How does ice make your life more difficult?
In the open ocean, if something goes wrong, we can always make a vehicle buoyant, so it comes to the surface. You can locate it using a radio frequency beacon, and then you can drive your ship to it and pick it up. Under the ice, that doesn’t work, because if we were to shut the vehicle off and let it drift to the surface, it would come in under some ice, and we may not be able to recover it. And we have a saying in the underwater world: The number of recoveries should equal the number of deployments.

So what kind of adjustments do you have to make for the Arctic Ocean?
The first thing we have to do is cut a hole in the ice to drop the vehicles in to do their mission. But while a vehicle is under water, the ice at the surface will drift or even close up again. If something goes wrong unexpectedly, the vehicle will turn itself off and come up anywhere.

So our operational scenario says that once a vehicle has completed its mission, it will rise to about 200 meters from the surface. We will communicate with it by transmitting and receiving acoustic signals. We’ll make another hole in the ice, tell the vehicle where that new hole is, and tell it to swim to the new hole for recovery. In a worst-case scenario—for example, we can’t talk to the vehicle, or it dies, or something bad happens to it—it’ll still float up toward the surface and, we should be able to locate where it is under the ice and make a hole and try to pull it out that way.

What will the underwater vehicles look for?
At first, plumes from hydrothermal vents. They are a little bit like smokestacks for factories. The smokestack has a diameter of only a few meters. But as it spews out smoke, the smoke usually rises up in a straight line vertically, and then it starts spreading out horizontally over large, large areas. Hydrothermal vent plumes work similarly and can lead us back to their source.

These vehicles have never been used before—are you optimistic?
If we were to propose using standard deep-submergence vehicles for this Arctic expedition, people would say, “No way. It’s too risky.” So we proposed something new—based on our previously successful design for an underwater vehicle. We think it will do the job. I hope it’s not a sacrificial lamb.

So, yes, it’s very risky. Yes, we have a strong chance of failure, where failure may be defined as losing a couple of vehicles and not getting enough data. But I believe we have a strong chance of success in terms of actually going out and learning something about these hydrothermal vents, and maybe sampling some of them. Given the risks and the potential returns, we felt that this is worth pursuing, and that’s what we’re doing.

If we didn’t take risks, we would not make huge leaps.

You know, even in open water it often it takes people months to find vent sites. Trying to do this under ice in the Arctic is way, way harder. So stay tuned.

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