Regional climate modelling for a comprehensive understanding of forest management-induced biogeophysical climate impacts in Europe

Forests play a crucial role in European climate policy, owing to their potential for carbon sequestration, climate adaptation, biodiversity conservation, and other ecosystem services. Forest management directly changes land surface properties, e.g., albedo and roughness, and therefore has biogeophysical (BGP) impacts locally and potentially remotely due to advection and circulation. Previous studies investigating BGP climate impacts of forests focused on af/de-forestation, neglecting other types of forest management, like species change, tree health improvement, etc. To fill this gap, we employ the regional climate model COSMO-CLM, coupled with a land surface model with elaborate forest representation, CLM5, to perform simulations under multiple forest management scenarios. These scenarios vary in forest coverage, forest composition, and forest health (represented by leaf area index and canopy height), which allow us to detect the changes in climate induced by different forest management types and their combinations. The first results show that forest management-induced impacts have substantial spatial- and temporal- heterogeneity. Key findings include (i) both deforestation and broadleaf trees afforestation can decrease summer daily maximum temperature; (ii) broadleaf trees also increase winter daily minimum temperature in mid-latitude areas compared to needleleaf trees; (iii) afforestation increases precipitation in coastal regions of West Europe; and (iv) needleleaf trees afforestation decreases precipitation in the inland of Europe, but broadleaf trees afforestation increases it, etc. In our ongoing work, we will focus on understanding the mechanism behind these impacts by investigating changes in energy fluxes, water fluxes, wind speeds and other relevant variables.