Ernest Shackleton dreamed of crossing Antarctica. The obvious place to do that was at its narrowest point. That meant pushing south into the Weddell Sea, a giant bay well over a thousand miles across hemmed in on three sides by the Antarctic continent, the Antarctic Peninsula which reaches up towards Cape Horn, and the series of islands, like the South Orkneys, that help to close it off from the South Ocean.
Shackleton’s plan was to land on the southern shores of the Weddell, then cross overland, via the Pole to the Ross Sea on the far side. Few ships had ever before penetrated into the Weddell. The first was Mr. James Weddell himself, a Scottish seal hunter who in 1823 sailed deep into it, in what turned out to be a peculiarly sparse year for sea ice.
Victims of the Weddell Sea
In 1903 and 1904 a Scottish expedition led by William Bruce aboard Scotia learned valuable information about the Weddell but beat a hasty retreat as the ship was threatened with entrapment in the ice.
A Swedish ship, Antarctic, was crushed and sunk by that same ice in 1903, and the German explorer Wilhelm Filchner was frozen in the ice for 8 months during the 1911-1913 Second German Antarctic Expedition. The spring thaw released Filchner’s vessel, Deutschland, but not before the crew’s morale had broken down. A dark winter entombed in the ice had shattered their cohesion.
The Weddell was clearly a hostile place, but Ernest Shackleton was not put off. He gambled that he could get as far south as Filchner and then make a dash across the continent to a ship on the other side. The gamble failed, spectacularly. The Weddell, one historian has written, was “the most treacherous and dismal region on earth.”
On the trail of Shackleton
I have just entered the Weddell Sea aboard the South African icebreaker Agulhas II. By coincidence, we saw our first iceberg fairly near where Shackleton saw his after leaving South Georgia. He called them ‘growlers’, big chunks that have broken off the ice shelf and drift north, pounded by wind and sea until they melt completely. During the course of that terminal journey, they are still big enough to smash the hull of any wooden ship that sails into one.
Our ship picks them up on the radar and avoids, but Shackleton had a lookout aloft, staring into the murk to try and spot them. “The weather was hazy,” he wrote, “and we passed two bergs, several growlers and numerous lumps of ice… Large numbers of ‘bergs, most tabular in form, lay to the west of the [Sandwich] islands… The presence of so many bergs was ominous.”
The whalers he had talked to in South Georgia, the old sea salts who knew this stretch of ocean better than anyone alive, had advised him not to head south: the Weddell was full of ice, better to leave it to the following year. Shackleton ignored them.
A continent of ice
Sea ice forms on the water’s surface when the temperature reaches -1.8°C. In the winter, the Antarctic continent is surrounded by typically 19 million sq km of ice. In the summer that falls to 3 million sq km. But much of that ice is in the Weddell Sea. Its peculiar geography means that a current or ‘gyre’ drives the ice clockwise in a churning mass. Ice can survive a summer or even two or more.
To this day, the Weddell Sea can prove difficult for modern vessels to traverse. When the ice is dense, ships have to ‘puddle hop’ between patches of navigable water amongst the thick ice. Even into the 21st century, oceanographic exploration of the Weddell Sea has been less thorough than in other polar regions around the world, given its extreme weather and icy conditions.
It’s amazing Shackleton got as far as he did. Slowly, painfully, he threaded Endurance through the pack ice, looking for what he called ‘leads’ – passages of water through the ice floes. He headed east to try and get around the big cul de sac of ice against the Antarctic peninsula in the western Weddell.
Shackleton made it to the coast, but rather than land here, and face a much longer drag across the ice, he continued south hoping he could get to a landing point that Filchner had discovered on his expedition. He got to within 200 miles.
A north-easterly gale pounded the Endurance in mid-January 1915. They had to hide behind big icebergs for shelter, but the gale had the effect of driving thousands of square km of ice up against the continent and trapping Endurance within it. By the evening of 18 January, they were stuck fast. As one of the crew commented, “like an almond in the middle of a chocolate bar.”
They were now at the mercy of the ice.
Read more about the discovery of Endurance. Explore the history of Shackleton and the Age of Exploration. Visit the official Endurance22 website.