Rough weather this morning. We’re just under halfway across the Drake Passage, which separates South America from Antarctica, and the sea is handing us a whipping. Winds up to 55 knots and gusts up to 100 have piled the sea into an endless stampede of rolling swells.
The swells rise 45 feet. The ship pitches and creaks as its bow bucks over the top of one wave and plunges down to the belly of the next. Viewed through the round windows at water level, the world outside resembles the churning contents of a washing machine
As I step out of bed, my bare feet slide across the tilting floor—right, then left, then right again. I resort to sitting on the floor as I gather my things. Showering while holding on white-knuckled with one hand, lathering with the other, and bracing both feet evokes a feeling of absurdity—an attempt to maintain normalcy when things are in fact far from normal, like awakening into an episode of Laverne & Shirley or I Love Lucy. Except in this case the hanging on isn’t just funny; it’s all that separates me from serious injury.
Downstairs, the labs sit deserted—laptop computers bungee-corded to counters, monitors bobbing, and a few chairs capsized on the floor. Motion sickness pills or not, most people haven’t ventured far from their beds today.
Pilots have eased the Nathaniel B. Palmer’s throttle back from ten to six knots and turned her into the wind. That adds a few hours to our dash for the shelter of the Antarctic Peninsula, but it also eases the punishment being heaped on both man and machine. With the course deviation calming things just a tiny bit, crew members hurry to secure a 20-foot rescue speedboat—hanging on our starboard side along with lifeboats—that clanged ominously through the night. Mechanics check the two helicopters. Even with them tied down, the hanger affords their blades only four inches’ clearance above. A stray bounce could damage a blade, ground a helo, and prevent our scientists from getting to the glaciers they hope to study.
Today separates those of us with sea legs (and stomachs) from those without. And the ship, with its decks stacked one atop another, has become a Jungian metaphor: The higher you climb above the water, the worse the side-to-side motion becomes. The stronger your stomach, the higher you can climb. I climb six flights of stairs, slowly, to the highest level—the bridge. Four of our scientists gaze out the panoramic windows, chatting serenely about the decomposition of whale bones on the seafloor. I lie flat on the floor to steady my stomach, then beat a rapid retreat downstairs.
In the galley a light fare of sandwiches is served for those with the stomach to eat. I pull aside Gary Talbot, one of the mates responsible for piloting the Palmer. “You’re really not taking anything for seasickness?” I ask. “No,” he says, “just a BLT.” His nonchalance says more than his words.
By 10 p.m. the seas settle down slightly, and the Palmer reaches a milestone: We’re now officially outside Argentine waters. We can begin collecting scientific data. The multibeam sonar is turned on. An XBT (expendable bathymetric temperature probe) is fired like a harpoon into the water. It will tell us the temperature of the water as it sinks to a depth of 6,000 feet, before falling to its permanent resting place on the seafloor.
A map on a computer screen displays our current position, and the multibeam sonar (multibeam for short) paints a swath of yellow-green onto the map—with different colors representing different depths in the undulating terrain below. From where we stand, the seafloor is 12,000 feet down.
The multibeam will map the seafloor for the rest of our journey. These are some of the least known seas in the world. Knowing the seafloor is crucial for understanding Antarctica’s glaciers. Many of them rest on beds that lie below sea level—in some cases up to 6,000 feet below. Map the seafloor around Antarctica and you can see a bit of history: troughs carved by the glaciers as they expanded out to the edge of the continental shelf during dozens of ice ages over the past 30 million years.
Those same grooves will play a part in modern history as temperatures rise. They're an Achilles’ heel for many of Antarctica’s glaciers, providing a path for warm, deep water from farther north to follow to the glaciers’ feet. Some of the most worrisome melting is already happening far below sea level and out of sight.
We should see our first Antarctic islands tomorrow night—hopefully a smoother ride than we’ve seen so far. From there on, the ship will become busy with science. Come round again, and we’ll share some of it with you.
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