In this study, we present the findings of a sediment core retrieved from Klisova lagoon, Western Greece, an area with a long record of documented human presence. The recovered deposits were subjected to sedimentological, XRF, and micropaleontological analyses. For the last 4700 cal BP, the freshwater influx, the progradation of the Evinos river delta and related geomorphological changes control the environmental conditions in the lagoon. Considering the centennial temporal resolution of our analyses, small offsets of c.a. 50 years due to lack of regional reservoir correction do not considerably impact the reported radiocarbon ages. Prior to 4000 cal BP, a relatively shallow water depth, significant terrestrial/freshwater input and increased weathering in the lagoon area are inferred. Elemental proxies and increased dinoflagellate cyst and foraminiferal abundances, which indicate marine conditions with prominent freshwater influxes, point to the gradual deepening of the lagoon up to 2000 cal BP. The marine and freshwater condition equilibrium sets at 1300 cal BP, with the lagoonal system reaching its present state. Maxima of anthropogenic pollen indicators during the Mycenaean (3200 cal BP), Hellenistic (2200 cal BP), and Late Byzantine (800 cal BP) periods suggest intervals of increased anthropogenic activities in the area.

Vegetation patterns during the 1st millennium AD in the central Mediterranean, exhibit a great variability, due to the richness of these habitats and the continuous shaping of the environment by human societies. Variations in land use, witnessed in the pollen record, reflect the role that local vegetation and environmental conditions played in the choices made by local societies. The interdisciplinary study of off-site cores remains the key evidence for palaeoenvironmental transformations mirroring the ‘semi-natural’ vegetation, and revealing temporal fluctuations and the amount of human impact on a regional scale.

No abstract

The Black Death is the most reknown pandemic in human history, believed by many to have killed half of Europe's population. However, despite the advances in ancient DNA research that allowed for the successful identification of the pandemic's causative agent (bacterium Yersinia pestis), our knowledge of the Black Death is still limited, based primarily on medieval texts available for single areas of Western Europe. In our study we remedy this situation and we focus in particular on the scale of the Black Death mortality. We collected data on landscape change from 261 coring sites (lakes and wetlands) located in 19 European countries. We used two independent methods of analysis to evaluate whether the changes we see in the landscape at the time of the Black Death agree with the hypothesis that half of the population died within a single year in each of the 21 regions we studied. We discovered that while the Black Death had devastating impact in some regions, it had negligible or no impact in others. The inter-regional differences in the Black Death mortality across Europe demonstrate the significance of cultural, ecological, economic and climatic factors that mediate the dissemination and impact of the disease. The complex interplay of these factors, along with the identification of the pathogen that caused disease outbreaks, should be the focus of future research on historical pandemics.

Abstract. Climate evolution of the Mediterranean region during the Holocene exhibits strong spatial and temporal variability. The spatial differentiation and temporal variability, as evident from different climate proxy datasets, has remained notoriously difficult for models to reproduce. In light of this complexity, we examine the previously described evidence for (i) opposing northern and southern precipitation regimes during the Holocene across the Mediterranean basin, and (ii) an east-to-west precipitation gradient or dipole during the early Holocene, from a wet eastern Mediterranean to dry western Mediterranean. Using quantitative climate information from marine and terrestrial pollen archives, we focus on two key time intervals, the early to mid-Holocene (8000 to 6000 cal yrs BP) and the late Holocene (4000 to 2000 yrs BP), in order to test the above mentioned hypotheses on a Mediterranean-wide scale. Palynologically derived climate information is compared with the output of regional-scale climate-model simulations for the same time intervals. Quantitative pollen-based precipitation estimates were generated along a longitudinal gradient from the Alboran (West) to the Aegean Sea (East); they are derived from terrestrial pollen records from Greece, Italy and Malta as well as from pollen records obtained from marine cores. Because seasonality represents a key parameter in Mediterranean climates, special attention was given to the reconstruction of season-specific climate information, notably summer and winter precipitation. The reconstructed climatic trends corroborate a previously described north-south partition of precipitation regimes during the Holocene. During the early Holocene, relatively wet conditions occurred in the south-central and eastern Mediterranean region, while drier conditions prevailed from 45° N northwards. These patterns reversed during the late Holocene, with a wetter northern Mediterranean region and drier conditions in the east and south. More sites from the northern part of the Mediterranean basin are needed to further substantiate these observations. With regard to the existence of a west-east precipitation dipole during the Holocene, our pollen-based climate data show that the strength of this dipole is strongly linked to the seasonal parameter reconstructed: Early Holocene summers show a clear east-to-west gradient, with summer precipitation having been highest in the central and eastern Mediterranean and lowest over the western Mediterranean. In contrast, winter precipitation signals are less spatially coherent. A general drying trend occurred from the early to the late Holocene; particularly in the central and eastern Mediterranean. However, summer precipitation in the east remained above modern values, even during the late Holocene interval. Pollen-inferred precipitation estimates were compared to regional-scale climate modelling simulations based on the HadAM3 GCM coupled to the dynamic HadSM3 and the high-resolution regional HadRM3 models. Climate model outputs and pollen-inferred precipitation estimates show remarkably good overall correspondence, although many simulated patterns are of marginal statistical significance. Nevertheless, models weakly support an east to west division in summer precipitation and there are suggestions that the eastern Mediterranean experienced wetter summer and winter conditions during the early Holocene and wetter summer conditions during the late Holocene. The extent to which summer monsoonal precipitation may have existed in the southern and eastern Mediterranean during the mid-Holocene remains an outstanding question; our model, consistent with other global models, does not suggest an extension of the African monsoon into the Mediterranean. Given the difficulty in modelling future climate change in Southern Europe, more simulations based on high resolution global models and very high resolution regional downscaling, perhaps even including transient simulations, are required to fully understand the patterns of change in winter and summer circulation patterns over the Mediterranean region