly controlled by a regional climatic change that occurred in a landscape only slightly impacted by human activities.

We reconstructed the paleohydrologic and climatic history of the Lake Neor region, NW Iran, from the end of the late glacial to the middle Holocene (15,500–7500 cal yr BP). Subfossil chironomid and pollen assemblages in a sediment core from a peatland located south of Lake Neor enabled identification of four main hydrologic phases. The period 15,500–12,700 cal yr BP was characterized by a relatively dry climate with an open landscape, suggested by the abundance of Irano-Turanian steppe plants (e.g. Amaranthaceae, Artemisia and Cousinia ). Dominance of several shallow-water and semi-terrestrial chironomid taxa (e.g. Pseudosmittia , Smittia/Parasmittia and Paraphaenocladius/Parametriocnemus ) during this period is indicative of lower water tables in the wetland. Between 12,700 and 11,300 cal yr BP, chironomid taxa indicate higher wetland water tables, as suggested by the presence of Zavrelia , Chironomus anthracinus/plumosus -type and Micropsectra , which are inhabitants of open-water, lacustrine areas. The open-steppe vegetation remained dominant in the watershed during this time. Increasing wetland moisture could be explained by: (1) cool summers that reduced the evaporation rate; and/or (2) a decrease in duration of the summer dry season. The period 11,300–8700 cal yr BP was characterized by lower wetland moisture, contemporaneous with a delay in the expansion of deciduous forest, suggesting persistent dry climate conditions throughout the beginning of the Holocene, which may have been related to the intensified seasonality of precipitation. Around 8700 cal yr BP, higher wetland water levels, inferred from chironomids, occurred simultaneously with the onset of regional deciduous forest expansion, probably caused by a shortening of the summer dry period. We concluded that chironomids are appropriate paleoecological proxies to investigate global and local hydrologic variability in the Middle East.