Mammoth Iceberg Heads Toward The Australian Continent

A massive iceberg, twice the size of Australia's Sydney's harbor, is making its way toward the continent. Measuring 12 miles in length by 5 miles in width, it is believed to be a piece from the chunk of Antarctica's Ross Ice Shelf that broke off in 2000.

Dubbed B17B the iceberg, currently 1,000 miles southwest of Australia, is the largest chunk of ice that has been seen this far north since the 19th century. Scientists believe that this could be a once-in-a-lifetime sighting for most people.

The B17B, which hasn't melted much during its 10-year life, remained stationary in one area for five years, before being nudged along by strong ocean currents and winds.

While the ice is gradually making its way towards the shore, scientists are confident that it will melt and disintegrate, before it reaches the continent. Even if it does reach the shore intact, it will only cause a minor tremor.

Icebergs form as a result of many years of snow accumulation - As new snow falls over existing layers, it compresses the older layers, which turn to ice. When it gets to a depth of 60-70 meters, it turns to 'glacial ice', which gets pushed out into the oceans from the pressure of their own weight. When they creep out far enough, the end pieces break off, becoming, what we call icebergs.

While it is natural for icebergs to break off, the size of the ones that have been breaking off recently has been very disturbing, and been attributed by scientists to the rising temperatures - a result of global warming.

One of the most alarming has been the disintegration of Antarctica's biggest ice shelf - Wilkins Ice Shelf. Once measuring 13,680sq miles, the shelf has lost over 5,000sq miles in the last two years, and is now attached to the continent by a very thin layer of ice, that could break off any day!

sources: telegraph.co.uk,embraceaustralia.com,independent.ie.com