요쿨살론(Jokulsarlon. Jökulsárlón) 안내. 아이슬란드(Iceland)

요쿨살론(Jokulsarlon. Jökulsárlón) 안내. 아이슬란드(Iceland)

The Jökulsár lagoon

The white cap of Breiðamerkurjökull glacier dominates the lagoon and its icebergs. The lagoon is steadily expanding and in 1998 it had a surface area of 14.8 ㎢ and a maximum depth equal to 190 m. From 1890 to 1998, the glacier retreated about 3.8 km and is still retreating. The icebergs break free from the glacier dege and are carried by the current towards the river mouth, until they strand on the bottom. only one tenth of the iceberg's mass is visible above the water-surface. Tidal currents move the icebergs back and forth, causing them to scrape the bottom of the river. Winds and tides erode the icebergs until they are small enough to float to the sea. Most icebergs are milky white, but some have a a bright blue colour, caused by the interplay of light and ice cristals. Seals are often seen swimming in the lagoon or lyng on icebergs. Shoals of herring or capelan are sometimes carried into the lagoon by the tide, making a least for the birds.

Coastal erosion

In 1967 a 108 m long suspension bridge was built across Jökulsár river. At that time the distance from the cost to the bridge was 500 m but in 1998 the distance was 350 m. What was happended ? The shape of the coast in the beginning of last century was influenced by the fact that Jökulsár river carried substantial amount of sediment to the sea (9 million ㎥/year). The coast had advanced until currents, generated along it during storms, were able to carry the sediment load of the river to both east and west of the river mouth. Since the glacier started to retreat and the lagoon emerged the sediment load to the sea has been reduced and the shape of the coast was not in equilibrium with the currents. The currents are still eroding sediment from the coast but almost no sediment is carried to the sea by the river. The coast will therefore erode until a new equlibrium is reached. The coastal erosion has been 750 m in the period between 1904-1998 or 8 m/year on average. This erosion threatens the road (Route one) on Breiðamerkursandur.

Breiðamerkursandur  =  broad forest sand

Formation of the lagoon

At the time when the first settlers arrived in Iceland, the edge of Breiðamerkurjökull, an outlet glacier of the great glacier Vatnajokull, is thought to have been about 20 km further north than it is now. The climate began to cool in about the year 1200, the cold spell reaching a peak in the period 1600-1900, which is sometimes known as the "Little Ice Age". As a result, the glacier advanced until about 1890, reaching a point only about 1 km from the coast at Jökulsár river. The eastern part of the glacier eroded the sediments of Breiðamerkursandur to a depth of up to 300 m below sea level, the sediment being carried forward by the river Jökulsár. Without the river the glacier could not have eroded such a deep basin, because it is the river that carries the sediment to the sea.

The warm period from 1920 to 1965 caused great changes in Breiðamerkurjökull glacier. It retreated very quickly, leaving a lagoon up to 190 m deep where the glacier snout had been, and several kilometres of glacial moraines were exposed on both sides of the lagoon. The lagoon grew from 8 ㎢ in 1975 to nearly 15 ㎢ in 1998. Large blocks of ice break off the edge of the glacier, which is about 30 m high, keeping the lagoon stocked with icebergs.

1903

1945

1965

1980

Selurinn (Phocaidae) / The Seals

From time to time, animals with human eyes and cute snouts can be spotted swimming in the lagoon. These are seals mammals of the suborder of pinnipeds. The small flippers are useful for swimming in the sea, but they are quite useless on dry land, where the seals have difficulty getting around. The seals chase shoal of herring and capelan into the lagoon and have a hearty meal before crawling onto the icebergs for a siesta, enjoying the sun and smiling into the lucky tourist's camera.

Skumurinn (Stercorarius skua)

A foul-tempered, brownish bird, reigning over the vast sands of Breiðamerkursandur form March until autumn. The Great Skua does not mind bridges and cars, but defends its nest fiercely, being big and bold. Most of the species living on the shores of the North Atlantic nest at Breiðamerkursandur

Jökulsárlón

Jökulsá á Breiðamerkursandi

Peeking under the glacier

Advanced technology enables us to examine subglacial landscapes. The picture above shows the bottom of Breiðamerkurjökull glacier as revealed by measurements carried out by the Science Institute of the University of Iceland. Should the glacier dsappear, deep valleys and fjords would appear. Land below sea level is shown as blue and mountains are red. The glacier margin, shoreline of lagoons and the coastline are shown as white lines.

Crossing the river

The river Jökulsá used to be a major obstacle for those who wished to cross the sand, and many lost their lives in the river. In the 18th century and even earlier, some travellers preferred to cross the glacier on foot rather than risk their lives in the river. In the 1870s, the glacier path had become commonly used and a special guide was appointed to lead travellers around the crevices on a few hours perilous journey across the glacier. In wintertime, a shortcut was sometimes practicable across an ice bridge just above the river outlet from the glacier.

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