CL5.04/AS1.28CL5.04/ AS1.28

Convection-permitting atmospheric modelling (co-organized) 
Convener: Edmund Meredith  | Co-conveners: Stefan Sobolowski , Merja Tölle , Hayley Fowler , Heimo Truhetz 
This session explores advances and challenges in convection-permitting atmospheric modelling: using the newest generation of atmospheric models that allow for the explicit treatment of convective processes (grid spacing ≤ 4 km).

Convection-permitting models (CPMs) are a rapidly growing area of research and have been shown to improve both the diurnal convective cycle and the representation of convective precipitation, particularly extremes. Furthermore, CPMs often exhibit important differences in feedback mechanisms and climate change signals compared to models with parametrized deep convection. CPMs offer a promising tool to better understand fine-scale processes and provide critical information to stakeholders, especially in areas affected by convective extremes and mountainous regions, and have thus sparked wider interest in their applications and development. For example, the CORDEX Flagship Pilot Study (FPS) on convective phenomena over Europe and the Mediterranean.

The session brings together numerical modellers, the observational community, cloud physicists, forecasters and CORDEX-FPS participants, with the aim of advancing understanding of convection and high-resolution modelling in general (including convective storm life cycle and convective organization) with new modelling and statistical observation approaches. Contributions on new high-resolution/sub-daily observational datasets, and their application to CPM evaluation, are particularly welcome. This session calls for papers on state-of-the-art development and application of CPM activities, including examination of interactions between convection and other atmospheric phenomena (e.g. boundary layers, cloud physics, radiation), as well as CPM investigations of local- to regional-scale phenomena (e.g. land-use change, land-ocean contrasts, flow-orography interactions, urban-rural transitions, aerosol effects, etc.). We welcome studies of past, present or future climates, and CPM modelling across time scales. Particular attention is given to extremes.

Other topics include, but are not limited to:
-- Model setup and parametrization, including sensitivity to resolution and dynamics
-- Model evaluation and new evaluation metrics/methods
-- Ensemble-based approaches to quantify predictability/uncertainty at convective scale
-- Physical understanding of the added value compared to coarser models
-- Land-atmosphere coupling at convection-permitting scale
-- Application to climate studies
-- Tropical phenomena
-- Convection, energy balance and hydrological cycle
-- Lightning in CPMs
-- Teleconnection across scales
-- Novel high-resolution experiments

The session will include a solicited talk from Christoph Schär (ETH Zürich) on prospects and challenges in convection-resolving modelling. The session will be chaired by S Sobolowski.