What are the six major pollutions in the National Ambient Air Quality Standards (NAAQS)? Briefly explain dry adiabatic lapse rate? What is the value of the dry adiabatic lapse rate? How does the dry adiabatic lapse rate affect atmospheric stabillity?, Explain briefly In general, how many stability categories can you name? What are they? Solution The six major pollutants per NAAQS are sulphur dioxide, particulate matters (PM10 and PM2.5), carbon monoxide, ozone, nitrogen dioxide and lead the lapse rate observed in air when the air has little or no water is called dry adiabatiuc lapse rate value of dry adiabatic lapse rate is 9.8oC/km.