The Titanic tragedy in 1912 left one enduring legacy: the creation of a group monitoring sea ice in the North Atlantic.

The International Ice Patrol will soon issue its 2018 report tracking the frozen flotilla of bergs and smaller bits — some known as growlers — that sheer off Greenland’s glaciers and drift south into Atlantic shipping lanes and fishing grounds.

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There is every expectation that this year will be as ominous as other recent observations by the Ice Patrol. A warming Arctic appears to have speeded up the process known as glacier calving — the term for ice dropping into the sea from the Greenland ice sheet.

Last year was the “fourth ‘extreme’ year in a row,” according to the Ice Patrol. More than 1,000 icebergs crossed 48 North latitude — roughly the middle of Newfoundland — posing a “particularly hazardous situation for transatlantic shipping,” the 2017 report said.

The good news is that modern mariners have the tools and information to avoid the dangers of ice.

Mostly forgotten now, though, was how another disaster in the ice more than 150 years ago riveted attention to the perils of Atlantic crossings and helped force possibly lifesaving changes to ship design.

This was an age of transition on the seas — the twilight of sail and the dawn of steamships. Vessels of all types were crossing the Atlantic and braving the treacherous Ice Alley off Newfoundland. Fancy steamers were filled with dandies paying a high price for speed and luxury. Packet ships carried cargo and immigrants in grimy steerage compartments to America and Canada.

What they had in common was that the captains and crew had almost no information about ice conditions. This was before the transatlantic telegraph. The only reliable details on Ice Alley came from ships arriving on either side of the Atlantic.

Ice detection was strictly a contact sport. And many, many ships didn’t survive. Shipwrecks in the North Atlantic were so common in the 1850s that they barely merited a scant mention in newspapers when — after months of waiting — it was clear the vessel was lost, sometimes with hundreds aboard.

“Souls gone down in the great deep,” wrote the Pittsburgh Gazette in 1856 in a rare lament about the callous views on shipping disasters, “without leaving a ripple on the surface of the ocean, or causing a ripple on the great surface of society.”

Earlier that year, a three-mast packet ship, the John Rutledge, left Liverpool. Aboard were more than 120 immigrants bound for New York, mostly Irish but some Scots and English. The captain, a Cape Cod seaman named Alexander Kelley, had a crew of about two dozen. In the cargo hold was crockery, salt and coils of rope.

Sketchy reports of heavy ice were just reaching Liverpool. Some captains said they had never seen Ice Alley so filled with huge bergs, growlers and small but still menacing fragments called bergy bits.

Still, the John Rutledge headed out. So did dozens of other ships in January 1856. Among them were two New York-bound clippers leaving England and the steamer Pacific, which left Liverpool a week after the John Rutledge.

The westbound crossing was brutal from the beginning. The hatches to steerage were often battened shut on the Rutledge, leaving the immigrants closed off for days in a heaving wooden cavern of screams, prayers and unfathomable stench. The top bunks were most coveted. At least there was no one above them spewing their seasickness on their heads.

On Feb. 19, the John Rutledge slipped into thick fog near the edge of the Grand Banks, about 350 miles southeast of Newfoundland. Suddenly, a sharp-edged berg gouged a hole in the ship’s hull. Crews tried to plug the leak with cargo.

It was pointless. The John Rutledge — like nearly every American-built vessels in those years — had an open hull design, meaning no water-blocking compartments. Once a hull was breached, the water was free to flood the length of the ship.

The Rutledge was going down fast. Kelley ordered the lifeboats lowered.

All five lifeboats got off. But it was not enough. At least 30 people, including the first mate, were left on the deck to be swallowed by the Atlantic.

Thirteen people were on the last lifeboat. There were three crew members, including a 22-year-old sailor from a prominent Massachusetts maritime family named Thomas W. Nye. The rest included passengers: the first mate’s wife, and nine immigrants that included a small girl and two young boys.

They had only one demijohn of water, about a gallon, and about six pounds of cement-firm biscuits known on land as hardtack. One by one, they died. Some from exposure. Others from the horrors of drinking seawater — organ failure, delirium, madness — once the demijohn ran dry.

After nine days, only Nye was left, surrounded by four frozen bodies. He was too weak now push them over the side.

Remarkably — and probably only hours from death — a ship spotted Nye’s lifeboat. The Germania, sailing from France to New York, should not have even been there. It left Le Havre just before the ice reports grew so alarming that shipping lines set more southerly routes.

Nye rescue was a brief sensation. It was exceedingly rare for anyone to be plucked from a North Atlantic wreck. And rarer still was the survivor to be from a notable family line that had whale ships, merchant vessels and illustrious figures that included a U.S. envoy in China.

The attention on Nye also helped spur one other important change that possibly saved countless lives in the future. Groups pushing for more safety on the seas used the John Rutledge and other ships lost in early 1856 to bolster their demands for rules requiring watertight compartments on U.S. vessels.

The influential U.S. Nautical Magazine and Naval Journal used the John Rutledge sinking — and Nye’s widely reported accounts — to try to shame shipowners accused of avoiding watertight compartments because of higher costs. “[They] are computing the advantage in dollars and cents; a few hundreds, or even a few thousand dollars, expended in adding security to human life, is of little consequence” to their bottom line, said an 1856 essay in the journal.

In coming years, more American shipwrights began to make the potentially lifesaving design modifications. It finally took the loss of the Titanic, decades later, to force sweeping rules for bulkheads and water-blocking chambers in all U.S. ships.

All told, more than 830 people were lost in early 1856 — among the most tragic season in North Atlantic shipping for decades to come. Gone were the John Rutledge, the two clippers and the steamer Pacific.

Only Nye survived.

Brian Murphy, a Washington Post editor, is the author of the recently released book on the John Rutledge sinking, “Adrift: A True Story of Tragedy on the Icy Atlantic and the One Who Lived to Tell About It.”