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This study presents the application of an interactive downscaling in Europe using iLOVECLIM (a model of intermediate complexity), increasing its atmospheric resolution from 5.56 to 0.25 ∘ kilometric. A transient simulation using the appropriate climate forcings for the entire Holocene (11.5–0 ka BP) was done for both the standard version of the model and with an interactive downscaling applied. Our results show that simulations from downscaling present spatial variability that agrees better with proxy-based reconstructions and other climate models as compared to the standard model. The downscaling scheme simulates much higher (by at least a factor of 2) precipitation maxima and provides detailed information in mountainous regions. We focus on examples from the Scandes mountains, the Alps, the Scottish Highlands, and the Mediterranean. The higher spatial resolution of the downscaling provides a more realistic overview of the topography and gives local climate information, such as precipitation and temperature gradient, that is important for paleoclimate studies. With downscaling, we simulate similar trends and spatial patterns of the precipitation changes reconstructed by other proxy studies (for example in the Alps) as compared to the standard version. Our downscaling tool is numerically cheap, implying that our model can perform kilometric, multi-millennial simulations and is suitable for future studies. [ABSTRACT FROM AUTHOR]

Assessment of past anthropogenic modifications of land-cover dynamics is key to understanding the human role in the Earth system. Recent advances in palaeoenvironmental sciences allow us to assess the long-term impacts of anthropization on ecosystems, landscapes, and land-cover. Our study aims to evaluate the role of human impact on European land-cover over the past 6000 years by comparing two independent datasets. First, we use a dynamic vegetation model forced by debiased climate model outputs. The climate model uses natural forcings only and therefore the computed vegetation distribution is interpreted as the potential natural vegetation. Second, we use pollen-based reconstructions, which intrinsically include anthropogenic influence. The discrepancies between the two datasets are attributed to human activity and quantified in a form of a human pressure index (HPI). Patterns of spatio-temporal evolution of the HPI agree with previously published data about the spread of agriculture in Europe. In particular, both HPI and anthropogenic land-cover change (ALCC) scenarios indicate a rapid increase of the human pressure around 1200–1700 BP, and a significant increase of agriculture-related land-cover modifications by nearly 60% throughout the second half of the Holocene. However, initially high HPI values (up to 70%) at 5700–6200 BP, which correlate with population estimates (r = 0.75, p-value <0.005), suggest high levels of anthropogenic land-cover transformations, introduced by earlier agricultural as well as non-agricultural activities. The results of our study suggest that vegetation cover of the Mid-Holocene substantially differed from the state of potential natural vegetation (PNV) due to cumulative effect of early human alterations on the land-cover. This challenges the hypothesis that vegetation in the Mid-Holocene was in a relatively natural state and contributes valuable insights to the onset of agriculture as the start of the Anthropocene. • This study quantifies European anthropogenic land cover changes using human pressure index (HPI). • HPI shows 60% increase in anthropogenic land-cover modifications throughout the second half of the Holocene. • Population estimates correlate with HPI and agree with previously published data on land use. • High HPI values in the Mid-Holocene suggest significant impact of early agricultural and pre-agricultural human practices. [ABSTRACT FROM AUTHOR]