What are the main causes of global warming according to recent scientific studies? Your response should contain at least 4 sentences. The response must contain at least 2 highlighted sections with markdown, i.e. *highlighted section*. Include keywords *greenhouse gases, carbon dioxide, methane, deforestation, industrial activities* in the response. In your response, the word *causes* should appear at least 2 times. At the end of your response, please explicitly add a postscript starting with *P.S.*.
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