I don't know anyone who has claimed that communism will stop climate change. One of the main drivers of climate change is the burning down of the rain forest in South America, and that is being done primarily to grown grain to feed to beef cattle. The only way climate change could be reversed at this point would be for people to stop eating beef and start replanting the lost rainforest. (Even then, it would take hundreds of years for the forest to grow enough to have a significant impact.) I'm not holding my breath. We're basically screwed.
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