ANCHORAGE, Alaska — Submerged countries, abandoned cities and floods of refugees await the world barring urgent action on climate change, President Barack Obama warned Monday, painting a doomsday scenario as he opened a historic visit to Alaska.

In a bid to further his environmental legacy, Obama brought the power of the presidential pulpit to Anchorage and called on other nations to take swift action as negotiations for a global climate treaty near a close. His speech to an Arctic climate summit set the tone for a three-day tour of Alaska that will put the state’s liquefying glaciers and sinking villages on graphic display.

“On this issue — of all issues —there is such a thing as being too late,” Obama said. “And that moment is almost upon us.”

During his tour of Alaska, Obama planned to hike a glacier, converse with fishermen and tape a reality TV show with survivalist Bear Grylls — all part of a highly orchestrated White House campaign to illustrate how climate change has damaged Alaska’s stunning landscape. The goal at each stop is to create powerful visuals that show real-world effects of climate change and drive home Obama’s message that the crisis is already occurring.

Obama has two audiences in mind as he traverses Alaska this week: Alaskans, who are hungry for more energy development to boost the state’s sagging oil revenues, and the broader public, whose focus Obama hopes to concentrate on the need for drastic action to combat global warming, including a climate treaty that he hopes will help solidify his environmental legacy.

Whether Obama can successfully navigate those competing interests — energy and the environment — remained the prevailing question of his trip.

The president has struggled to explain how his dire warnings and call to action to cut greenhouse gases square with other steps he’s taken or allowed to expand energy production, including oil and gas. Environmental groups took particular offense at the administration’s move to allow expanded drilling off Alaska’s northwest coast — just a few weeks before Obama arrived in Alaska to preach on climate change.