Dr Leif Denby

Profile

I am a PostDoc on the GENESIS project which is the University of Leeds component of the NERC and Met Office programme ParaCon. Within GENESIS we are studying the thermodynamics and dynamical properties of coherent structures in the atmospheric boundary layer which lead to formation of convective clouds, and through this aim to quantify driving mechanisms which determine the properties of convective updrafts and how these combine to effect the temporal evolution of individual and ensembles of clouds. This research plays a key role in building together with the ParaCon partners a new convection parameterisation for the operational MetOffice model.

During my PhD research I used high-resolution (Large-Eddie Simulation, LES) modelling to study the full dynamic behaviour of developing convective clouds. My research focussed on quantifying the predictive skill of a 1D Lagrangian cloud-model by comparing against LES of individual convective clouds and studying the assumptions and cloud-based forcing assumed in the Convective Cloud Field Model (CCFM, Wagner and Graf, 2012). Through this research I identified the need for further research into the dynamic behaviour of entrainment in 3D clouds (as compared to axisymmetric clouds), the importance of considering the near-cloud environment when estimating the effect of entrainment and also examined the cloud-producing boundary thermals which cause the formation of moist convective updrafts.

My passion is the intersection between computers and science. During my Physics undergrad I worked in the Bullard Labs, Cambridge on computational seismic analysis and during the summers on human-computer interaction in the Inference Group, Cavendish Laboratory. During my MPhil in Scientific Computing I researched high-order adaptive-grid methods for atmospheric numeric modelling.

I am an active contributor to open-source tools and use Python extensively in my research.

Research interests

• The dynamics and topological structure of convective clouds, the updrafts within them and their correlation with coherent structures in the atmospheric boundary layer
• The interaction between large-scale flow and moist convection
• Novel visualisation and analysis techniques which can be used to answer new questions in science
• HPC to facilitate scientific research

Qualifications

• PhD, Atmospheric Physics, University of Cambridge
• MPhil, Scientific Computing, University of Cambridge
• MSci, BA, Physics (NatSci), University Cambridge

Research groups and institutes

• Institute for Climate and Atmospheric Science

Current postgraduate researchers

• Jonathan Coney
• Jakub Lewandowski
• Flo Greaves