Fatal Voyage: The Titanic

This image depicts an interesting iceberg phenomenon:  Most of an iceberg's mass exists below the waterline.  Image online, courtesy U.S. Coast Guard.

As Titanic made her way from Queenstown to New York City, she would steam through the North Atlantic. As she neared the Grand Banks, she would skirt a dangerous area called Iceberg Alley.

Where does this ice originate? Greenland, which is a kind of huge iceberg factory, has about 20 iceberg-producing glaciers along its coast. Glaciers are formed from thousands of years of accumulating snow.

After the snow compacts, forming glacial ice, it begins to slowly move as a kind of viscous ice river. Sometimes pools of melting glacial ice form beautiful deep-blue glacial cirques.

The ice river continues its slow trek to the ocean.  Huge portions of ice then "calve," or break away at the water’s edge. We call those breakaway sections of former fresh-water glaciers "icebergs."  Watching (and hearing) an iceberg calve is an amazing event.  

Once icebergs have broken away, they can become part of "ice packs" which form during the North Atlantic's "ice season."  The ice season typically lasts from February 15 through July 1st. 

Some of the biggest icebergs in the world are formed in Greenland. Ilulissat, the most active glacier in the northern hemisphere, sends about twenty million tons of ice into the sea every day. Some bergs are 100 meters high and are still moving south in April.

Although these mountains of ice are buoyant, fully 7/8 of their mass is underwater. A ship, steaming at top speed directly south of Iceberg Alley during the month of April, could reasonably be assured of a potential disaster.