Ключевые слова: air, atmosphere, background, blue, business, cast iron, chemical, chimney, city, climate, coal, construction, dioxide, dirty, ecology, emission, emissions, energy, environment, environmental, factory, fuel, fume, gas, global, industrial, industry, landscape, manufacturing, metal, metallurgy, ozone, pipe, plant, pollution, power, production, refinery, silhouette, sky, smog, smoke, stack, steam, steel, sun, technology, tower, toxic, warming,