Birthplace of icebergs
Disko Bay is littered with icebergs as far as the eye can see, the birthplace of which, is the Jakobshavn Isbræ, one of the most prolific tidewater glaciers on earth. 10% of all Greenlands icebergs are made here. Its 5 km wide, 80 metre high face calves some 46 cubic kilometres a year. It surges forward at an average of 20 metres per day, equivalent to 20 million tonnes of freshwater (enough to provide new York City with drinking water for a year).
The fjord is 25 miles (40 km) long. At the glacier it is 500 metres deep, but at its mouth it narrows to 250 metres depth. Here, it’s common to see icebergs towering 20-30 metres above sea level. Some are the size of houses, others are so huge that they lie stuck on the sea bed for years before wearing free and drifting off to wander the Arctic.
It’s hypothesised that an iceberg produced from this glacier sank the Titanic, which is a possibility given the volume and since icebergs beginning here ultimately run south into the Atlantic Ocean. Its an awe-inspiring place.
The nicest way to visit the Fjord is in a small boat. Only here can you get a sense of scale of just how big many of these icebergs are, and see the context of tiny kittiwakes standing on vast giants.
Katak is a little red boat that takes tours into the Fjord. Her wooden sides skim past the brash, bumping and sliding her way past berry bits, giving an up-close-and-personal view of the ice. From her deck it’s possible to collect samples of ice – some clear and others packed with tiny bubbles which crack and fizz when you add water to them. Some of these pieces of ice may be 10,000 years old – compacted under the weight of the ice in the glacier above them.
The Jakobshavn glacier has been studied for over 250 years. Between 1996 and 2005 the rate of retreat doubled, and in 2002 the glacier began to disintegrate into the ocean. The rapid mleting of glaciers has produced a special category of earthquake known as a glacialquake, caused by the ice scraping against bedrock. Jakobshavn was responsible for 11 such quakes during the years 1993 to 2005. The acceleerated rate of glacier retreat will have a big effect on the Greenland ice sheet and , as such, understanding the mechanics of the glacier is crucial to understanding climate change in the Arctic and beyond. For this reason, Ilulissat is often thought to be a ‘ground zero’ in understanding a warming world.