Improvements to the Regional Deterministic Air Quality Analysis System for Surface Pollutants including AQHI at the Canadian Meteorological Center

In February 2013, in collaboration with the Air Quality Research Division, the Canadian Meteorological Centre (CMC) implemented into operations a new surface analysis (RDAQA) for air quality species (ozone and PM2.5). Since 2013 RDAQA has been upgraded by including new pollutants: nitrogen dioxide (NO₂), coarse particulate matter (PM₁₀), sulfur dioxide (SO₂) and the air quality health index (AQHI).

The RDAQA System is connected to two slightly different configurations of the same model namely operational GEM-MACH and FireWork-GEM-MACH respectively. The two RDAQA analyses are produced hourly using the two model configurations (trial fields) and surface observations obtained from Canadian regional data providers and the US EPA/AIRNow Program. The solver which blends model and observations is an improved version based on the classical optimal interpolation approach with a semi-empirical bias correction algorithm.

This poster will focus on the current situation on the RDAQA which uses an improved version of model and upgraded error statistics. The evaluation of analysis by cross-validation tests will be presented together with information about using verification metrics such as the modified normalized mean bias, the fraction of correct within a factor of 2, the variance and the correlation coefficient. It will be shown that by leaving observations out of the analysis we can evaluate the true analysis error variance.