Despite significant steps to cut air pollutants, one of the most dangerous products of these gases remains stubbornly prevalent in our atmosphere.  Overall, between 2000 and 2018 North America and Europe brought ‘ozone precursor emissions’ down by around 50%. This covers nitrogen oxides (NOx) and volatile organic compounds, among others, which contribute to the development … Continue reading If ozone emission precursors have fallen, why haven’t ozone levels?