: Ozone layer Stratospheric layer containing much of the atmospheric layer containing much of the atmosphere’s ozone. Air pollution any gaseous or solid material in the atmosphere that occurs in concentrations high enough to alter climate or harm organisms, ecosystem, or human-made materials. Smog Unhealthy combination of air pollutants. Acid Deposition the falling of acids and acids-forming compounds from the atmosphere to earth’s surface. Sec 2: Climate Change, change in the global average atmospheric conditions over a period of at least three decades. Carbon Footprint, amount of carbon dioxide generated by an individual, organization, country, or any other entity over a given period of time. Drought, prolonged dry period in a given region. Atmospheric warming is a major cause if drought.