Prime Minister Justin Trudeau invoked the memory of Lytton, B.C., as he called for global action in the fight against climate change and formally committed to a cap on emissions produced by Canada’s oil and gas sector. The prime minister spoke at the 26th meeting of the Council of Parties to the UN climate convention, known as COP26, where more than 120 world leaders are gathering for two days to assess global efforts to address what many see as an existential problem.