[New post] Disappearing Glaciers and Climate Change
devongeography posted: " For a number of years (pre-COVID), I worked for Rayburn Tours as a guide in Iceland. One of the regular locations for visits for my school groups has been the Solheimajokull glacier, an easily accessible ice feature in the south of the country. Since"
For a number of years (pre-COVID), I worked for Rayburn Tours as a guide in Iceland. One of the regular locations for visits for my school groups has been the Solheimajokull glacier, an easily accessible ice feature in the south of the country.
Solheimajokull. Image: Paul Berry
Since first visiting Iceland way back in the early 1980s, I have seen a number of changes to this glacier – literally watching it slowly melt and disappear before my eyes. When I first visited the glacier, it extended right to the current car park area, but now there is a lengthy stroll needed to reach the snout of the ice.
Dirt Cones on Solheimajokull. Image: Paul Berry
Ice Moulin. Image: Paul Berry
Hiking on Solheimajokull. Image: Paul Berry
Solheimajokull Crevasse. Image: Paul Berry
Solheimajokull Snout. Image: Paul Berry
The reduction of this glacier is part of a natural process of ice loss as we continue to move away from the times of the last Ice Age. However, in more recent years, I have used my visits to Solheimajokull to discuss with students the effects of anthropogenic climate change, which is hastening the melting process.
Solheimajokull and Lagoon. Image; Paul Berry
Some facts about Solheimajokull
Solheimajokull = 'Glacier of the Sun'
Outlet glacier extending from Myrdalsjokull
5 miles long, around 1200 metres wide
1995 onwards - rapid retreat of 50 metres per year
1995 to 2010 - 700 metres retreat
Current lifespan estimated to be between 150 - 200 years
Kayaking on the lagoon, Solheimajokull. Image: Paul Berry
Lagoon Iceberg, Solheimajokull. Image: Paul Berry
A photography project involving the University of Iceland and the Icelandic Met Office has compared images taken in the 1980s with present-day drone photographs. The results have highlighted the staggering extent of the ice loss from Iceland's southern glaciers in such a short time.
Iceland's Met Office says the country's glaciers have retreated by a total area of about 750sq km since 2000 - and are losing an average area of 40 sq km each year.
This image of the Heinabergsjökull glacier was taken in 1989. Image: Iceland Land Survey
The 2019 drone image shows the extent that the glacier has lowered over 30 years. Image; Kieran Baxter, University of Dundee
The images below are of Breiðamerkurjökull glacier. The top photo was taken in 1989 and the one below was taken this year, showing how much ice has been lost over this period.
: Land Survey of Iceland / Kieran Baxter
Iceland has already lost its OK glacier. Last summer, people gathered to commemorate the loss of the glacier, which became too thin to move.
Image: Sky News
Image; The Guardian
Watch a short film about the disappearing OK glacier here:
However, the disappearing glaciers of Iceland are only a part of a wider story. The problem of glacier loss caused by climate change is a global issue. Recent news articles have highlighted the rapid retreat of glaciers across the world, leading the world into a humanitarian crisis. It has been calculated that 70% of the earth's freshwater is stored in glaciers – but rising global temperatures are causing these giant rivers of ice to quickly melt away.
The latest Intergovernmental Panel on Climate Change (IPCC) report warned that smaller glaciers in Europe, Africa, the Andes and Indonesia were projected to lose more than 80% of their current ice mass by 2100 if carbon emissions remained high. The resulting rise in sea level could have huge consequences for millions of people, the UN panel warned.
As an example, Italy's Forni Glacier has retreated by almost 2 kilometres in the past 150 years:
Forni Glacier, Italy. Image; Getty Images
The loss of glaciers in Iceland can be linked to issues with water supplies, electricity production, and loss of tourism revenue, but in some developing regions of the world the consequences may be life-threatening.
Scientists calculate that even if global warming is limited to 1.5 degrees in the near future, a third of the ice in the Himalayas will be lost. This could seriously threaten water supplies for the 250 million people (a population four times the size of the UK) living in this region that rely on rivers fed by glacial melt. A study published in 2019 found that the rate of glacier retreat in the Himalayas has doubled since the late twentieth century. Other parts of the world are similarly affected. A threat to water supplies resulting from ice loss also exists in the Andes in South America.
A study published in 2020 found that Greenland's largest glaciers are currently melting at levels close to what scientists had previously expected under a future worst-case scenario. Radical changes will be needed to stem this dramatic glacier loss.
Alesk River, Alaska. Image; NASA
An article in the Guardian newspaper at the beginning of May introduced me to a new geographical term connected to glacier loss. It talked of 'river piracy', where communities are facing the sudden disappearance of their rivers due to climate change. This piracy, or 'stream capture' occurs when one river is diverted into another because of glacier melt.
The photograph above shows the mouth of the Alsek River in Glacier Bay National Park in Alaska. It is forecasted to shift 20 miles south from its current location.
Scientists predict as we move towards a world with fewer glaciers, land that has been continuously covered by ice for many centuries will become ice-free, thus redirecting rivers in high mountain areas. In most instances, this redirection will be inconsequential, but in some areas where communities rely on the river's flow, the changes might have a more significant impact.
As an example, the Yukon provides us with a useful case study. For hundreds of years, the Slims (Ä'äy Chù) River carried meltwater northwards from the vast Kaskawulsh glacier into the Kluane river then into the Yukon River towards the Bering Sea. But in spring 2016, a period of intense melting of the glacier permanently redirected the meltwater of the Slims River towards a steeper gradient east via the Kaskawulsh River, into the Gulf of Alaska thousands of miles from its original destination.
Incidentally, glacial river piracy is also taking place in Iceland. In 2009, a glacier feeding theSkeiðará River retreated, leaving the longest bridge in Iceland – 900 metres long – over dry land.
Another new term came to light this month – 'glacier blood' as a sign of climate change.
French scientists have expressed concerns about Alpine snow turning to a pinkish red colour, a phenomenon that has been called 'sang de glacier' ('glacier blood') or 'watermelon snow'. This has been caused by a bloom of normally invisible algae that has changed colour to protect themselves from ultra-violet light – a possible sign of global warming. Unfortunately, the red colouration increases glacier melt by getting rid of the 'albedo' effect – reflecting the sun's rays less, and causing it to heat up more quickly.
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