Christiana Figueres, who helped secure the 2015 Paris climate change agreement, has given BBC Radio 5 Live a list of five things people can do to help the environment.
These included looking at food, transport and how homes are insulated.
Ms Figueres is the former executive secretary of the UN Framework Convention on Climate Change. She now uses her organisation, Mission 2020, to pressure countries to do more about global warming.
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