The president of Kiribati who fears that his Pacific island nation could be swallowed by a rising ocean, says a visit to the melting Arctic has helped him appreciate the scale of the threat.

President Anote Tong on Saturday ended a Greenpeace-organized tour of glaciers in Norway's Svalbard Archipelago, a trip he said left a deep impression that he would share with world leaders at a U.N. climate summit next week in New York.

Scientists say the melt of Arctic glaciers is a key factor in the sea level rise that is threatening island nations such as Kiribati, an impoverished string of 33 coral atolls located about halfway between Hawaii and Australia. Many of its atolls rise just a few feet above sea level.