Cloudy skies

The atmosphere is remarkably cloudy. With a group of motivated scientists I study the impact of convective clouds on weather and climate. In particular, I try to understand how convective clouds are coupled to wind and circulations. Read more about my research projects below.

Cloud - Wind Interaction

Funded projects:

CMTRACE - Can we trace convective momentum transport in complex cloudy atmospheres? Clouds often visualize how the wind blows, but rarely are cloud measurements used to understand how clouds themselves change winds. The NWO VIDI project CMTRACE (2019-2024) combines wind lidar and cloud radar measurements with fine-scale simulations to visualize the patterns of wind in diverse cloud fields and identify mechanisms that are key to convective momentum transport (CMT). New data and acquired insights will be used to improve weather prediction models.

CloudBrake: How do shallow clouds slow down circulations? The ERC Starting Grant CloudBrake project (2017-2022) strives to expose relationships between shallow clouds and the vertical structure of wind, and to estimate the amount of cumulus friction that takes place in different large-scale flows, such as in the large-scale Hadley circulation. A better understanding of cloud-wind interactions is important for numerical weather prediction, climate modeling, and wind energy design. The research carried out combines high-resolution modeling (Large Eddy Simulation) and global modeling with the analysis of existing and new observations from ground and from space.

Research themes

Trimodal convection

In nature, moist convection prefers three modes: shallow, congestus and deep cumulus. Using a conceptual model, can we understand what processes help set the depth of convection in tropical circulations?

Warm rain over oceans

Warm rain is that produced by clouds with tops below the freezing level. Observations reveal that warm rain is a significant part of rainfall over global oceans, with implications for atmospheric dynamics.

Vertical structure of low cloud

Global models disagree on how low clouds respond to increasing carbon dioxide concentrations, and observations show how this behavior might relate to the vertical structure of low cloud produced by models.