Since the last ITM in October 2016, the Canadian operational Regional Air Quality Deterministic Prediction System (RAQDPS) has been ported to a new high-performance computing system and has been updated to use a new meteorological initialization method, a new meteorological “piloting” model, a new and faster version of the GEM-MACH code, and a new set of input emissions files and to produce an expanded set of output fields. These updates are briefly described and some examples are given of their impact on RAQDPS forecast performance, including improved NO2 forecasts and a large reduction (~10 ppbv) in summertime ozone overpredictions for the eastern United States.
