The desolate landscape of the Arctic icecap is about to change, at least temporarily. First, one hears the noise, and then something rises out of the ice.
On the top of the world, 200 miles north of Alaska, it's a nuclear powered attack submarine, the USS Annapolis, crashing through three feet of ice. This is a military exercise in an area that may hold a quarter of the world's undiscovered oil. It's a mission that has now become critical because of climate change.
For the first time, the Navy has allowed a network television crew to see its ICEX exercises, which it conducts every two years. The purpose is to prove the Navy can operate in this unforgiving environment to protect the national interests.
Those interests could be threatened because the Arctic ice is thinning and receding more every year, possibly allowing more access to this now frozen body of water.
A new National Science Foundation report suggests that the melt is so quick that the Arctic could be devoid of ice in the summertime by 2040. That could start a "gold rush" of sorts for all that "black gold" under the Arctic's seabed.
"One expects to see more military exercises here, but [one] could, you know, eventually, if our fears come to roost, even [see] commercial transportation here," U.S. Energy Secretary Steven Chu told ABC News moments after he stepped onto the ice from the Annapolis.
"This is a very difficult environment for the submarines to operate in," said Navy Capt. Gregory Ott, standing in a plywood hut that served as his headquarters for the exercises on the ice.
A crew of 50 scientists and sailors lived for a month in the temporary "ice camp" to work with the subs.
"The ocean here is almost the upside down of oceans elsewhere. Here, it's actually colder near the surface where most oceans are warmer near the surface," Ott said.
That temperature difference affects buoyancy, only one of the challenges the submarines face in the extreme Arctic.
So, when the commander of a nearly $1 billion submarine ordered his crew to surface, nothing was routine.
"It was the most nervous I've been in my career," said Cmdr. Michael Brunner in a chat 350 feet below the surface of the ice in the Annapolis' control room. "I don't get less nervous with each one. We've done five vertical surfacings and [with] each one, the Arctic environment throws a little curveball at us."
Brunner's sub had just been retrofitted with the latest sonar and communication gear. But all the technology in the world doesn't guarantee an accident-free surfacing.
During its time in the Arctic, the Annapolis tried out its new communication system. (It sounds a bit like an old dial-up modem.) The crew sent messages to the surface and to the USS Helena, another sub in the area for the exercises. And the crew practiced firing torpedoes.
"Weapon in motion," one of the torpedo room crew members shouted as a massive weapon was loaded into a tube.
Up in the control room, the commander ordered his crew to fire on a fictitious target.
"Shoot tube 4. Fire tube 4. Torpedo course 0-5-1," were the rapid-fire orders in the control room.
The salinity of the water under the ice is much different than open water; torpedoes "swim" differently there. The test firing was repeated often. But those were expensive weapons even if they weren't armed.
Up on the surface, each torpedo was recovered. The crews, some from the Applied Physics Lab at the University of Washington, had developed a melting tool to help them. When they found the torpedo, which transmitted a signal, the melter was placed over the ice and heated water helped "cut out" a cylinder of ice. The plug was pulled, divers jumped in to hook up chains, and a helicopter then pulled the torpedo through the hole.
Operations in the Arctic are key for the Navy.
"So you can imagine if the ice recedes, it could become a major shipping route," said Ott. "And the United States wants to be able to operate in that shipping route as we do in any place else in the world."
The countries around the Arctic want to do the same, especially considering the large amount of oil, gas and minerals believed to be below the seabed and the fishing grounds that would be opened up as well.
Already, the Russians have placed a flag on the seabed, at the North Pole, claiming it as their territory. Not surprisingly, the Russians were watching every move of the U.S. Navy during its exercises.
"I would expect the Russians would watch us via satellite or however they do that as they probably always do. I'm sure they are watching us right now as we speak," Ott said as he walked the ice camp with ABC News bundled up in a parka with wind chill temperatures about minus-50 degrees Fahrenheit.
Ott also scoffed a bit about a news report that the Russians are putting together an Arctic Navy.
"You know, we already have an Arctic submarine fleet," he said. "So, I would say they are probably a little bit behind the power curve."
The scientists and sailors who are flown out to the "ice camp" live in plywood huts that were prefabricated in Seattle and assembled on the ice. Kerosene heaters keep the huts comfortable, but nothing there is really warm. There is no running water and the outhouses are, well, unheated. But the three cooks in the mess tent keep the crew fed, and there is always coffee available.
One job on the surface is to give the sub a target to surface through.
"They have shoveled the snow off the ice; the sunlight comes through much clearer," said Lt. Cmdr. Chris Hover, the executive officer, looking at a video screen.
The Annapolis has one camera. It points upwards, and even 350 feet down the ice on the surface can be seen, as well as the spot where the snow has been shoveled.
"We want to pop up right there on the center of the X," said Hover.
But the surfacing will be a bit tricky. The spot they were working had become unstable.
"There were times when I surfaced one day, surfaced less than 24 hours later and the salinity and the temperature profile that we came through was completely different, causing us to change the way we did it from just 18 hours before," said Cmdr. Brunner.
The new post includes plenty of dangerous ice. The sailors call them keels. They are pieces of jagged ice that can reach more than 100 feet below the surface.
"Listen up," Brunner said into the sub's intercom microphone. "We need to make sure we're extra vigilant during this attempt. We are going to be threading the needle into a feature that's only 150 yards wide."
He said it would be like parking an S.U.V. into a parking space marked for a compact car. And it was clear the commander and the crew were a bit anxious about this surfacing.
"Vertical surface, vertical surface, vertical surface," went the call over the intercom to the crew.
It was difficult to tell, but the sub was rising. On the monitors, the numbers were getting smaller. Two hundred feet ... then we passed the 100-foot mark.
As we got closer, the officers in the control room were in full concentration mode. You could see the tension on their faces. Chief of the Boat Tomas Garcia started calling out the depth.
"Twenty-five feet, 10 feet," Garcia hollered out. "Five, 4, 3, 2, 1."
Then the officer of the deck yelled, "full blow." The ballast was blown so the sub would break through the ice. It isn't a crashing feeling, but the contact with the ice did shake the sub a bit. Within moments, as more ballast was blown, the sub leveled off, having broken through more than two feet of ice.
Plenty of smiles and deep breaths were taken in the control room. The sub was safe. Cmdr. Brunner even got a bit emotional as he congratulated his men.
"This will be our last vertical surfacing in the ice camp," he said. "I just want to let everyone know, you all have exceeded my expectations throughout this ice camp evolution. We trained hard. We had a rough road to get here. You have done an outstanding job."
It took nearly an hour for crews to cut away the ice covering the hatch using chainsaws. Back on went the parkas as people ventured out of the sub and back onto the ice.
The Annapolis would be leaving later in the day with some experiences that would be shared throughout the Navy.
"I definitely think some of the tactics will change, especially in the weapons deployment area, based on the results we've seen," said Brunner.
The Navy will need to hone those tactics as the ice continues to melt, opening up this vast wilderness to exploration and a possible 21st-century "black gold rush."