Ключевые слова: agreement, air, backdrop, background, business, carbon, cfc, change, chlorofluorocarbons, clean, climate, co2, combustion, concept, contamination, control, dioxide, earth, ecological, ecology, effect, emission, energy, environment, exhaust, factory, free, gas, ghg, global, greenhouse, hot, industry, issue, letter, limit, methane, natural, nature, ozone, policy, pollutant, pollution, problem, smog, smoke, sustainable, warming, word, zero,