The temporal trend of wind speed near the surface over land has been
investigated over recent decades. A prevailing trend of decline was
found in several studies for most areas in the Northern hemisphere,
denoted as terrestrial stilling, with multiple causes being discussed.
In this study, we focus on the impact of changes of surface roughness
due to changes in land-use and vegetation cover on this variable for
western Europe using the regional climate model RACMO driven by ERA5
reanalysis. We conduct two simulations at climate scale, with and
without changes in land-use and vegetation on a yearly basis. We find
that upper level large-scale circulation slowing down results in
declining near surface mean wind speed, and that increases in surface
roughness due to changes in land use and vegetation cover play an
important role in intensifying this declining trend from our simulations
with RACMO. However, the trends inferred from the model simulations and
ERA5 are not consistent with trends derived from gridded observations
database E-OBS. This could come from the complexity of integrating
in-situ measurements with uncorrectable inhomogeneity to derive E-OBS.