contributing to the fresh, vegetal smell of petrichor.The formation of ozone in the atmospherecan also be a factor if there is a thunderstorm. Lightning is so powerful that it can split molecules of oxygen and nitrogen to form nitric oxide and ozone, which has ...
Any thunderstorm, large or small, begins as an updraft, a column of warm, moist air moving upward due to its positive buoyancy (i.e., lower density; think a balloon or heat rising from the pavement on a hot summer day). Due (mostly) to its temperature, once the air is less dense ...