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A new White House climate change report devotes a chapter to Alaska, where temperatures have risen twice at twice the rate of the rest of the country in the last half-century.

The state is the front line of climate change. Annual temperatures have risen 3.4 degrees Fahrenheit in 50 years and are projected to rise another 3.5 to 7 degrees by midcentury, the report states.

The report, a compilation of current science, translates what that change means in practical terms:

• Sea ice is melting, meaning shipping and resource extraction can expand. Arctic ice could be gone during summers by the end of the century.

• Marine species are moving, mostly northward. Fishermen will have to go farther to get to the most productive commercial fisheries. Alaska Natives may have trouble getting the walruses and seals they subsist on.

• Coastlines are eroding tens of feet per year, and that rate is picking up. Villages like Newtok and Shishmaref are crumbling into the sea and having to decide between relocation and expensive engineering solutions.

• The coasts and the Bering Sea are getting stormier, throwing off autumn barge delivery schedules and making commercial fishing more dangerous.

• As the permafrost melts, the land sinks. This will add between $3.6 billion and $6.1 billion, or 10 to 20 percent, to future costs for publicly owned infrastructure by 2030. That's not including the cost of the thawing to private property.

• In the last 30 years, the number of days each year that the Department of Natural Resources allows oil-and-gas-related truckers to travel on tundra ice roads has halved, from 200 to 100.

• The average area burned in North American wildfires each year - affecting subsistence resources and clean air - tripled from the 1960s to the 1990s. Alaska's wildfire burn area is conservatively projected to double by midcentury and triple by 2100.