The naturally beautiful St. John’s is the perfect push off for Greenland. Discovered in 1497 by John Cabot the first European to explore the North American coast, Acadia seems at home between two ocean going ferries taking on fuel for the push to Greenland. After one last check of the weather, Acadia set sail mid day on July 3rd passing below Signal Point before turning to the north. Blue skies, southerly wind a gaggle of puffins and a little diesel assist helped push her rapidly along. During the summer months the Labrador Sea and Davis Strait seemed to generate low pressure fronts on a daily basis and Acadia managed to find two of them as we continued on course. The rapid movement of these storms, dramatic shifts in wind velocity and occasional iceberg alert kept everyone on their toes as she moved north.
Acadia reached the south west coast of Greenland mid-day on July 7th exactly 4 days after departing St Johns having covering more than 900 miles. It seemed appropriate that Humbacks would greet Acadia as she entered the protected harbor of Paamiut, a village founded in 1742. After a brief rest and a quick soccer match with local children we headed out, stopping at Friedrickshabb Glacier before overnighting at Ravns Storo, a small beautiful natural harbor and the site of old fishing and whaling stations as well as a monument saluting 8 sailors lost in 1957 with the wreck of HDMS Ternen. Amazingly desolate, the small island was home to at least one family of Arctic Fox who let us know we were not welcome. Heading northwest the next day Acadia stopped at Similut Fjord home of a large glacier some 3 million years old. Absolutely beautiful, majestic peaks surrounded by fog and mist, arctic tern, eider ducks and a white tail eagle that seemed to make everything a bit nervous including those in the tender…big bird. Pushing off mid afternoon Acadia made the last 50 nautical miles in good time before entering the Nukk Kangerlussuaq Fjord and passing just west of the majestic Sermitsiag “Saddle Back” peak. Time for some rest, always required maintenance and preparation for the trip to Ilulissat. Greenland, the world’s largest island covers an area of roughly 2.2 million square kilometers. The ice cap at the center is over 3.2 kilometers thick, covers an area of 1.7 million square kilometers and contains 2.9 million cubic kilometers of ice. The ice cap is the only ice sheet in the Northern Hemisphere that remains from the ice age and at its center the Basel front dates back 250,000 years. Annual snow accumulation is thought to contribute roughly 600 cubic kilometers of ice each year roughly equal to the amount of ice and runoff water entering the sea from Greenland each year. Scientists estimate the cumulative ice loss per year of 220 cubic kilometers. The weight of the ice sheet is so massive it’s believed to depress the earth’s crust some 800 meters. As ice melts, the island rises and this annual elevation change is used to quantify the amount of ice loss each year. Greenland’s ice cap is second only to Antarctica’s estimated to be 750,000 thousand years old and covering an area of 13.5 million square kilometers. Surrounding Greenland’s coast are majestic mountains, some rising 2000 meters and dominating picturesque Fjords. Ice flows gradually from the center of the cap toward the sea but the routes are restricted by these coastal mountains especially in the eastern and southern regions. The area around Disko Bay and the Ummannaq Fjords represents the primary western route to the sea and some estimate half of the total Greenland ice loss occurs from this area. One of the fastest ice streams in the world is Sermeq Kujalleq that terminates in the inner part of the Ilulissat ice fjord. This ice stream moves at an astonishing pace of roughly 40 meters per day, with an estimated 46 million cubic kilometers per year of ice calved into the Fjord. This volume is the equivalent annual water consumption of the United States. The Sermeq Kujalleq ice flow with its high velocity represents a unique opportunity to study Glaciology and interpret the impact of climate change on the glaciers around the world.
The Ice Fjord is remarkable in scope, some three kilometers wide at the glacier face and the ice pushes constantly into the 1000 meter deep Ilulissat fjord. Icebergs as large as 1.5 cubic kilometers calve several times per year. On either side of the fjord are large moraines deposited over thousands of years. These deposits likely continue as a submarine end moraine atop a rock bed across the mouth of the Ice fjord at a depth of approximately 200-225 meters. The large calved ice bergs move down the fjord until the moraine shallows strand them. They rest at the mouth until they melt and float free or are forced out by the pressure of the ice fjord eventually entering Disko Bay and surrounds. It is thought that it takes up to 13 months for the ice to navigate the fjord. The glacier face and ice fjord are a unique natural wonder and for this reason was named a UNESCO world heritage site in 2004. Since nomination the glacier tongue has receded more than 20 kilometers toward the inland ice face and the glacier velocity has almost doubled. The marine ecosystem is strongly influenced by the ice movement through the fjords and into the sea. Subglacial melting adds nutrients to the sea supporting plankton blooms. The cold fresh water from the ice melt also produces upwelling of nutrients from ocean depths. While much remains to be learned about the distribution of marine plankton in the area there is little question to its importance in creating a very rich level of bio diversity. Halibut, Northern Shrimp, Greenlandic Shark, Ringed Seals, Fin, Minke and Humpback whales are common species found in and around the ice at the mouth of the Fjord. As the ice enters Disko Bay it is impacted by western Greenland currents and winds that push the ice to the north. Eventually the icebergs of Disko Bay and the Ummannaq Fjords find their way across to Baffin island where the Labrador current takes the icebergs south along the Labrador Coast to Newfoundland and eventually out into the Atlantic. It is regarded among scientists that Titanic was sunk from a Kanga Glacier iceberg following this route. Entering and exiting Ilulissat is a challenge for vessels like Acadia. The ice pack from the Kangia Glacier and ice fjord is very dense for 10 to 15 kilometers out into Disko Bay. It took Acadia 6-7 hours to travel the 10 kilometers through the ice to the relative safety of Ilulissat harbor when first entering the area. While crawling along and pushing ice out of way, we were regularly passed by Inuit fisherman in their small skiffs and greeting us with a friendly wave. Acadia normally at home at sea was out of her element in the pack ice. The velocity and productivity of the glaciers in Disko Bay and the Ummannaq Fjords is a majestic wonder to behold. There are three categories of ice or icebergs Acadia routinely encountered: snow based, melt water based and basel based. Coming in all shapes and sizes, the term “iceberg” officially refers to chunks larger than 5 meters or 16 feet across. Most icebergs are white in color the result of light reflection on the air contained within the frozen and compacted snow. The snow base icebergs sometimes contain so much ancient compressed air that the water around them fizzes as if it were carbonated. Within icebergs it’s also common to see turquoise or blue ice streaks. These streaks are caused by melt water (free of air) trickling through the glacier and refreezing. Melt water ice is very compacted, hard and can be razor sharp. The sides and base of the glacier that rubs along the wall or floor picks up dirt and rocks. Icebergs can contain this dark or dirty basel deposits. On average about 17% of an iceberg is visible above sea level, hence the infamous term ‘tip of the iceberg’. Icebergs predominately made of basel material or meltwater are more dense and float lower in the water. Pure melt ice is almost translucent and seems to sit on the water with little protruding above the service. Melt water ice represented the greatest hazard to a vessel like Acadia. Arches are also a common and iconic iceberg feature. When looking at an arch it is likely the remains of a vertical hole in the glacier that carried melt water to its core. These holes melt faster than the surrounding ice and expand in the process creating arches or sometimes columns as an iceberg sits in the water melting isn’t uniform, with the ice below the water melting faster than that exposed to air. As the ice melts, the iceberg becomes top heavy and eventually rolls. Icebergs that have rolled will be smooth on top, those that haven’t will often show the jagged layers of ice, a product of the glacier flow lines. While on this expedition we encountered thousands of icebergs, products of the enormous Greenland ice cap and thousands of years of snow and ice accumulation. Breathtakingly beautiful and at the same time concerning as rapid changes and melt rates seem to be accelerating. Reviewing the data collected over the last decade, it’s easy for those on Acadia to see evidence of the dramatic change underway. Scientist at the Arctic Research station and from research institutions around the world studying Disko Bay and surrounding Glaciers are providing tremendous insights into the impact of climate on this fragile ecosystem. We did our best over a short time to experience the wonder of the Arctic and interact with some of the men and women of Greenland. As we depart, touched by the breathtaking beauty and humility of those who are at home here, we are committed to share what we experienced and do our best to raise awareness of dramatic effects we witnessed involving climate change on the marine environment.
by Mark Rohr
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