Pentagon Comptroller Robert Hale, Navy Secretary Ray Mabus and a Who's Who of other VIPs braved below-zero temperatures this month to visit a temporary camp on the ice about 150 miles north of Prudhoe Bay, Alaska, where two nuclear-powered U.S. submarines are conducting military training exercises.

He said U.S. submarines are a powerful symbol of U.S. military power, and the training was meant to ensure that the United States maintained access to the Arctic, home to the world's largest undiscovered oil and gas reserves.

It is a key potential transit line between the Atlantic and the Pacific. We want to be able to demonstrate that we have global reach. That we can operate in all oceans, and that we can operate proficiently in any environment, Jaehn said.

Russia, the United States, Denmark, Greenland, Canada and Norway, which border the Arctic, and China are already jockeying for position to benefit from new business opportunities there.

Navy scientists predict the Arctic will have one ice-free summer month in about the mid-2030s, and two to three ice-free months by around mid-century. Less ice means the 56-mile wide Bering Strait between Russia and Alaska could one day compete with the Persian Gulf and other shipping lanes because it is as much as 40 percent shorter than conventional routes.

Changing ice conditions in the Arctic are expected to lead to greater commercial traffic, increasing the need for submarine and Coast Guard patrols.

The Navy's chief oceanographer, Rear Admiral David Titley, who visited the camp last week, said just finding a thick enough multi-year ice sheet to put the camp was difficult this year.

Wind patterns are left in the ice pack that covers the Arctic Ocean north of Prudhoe Bay, Alaska
Wind patterns are left in the ice pack that covers the Arctic Ocean north of Prudhoe Bay, Alaska March 19, 2011. Picture taken March 19, 2011. REUTERS
A congressional delegation and the Secretary of the Navy walk around the Seawolf class submarine USS Connecticut after the boat surfaced north of Prudhoe Bay
A congressional delegation and the Secretary of the Navy walk around the Seawolf class submarine USS Connecticut after the boat surfaced through through Arctic sea ice during an exercise near the 2011 Applied Physics Laboratory Ice Station north of Prudhoe Bay, Alaska March 18, 2011. The new digital "Deep Siren" tactical messaging system built by Raytheon Co could revolutionize how military commanders stay in touch with submarines all over the world, allowing them to alert a submarine about an enemy ship on the surface or a new mission, without it needing to surface to periscope level, or 60 feet, where it could be detected by potential enemies. At present, submarines use an underwater phone to communicate with associates on top of the ice or with other submarines, but those devices are little more than tin cans on a string and work only at shorter distances. Picture taken March 18, 2011. REUTERS
A man walks towards snow machines past the plywood hutches and tents that make up the Applied Physics Lab Ice Station in the Arctic north of Prudhoe Bay, Alaska
A man walks towards snow machines past the plywood hutches and tents that make up the Applied Physics Lab Ice Station in the Arctic north of Prudhoe Bay, Alaska March 18, 2011. REUTERS
U.S. Navy safety swimmers stand on the deck of the Virginia class submarine USS New Hampshire after it surfaced in the Arctic Ocean north of Prudhoe Bay
U.S. Navy safety swimmers stand on the deck of the Virginia class submarine USS New Hampshire after it surfaced through thin ice during exercises underneath ice in the Arctic Ocean north of Prudhoe Bay, Alaska March 19, 2011. REUTERS
A helicopter drops off supplies at a remote warming station near the 2011 Applied Physics Laboratory Ice Station north of Prudhoe Bay
A helicopter drops off supplies at a remote warming station near the 2011 Applied Physics Laboratory Ice Station north of Prudhoe Bay, Alaska, in this March 18, 2011 picture. REUTERS
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