Datasets for AQUAS-Tsukuba in 2017

We conducted ambient observations to measure the total hydroxyl radical (OH) reactivity and mixing ratios of trace species for the summer campaign air quality study in Tsukuba (AQUAS-Tsukuba), August of 2017. The total OH reactivity was directly measured via laser-flash photolysis and laser-induced fluorescence. Continuous measurements of more than 50 trace species yielded information about each species’ individual OH reactivity contribution. We found that the observation site is influenced by polluted air masses originating from the megacity of Tokyo as well as clean air masses from the mountainous and oceanic regions, depending on the wind direction. Based on our results, it was concluded that around three times the ozone production potential is expected when we model ozone potential with the contribution of missing OH, which accounts for 53% of total OH reactivity. We also estimate the maximum ozone production potential to be around 11 ration in the range of 5 to 10 ppbv NOx. AQUAS-Tsukuba may thus be characterized as a volatile organic compound limited (VOC-limited) regime.