Ключевые слова: air, atmosphere, background, building, chemical, chimney, city, climate, cloud, clouds, contamination, damage, danger, dioxide, dirty, ecology, emission, energy, environment, environmental, factory, fuel, fume, gas, global, industrial, industry, landscape, nature, ozone, pipe, plant, pollution, power, sky, smog, smoke, smokestack, steam, storm, sun, sunrise, sunset, technology, tower, toxic, warming,