Case study of south-easterlies. Time series of winds (black is wind direction, left y-axis; dashed blue is wind speed, right y-axis) and selected NMHCs, and H₂S alongside NO_x for a period in mid July 2015 (DOY 197 = 16 July). Southerly to south-easterly winds were maintained throughout this period, and NMHC and H₂S abundances were significantly lower than shown in Figures 9 and 10. However, several spikes of alkenes on 17, 20 and 21 July were likely affected by local flare emissions (see text and Table 1). DOI: https://doi.org/10.1525/elementa.289.f11