Glaciers in Iceland cover about 11% of the country. Vatnajökull, the largest glacier in Europe covers 8% of our territory. The largest glaciers are in the south and in the central part of the country, it is because there is more rainfall there than in the north.
The looks of the glaciers change fast and a big part of the glaciers in Iceland are icefall glaciers, meaning that they slowly creep down towards sea level. All Icelandic glaciers are temperate glaciers, where the temperature at the bottom of the glacier is at freezing point, sometimes above sometimes below. This makes the glaciers move but it depends on the slope of the landscape and how fast they are going, the average speed is about 50-200 meters per year.
Glaciers in Iceland were small around the time of the settlement, grew really much while the period, which was called the “little Ice Age”, took place. The little Ice Age was a period of cooling, but it was not a true Ice Age. It took place from about 1350 to about 1850. They glaciers grew up to the 1900 and then started to retreat, around 1988 they were in place for several years but were then retreating again. Now the average temperature is 5° and it does not have to drop much more so the glaciers would start growing again.
A volcano erupts under the glaciers about ten times a century. When that happens there are massive quantities of glacier ice that melt. In Iceland there are some glaciers that lie over geothermal areas, so the glacier ice melts from below. From that depressions form in the glacier and in many cases it causes glacier burst.
Iceland has been getting warmer since the early 20th century, roughly 0.7°C per century. There have been big changes in Icelandic climate; it has been getting warmer, even more than in the rest of the world during the same period. The first years of this century have been as warm as it is during the best interglacial periods in the middle of the last century. This picture shows how an Icelandic glacier expert thinks the retreat of Hof glacier will be. The first picture is from 1990 and the last one is how he thinks it will look like in 2190.
Signs of warming are evident in Icelandic nature; all of the glaciers are retreating fast. Because the glaciers are thinning the southeast coast of Iceland rises fast. For example, Vatnajökull is thinning by an average of 1 m/year. Sea level rise could therefore become a significant problem, especially where land is lower. This also applies to lowlands in the capital and on the Reykjanes peninsula.
When n icefall glacier is balanced, that is that it is not moving forward nor is melting, the melting is balanced with the advancing, that is the glacier moving forwards towards the ground, of the glacier, when it retreats the melting is faster than the advance but the opposite is when it advances. This process is highly related to the temperature.
Around 1934-1935 the lagoon started to form at the edge of Breiðamörk glacier when it began to recede. Before it happened, the glacial river Jökulsá ran from the glacier about 1,5 kilometer to the sea. Since 1950 the glacier has retreated and the lagoon is getting bigger and bigger.
The year 1975 the lagoon measured about 7.9-km2 but today it is 25 km2. Breiðamörk glacier lies actually in a long and deep fjord and the lagoon is 248 feet in depth.
Students from FAS go every year to measure one glacier in the county, Heinaberg glacier. The glacier lies in a lagoon and hence is more changes to it than the glacier that lied on land.
Written by Dóra, Nejra and Siggerður