Climatological analysis of simulations of cold air pooling from the COLPEX Campaign

Cold air pooling is a phenomena whereby a pool of cold air collects or forms in valleys. Forecasting cold air pooling is an interesting challenge since cold air pools are dominated by processes currently unresolved in forecast models on scales typical of cold air pooling in the UK landscape. The COLPEX (COLd-air Pooling EXperiment) campaign brings together intensive observations and high resolution modelling to better understand cold air pooling in complex terrain. COLPEX focuses on the Clun valley in Shropshire, UK. Observations include three main mast sites, a number of automatic weather stations, lidar and radiosonde profiles. An extended simulation of the Clun valley region has now been completed using the Met Office Unified model, run at 100m horizontal resolution for a period of two months. Analysis of the cold pool climatology of this simulation will be presented, examining the ability of the model to reproduce the observed variability in cold pool behaviour. Analysis of the synoptic factors driving cold air pooling will also be presented. In-depth analysis of single night case studies will be discussed in a separate talk.