This dataset contains output from an inert-tracer study using the Met Office HADGEM2-GA4 model. The aim of the study was to analyse why omega block events are associated with such hazardous particulate matter (PM) within the UK.

The dataset includes HADGEM3-GA4 Chemistry-Climate simulation output and nudged Blocking Index Metrics (blocking index, direction of blocking index and relative importance of air masses Indices) for the same time period. These are calculated on the theta = 2 PVU field (dynamical tropopause).