Climate-relevant land cover composition and configuration trajectories in Europe

Abstract Land use and land cover change (LULCC) can affect the climate system by altering biophysical surface characteristics. At the local scale, climate regulating functions are co-determined by land cover composition and configuration, i.e. the proportions and the spatial arrangement of land cover types. However, research on the relationship between LULCC and climate often focuses individually either on compositional or configurational aspects. As a result, there is a gap in our knowledge about the spatiotemporal distribution of land cover composition and configuration patterns influencing the local climate regulating functions. Here, we used a range of LULCC metrics between 1992 and 2015 and applied Self-Organizing Maps to characterize dominant land cover composition and configuration trajectories in Europe. We then tested the climate relevance of the five most dominant trajectories with a high-resolution regional climate model. Land cover composition and configuration simultaneously changed in more than 20% of the European landmass, with cropland transition to forest patches and bare soil representing the major trajectory. Climate model simulations predict a general increase in the topsoil temperature due to only changes in land cover composition and configuration. All trajectories showed increasing topsoil temperature variability during the crop growing season, with forest transition trajectories showing a greater increase. Our findings demonstrate the relevance of changes in both land cover composition and configuration for the local climate and warrant further empirical and model-based research with an explicit focus on quantifying the effects of simultaneous changes in both these LULCC dimensions.