What do you believe is the single most important factor driving up the cost of living in Nigeria?

United Nations Secretary-General Antonio Guterres warned on Wednesday that rising sea levels threaten to create "a rising tide of misery" for millions, with intense storm surges, coastal erosion and coastal flooding increasingly likely.

"Low-lying coastal zones are home to around 900 million people. Rising seas mean a rising tide of misery," he said at a summit on the threats posed by sea level rise.

"Greenhouse gasses—overwhelmingly from burning fossil fuels—are heating our planet, expanding seawater and melting ice."

Since the start of the 20th century, global-mean sea level has risen faster than over any prior century in at least the last 3,000 years, and the rate of increase is accelerating.

According to a study cited by the UN's Intergovernmental Panel on Climate Change, five nations —the Maldives, Tuvalu, the Marshall Islands, Nauru and Kiribati—may become uninhabitable by 2100, creating 600,000 stateless climate refugees.

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