- Turbulence in canopies with an emphasis on scalar transport in and above the canopy. Research is based both on observations and large-eddy simulation.
- Turbulence in the convective boundary layer, with particular emphasis on (dis-)similarities between different scalars. My work focuses on heterogeneity in surface properties and the effect of dissimilar entrainment ratios.
- The practical link between turbulent transport and the surface energy balance. This work encompasses the estimation of the surface evapotranspiration from remote sensing data, land-surface models in atmospheric models and the use of forecasted meteorological data in the prediction of the spread of plant diseases.
- Member of the editorial board of Boundary-Layer Meteorology (since 2010).
- Member of the AMS Committee on Boundary Layer Turbulence (since 2012).
- Authored (together with Jos van Dam, also of Wageningen University) a text-book on 'Transport in the Atmosphere-Vegetation-Soil continuum' , published in 2014 by Cambridge University Press.
- Reviewer of papers for a wide range of journals.