Ключевые слова: air, atmosphere, background, blue, building, business, chemical, chemistry, chimney, city, climate, cloud, coal, contamination, damage, dioxide, dirty, ecology, emission, emissions, energy, environment, environmental, exhaust, factory, fuel, fume, gas, global, health, industrial, industry, landscape, manufacturing, nature, pipe, plant, pollution, power, production, sky, smog, smoke, steam, technology, tower, toxic, warming, white,