Position: Anywhere at Sea
Perhaps the greatest challenge for ocean-going seafarers is the convoluted nature of weather and waves. Wind, air pressure, temperature, currents, land masses, the gravitational pull of the moon and the contours of the seabed all mix in ways that confound simple rules of thumb. With so much complexity, even trans-Atlantic skippers fall back on sayings like, “Red sky at night, sailor’s delight. Red sky in the morning, sailor’s warning.” Thanks to new technology that is changing.
Predicting the behaviour of the world’s oceans and making those predictions relevant to something only a few times larger than Aleta has been the goal of weather forecasters and shipping magnates for centuries. Today, just as in the past, the investment in oceanic forecasting is driven by commerce. Global climatology is interesting, just not as interesting as making sure all that oil and wheat gets where it’s going. That’s why NOAA (America’s National Oceanic and Atmospheric Administration) falls under the Department of Commerce, not the Department of Climate Change*.
Data, Data, Data
Throughout the 20th century our knowledge of weather patterns grew exponentially. The inventions of weather observation balloons, satellite imaging, airborne radar, and of course computers all played significant roles.
More recently satellite altimeters and flotillas of buoys deployed around the world feed a constant stream of data about sea and weather conditions directly to supercomputers. The computers crunch the data and make predictions. Scientists review the predictions and, based on what actually happens, tweak the computer’s algorithms in ways they hope will improve weather forecasting. All of which should improve the safe passage of goods. And, by proxy, Aleta.
Rogue Waves
Now let’s introduce rogue waves into this rough mix. Long considered the stuff of sailing folklore by landlubbers, a rogue wave is a massive, unpredicted wave capable of swallowing up even the biggest ships. Unlike tsunamis, rogue waves are not the result of earthquakes. They form by nature’s strange alchemy, bringing together the forces of wind, currents, and other waves and building them into monsters. Proof of their existence finally occured in 1995 when an 85-foot wave crashed into the Draupner oil platform off the coast of Norway. The event was scanned using a laser thingamajig which gave the observers all the credibility they needed.
Scientists now believe rogue waves happen all the time. At least once a day. Somewhere around the world. Albeit randomly. And, like the sound of a tree falling in the forest, there may be just enough sensors around the world to tell us if these giant waves indeed make a sound when they crash forwards. (That’s sounding, surely. – ed.) There is even a definition for a rogue wave: a wave at least twice the height of a formation’s “significant wave height,” or the mean of the largest one-third of a wave record.
Now that the threat of rogue waves has moved from the domain of superstition into the realm of data crunchers, and their threat is quantifiably big enough, the invisible hand of commerce is willing to throw wads of cash at making reliable predictive computer models of these elusive beasts.
Artificial Intelligence to the Rescue
Given all the complexity, meteorologists and climate scientists are turning to Artificial Intelligence (AI) for help. Dion Häfner and a couple of his closest friends gathered 1.4 billion wave measurements and fed them into a neural network and applied some fancy math. Given AI’s superior pattern matching abilities, their model, “…reproduces known behavior, generates well-calibrated probabilities, and achieves better predictive scores on unseen data than current theory.” You can read all about their findings here: Machine-guided Discovery of a Real-World Rogue Wave Model
Action Stations!
Cool! Knowing that a giant wall of water pops up daily someplace in the world is a start. But since the only identified point on Earth where rogue waves occur regularly is off South Africa, more work is needed.
More importantly, what might Aleta’s skipper do about one? (Hint: “Not a damn thing!” and “Drain the rum supply!” are not the sort of actionable recommendations we have come to expect from this august journal. Although they will do in a pinch.)
If you are presented with a rogue that isn’t named Bernie, you will, in all likelihood, already be in your foul weather gear and dealing with the storm raging around you.
Here’s a short checklist if a behemoth comes knocking:
- Turn on your GoPro camera.
- Batten down the hatches – again!
- Plug your Dorade vents.
- Start your engine.
- If you heaved to and can safely strike your sails do that.
- Turn your bow directly towards the wave and go below.
- Crawl into a berth and cover yourself with pillows.
- Crack open the rum.
- Take a breather – it should be over in a few minutes.
Once the wave passes, go above decks and see how much of your rigging is left. Call your insurance broker and take another swig of rum. You deserve it.
More
This chap does a nice job explaining rogue waves:
And here is a fiendishly useful book: Introduction to Oceanography
* Which isn’t thing, by the way.