Ключевые слова: air, atmosphere, background, chemical, chimney, city, climate, cloud, clouds, co2, coal, damage, dioxide, dirty, ecology, emissions, energy, environment, environmental, exhaust, factory, fuel, fumes, gas, global, gray, gray smoke, grey, industrial, industry, manufacturing, nature, pipe, plant, pollution, power, production, sky, smog, smoke, smokestack, stack, station, steam, technology, tower, toxic, vapor, warming,