In addition to localized acid fog, the sulphuric and nitric acids that make rainwater acidic can also attach themselves to microscopic particulates (dust) suspended in the air, so they can be said to exist in gaseous form too.
除了地區性的酸霧，由於造成雨水酸化的硫酸根、硝酸根會吸附在空氣的懸浮微粒（灰塵）中，可以說它也能以「氣體」形態存在。