Carbon dioxide emitted from human activities like burning fossil fuels is the main pollutant causing global warming. Other greenhouse gases like methane from livestock and CFCs also contribute. Sulfur dioxide is another pollutant associated with climate change and acid rain. To curb global warming, individuals can reduce their carbon footprint by driving and flying less, recycling, and conserving energy. Governments are also taking measures like the Kyoto Protocol to limit greenhouse gas emissions through emissions reductions and carbon taxes.