Chimene Laure Daleu - A New Generalised Mass-Flux Convection Scheme for the Met Office Unified Model: Development and assessment

Event type: 
2 July 2020
4.00pm - 5.00pm

Via Zoom

Dr. Chimene Laure Daleu
The University of Reading, UK

The resolution in General circulation models (GCMs) determines the method of representing convection. Current digital computers cannot simulate global-scale processes with resolution down to the scale of individual clouds. As a results GCMs still rely heavily on parameterizations of processes happening at scales smaller than the model grid cell. These parameterizations are often developed and tested in single-column model (SCM) framework and then implemented in GCMs.  However, state-of-art GCM simulations are sensitive to the details of convective parameterization used and an improved convective parametrization may improve the ability of GCMs to simulate accurately the observed climate. A new generalised mass-flux convection scheme, called CoMorph, is being development as part of the NERC / Met Office ParaCon project. CoMorph enables representation of many additional physical processes that are not represented in the old convection scheme. The results from its assessment demonstrates clear improvements in model fidelity and performance.

Brief biography: Chimene Laure Daleu is a post-doctoral researcher at the department of Meteorology of the University of Reading where she works on the Parameterization of Convection (ParaCon) programme, which aims to revisit convection paramterization scheme of the UK Met Office. Her role in Phase 1 of ParaCon programme was to evaluate memory properties in the cloud-resolving simulations​ of the diurnal cycle of deep convection. In phase 2, she will focus on comparing CRM simulations against those from equivalent simulation with the Met Office Unified Model (UM) using the new CoMorph parameterization. Such comparisons will allow the assessment of CoMorph and contribute towards its development as an operational candidate scheme. 
Chimene obtained her PhD in 2013 from the University of Reading researching the use of the Large-Eddy-Model (LEM) of the UK Met Office to simulate the two-way interactions between tropical deep convection and large-scale circulation parameterized using the Weak-Temperature Gradient (WTG) approach. Her PhD was under the supervision of Robert PLANT and Steve WOOLNOUGH.