Over the last few decades, air quality in the San Joaquin Valley has greatly improved. But climate change could jeopardize those gains, and researchers are trying to figure out by how much. One of the Valley’s summertime air pollutants is ozone. High in the atmosphere, the gas protects the Earth, but at ground level it’s a contributor to the summer smog that obscures views of our surrounding mountains and turns the sky a sickly brown. Exposure to ozone is known to exacerbate respiratory ailments , and recent research out of UCLA suggests it’s associated with the development of type-II diabetes . Ozone itself is not directly emitted, but it’s produced when other harmful pollutants like volatile organic compounds (VOCs) and oxides of nitrogen (NOx) combine in the air. Both ozone precursors are emitted by combustion engines and many industrial sources including manufacturers and refineries, although VOCs are also emitted naturally by plants and released during forest fires. As a result of