In my new novel, The Shantyman, the clipper ship Alhambra nearly collides with a massive ice island.  From Chapter Nine:

In the forenoon watch came the cry, “Ice, dead ahead.”

It was my watch below, but I jumped up with the rest and headed forward, expecting to see an iceberg. Instead, I only saw white. It took me a few minutes to realize that I was wasn’t staring at fog but at the white face of an ice cliff, the sheer side of a drifting island of ice, rising close to one hundred feet high. The massive floating island looked as tall as the masts and stretched out to port and starboard, disappearing into the fog on either hand. And we were sailing straight for it

The event in the novel was based on various accounts from clipper ship voyages from the 19th century.  By using Matthew Fontaine Maury‘s Wind and Current Charts  as well as his Sailing Directions, clipper ships of the day had been making faster passages around Cape Horn. Maury’s charts and sailing directions did, however, send the ships farther south, closer to the ice and icebergs. The clipper ship John Gilpin sank after hitting an iceberg in 1858 while just a year later, the clipper Fleetwood met the same fate. Numerous ships were also damaged by ice but made it to port. Every year, ships simply disappeared rounding Cape Horn, so it is unknown whether they hit ice or were overwhelmed by the seas.

These days scientists refer to a floating island of ice as a “tabular iceberg.” The 19th century sailors described  these monsters as being from a few miles to up to 100 miles long. Some have thought that the sailors may have been exaggerating, telling sea stories.  Scientists have only been able to track large tabular icebergs for the last 25 — 30 years, following the the advent of satellite photography, yet even in that relatively brief period, it is clear that the clipper sailors were not exaggerating what they saw.

In March 2000, an iceberg broke off of the Ross Ice Shelf in Antarctica. Called Iceberg B-15, it was approximately 295 kilometres (183 mi) long and 37 kilometres (23 mi) wide, with a surface area of 11,000 square kilometres (4,500 square miles) or roughly the size of the State of Connecticut. B-15 was also a half mile thick and was estimated to contain an amount of freshwater equivalent to the average annual rainfall on the entire land surface of Earth. B-15 was the largest iceberg ever found by the U.S. National Ice Center, but since the center only began tracking icebergs about 25 years, it is possible that even larger tabular icebergs have existed in the unrecorded past.

Scientists say breakoffs of monster ice islands like B-15 should occur about every 50 to 100 years. But a growing number of researchers fear global warming may be playing a role in speeding the breakup of Antarctica’s ice shelves. If that is indeed what is happening it could be vary bad news for the 44 percent of humanity who live near the ocean.

A recent study suggests that the Totten Glacier of East Antarctica is melting far faster than had been previously thought.  Why is that a problem? As reported by the Washington Post:

That’s alarming, because the glacier holds back a much more vast catchment of ice that, were its vulnerable parts to flow into the ocean, could produce a sea level rise of more than 11 feet — which is comparable to the impact from a loss of the West Antarctica ice sheet. And that’s “a conservative lower limit,” says lead study author Jamin Greenbaum, a PhD candidate at the University of Texas at Austin.

Gigantic Tabular Iceberg from Antarctica