Ключевые слова: air, atmosphere, background, carbon, chemical, chimney, climate, co2, coal, contamination, danger, dioxide, dirty, ecology, electricity, emission, energy, exhaust, factory, fog, fuel, fumes, future, gas, global, harm, industrial, industry, manufacturing, nature, pipe, plant, pollution, power, problem, production, refinery, sky, smog, smoke, station, steam, steel, sun, technology, tower, toxic, vapor, warming,