Evaluating automated pollen monitoring for thunderstorm asthma and public health forecasting: a comparative study in...

High-quality pollen measurements are essential for effective environmental monitoring and reliable public health forecasting. Automated pollen counters offer continuous, high-resolution observations that have the potential to reduce reliance on labour-intensive manual microscopy, but their performance must be evaluated against established methods. This study evaluates the performance of the SwisensPoleno Mars by comparing its daily and sub-daily pollen measurements of total pollen, and the two dominant airborne pollen types in Melbourne, grass and cypress, with those from a co-located Burkard Hirst-type spore trap at the University of Melbourne over the 92-day spring monitoring period in 2022. Data from the automated system showed a strong linear relationship with the co-located manual trap, with coefficients of determination (R²) of 0.92 for total daily pollen counts, 0.92 for grass pollen, and 0.86 for cypress pollen. Grass pollen measurements, which are central to epidemic thunderstorm asthma (ETSA) risk forecasting in Victoria, showed particularly high correspondence, including consistent classification into low, moderate, and high operational thresholds. The SwisensPoleno Mars also reproduced expected diurnal variation in pollen concentrations, demonstrating its ability to capture short-term changes in airborne pollen levels. These results indicate that automated pollen counters can deliver reliable observations at both daily and sub-daily scales while substantially reducing labour demands. The strong performance of the automated system supports its use for routine pollen monitoring, its suitability for supplementing or replacing manual counting in Victoria and its value and suitability for applications that benefit from high temporal resolution, including ETSA risk forecasting.