Three hours later the silence of the crew is broken by the radio. Something is wrong, Okafor doesn't usually initiate the check in.

"Captain Nakamura? Do you copy?"

"What is it, Okafor?"

"I picked up a mayday, sir. From the team out in Masi."

I glance at Fischer as she checks the map.

"It's maybe a hundred kilometres to the north-east, Captain."

Too far for my liking, but I keep that to myself. Fischer doesn't need confirmation from me, she is already turning.

"What did they say, Okafor? What's going on there?"

"I don't know, sir, there's no response now. They said something about... something attacking them."

"Something?"

"I am trying to contact them, sir, but no luck yet."

"What channel are they on?"

"Thirteen sir."

"Right, let's all switch to thirteen. Keep trying to raise them."

"Yes, sir."

We can't say it out loud, we're on the open radio now, but I can see the nervous faces showing what I am thinking. Were they attacked by something, or someone? I don't know which is worse. When a station fails or runs out of resources, it leaves desperate survivors behind who have to choose between dying, and trying their luck at another station.

"Masi station," the radio cracks, "do you copy?" No answer.

The barren desert eases past the windows as we make our way towards the stricken base. I can feel my breath becoming deeper, heavier. I'm always the first to run out.

"Let's change our oxygen tanks before we get there."

The rover slows to a halt, and we climb out and change the tanks. The empties are attached to the filters, though I can see from the gauges that the Norwegian brothers still had nearly a quarter left.

I watch Fischer checking the equipment, visibly struggling to crouch lower. She's nearing fifty. I worry about her, but I can't tell her that.

My eyes swing around to the west, to the ridge stretching in the distance. Behind it lies the valley I had planned to check. Some lost grain of hope suggested we might find water deep below the bed where the glacier melted into the ground some decades back.

"You two ever been to Masi?"

The brothers shrug as they glance at each other.

"Might have passed through at some point."

They grew up in Oslo in the '40s, back when winter still stretched that far south, but their safe-haven didn't last much longer. The barren deserts from the south swallowed it within a decade.

"Masi station, do you copy?" Okafor is still trying to raise them, but there has been no response.

"All set, Captain," says Fischer. "Let's move."

It's not long before we summit a ridge, allowing us to see Masi up ahead. Old roofs peek through the red sands. The steep angles were designed to avoid too much snow building up and causing damage, not to protect them from being swallowed by a desert. The research station is situated on the rise overlooking the town and, importantly, above the encroaching sand. But even from here, we can see the damage.

"Orders, Captain?"

"Approach with caution."

Fischer turns to me with a look suggesting she has a snide remark, but she keeps it to herself and advances towards the station. She stops around ten meters from it, watching for any movement. There is still no response on the radio.

"Let's go take a look."

Some of the glass panes are shattered, and the airlock door is broken. It's bent outwards, as if they tried to push it open with a vehicle. But there are no tyre tracks in the sand, and within the bay an old car is parked in the only space. It's unsuitable for this terrain, and it probably stopped working a long time ago. Maybe they did get away, but I can't shake the feeling that this team has been trapped here, possibly for years.

Inside, there is evidence of a struggle, but of the occupants themselves there is no sign. No bodies, no blood. No life.

"I'm going to look around outside. Find anything we can use. Or eat."

We've stocked our shelves with supplementary paste we've found in the deserted towns over the years, but it won't last forever. When people fled northwards, they must have thought there would be something better to eat there. Nobody wanted the paste, not when they realised what it was made from. We crossed a threshold in the '30s: not enough food to eat, and too many mouths to feed. What was once a horrific idea soon became a well-organised activity overseen by powerful governments. The cull affected poorer nations first, but it was naive to think it would end there.

"What do you think these are?"

Fischer had followed me outside, and is pointing to two holes in the ground beside the station. They're big enough for people to crawl into. And they're deep.

"Underground storage, perhaps?" I suggest.

"Or a hiding place."

"To hide from what?"

"I'm not sure, Captain, but they were attacked by... something. Maybe..." she trailed off, and I didn't persist.

"Eirik, Anders, did you find anything inside?"

"Food stores are still here," replied Anders. "If they evacuated, they didn't take the stocks with them."

I'm still staring at the entrance to the tunnel at my feet. I can't see how deep it is, or where it goes. I don't like this at all. People can be innovative in their desperation. I'm not sure I want to know what's down there.

"Take what you can and let's get out of here."

Fischer nods her agreement, and returns to the rover with the brothers close behind, loading boxes into the back of the vehicle.

The electric motors begin to drive the wheels, and we're soon on our way. Apart from radioing in to Okafor to let him know we're on the move, there's little conversation.

Before long, I notice Fischer is driving faster than usual.

"What is it, Leigh?"

She sends me a nervous glance. I can see she is debating lying, and I shake my head.

"Warning light, Captain. The air filters."

I swing around to see the four oxygen tanks connected to the air filters. They should be at least half full by now.

"What's wrong with them?"

"I don't know, Captain. But I'd rather make it back to base then waste time trying to fix them out here. I might not be able to. If I drive a little faster, we should be back before our tanks are empty."

Before their tanks are empty perhaps. Mine is always depleted first.