Glaciers and Climate Change

The last section of glaciers that I am going to look at is that of climate change. I think it is important to look at this as it is a topic that is nearly always on the news and is something that everybody hears a lot about today. Although it is a dynamic topic, I think it is good to look at it in context with glaciers as when people talk about climate change it is often how the world’s glaciers will respond and in turn, how it will impact on sea levels.

Climate Change

Firstly, it is important to define what exactly climate change is. To begin with, it is essential to note that when people talk about climate change they are talking about anthropogenic climate change – that caused by humans. This occurs as a result of the release of greenhouse gases in the atmosphere which trap heat which enters Earth (the enhanced greenhouse gas effect). Climate change refers to any process that may cause an adjustment to the climatic system. This phrase is often better to use than ‘global warming’ as climate change can have many other effects than solely warming.

Glaciers and climate change

Shrinking glaciers

The video above begins to illustrate what is happening when people talk about climate change having an effect on glaciers. They are very sensitive to temperature fluctuations and so it is very easy to see the effect that an increase in temperature can have on a global scale since the beginning of the twentieth century, glaciers around the world have begun to rapidly recede, with few exceptions. This occurs as a result of an increase in temperature which then leads to an increase in glacial melt and also causes calving. Both of these two processes lead to a glacier receding.

The Columbia glacier, Alaska

One of the most renowned glaciers that has been affected by climate change is the Columbia glacier in Alaska. One of the fastest moving glaciers in the world, over the past 25 years it is estimated that it has receded by 15km. The video linked above is very good for illustrating the extent of how much the glacier has receded over this time period – very beneficial for putting the facts into a more comprehensible visual aid.

Chacaltaya Glacier 

Located in Bolivia, the Chacaltaya glacier was hugely relied upon by people living near the glacier in two main cities; both for water and for tourism. This glacier was once the world’s highest ski run and people from around the world would visit the glacier every year. However, in 2009 the glacier disappeared completely bringing economic fears and those of water issues. Nearly 80 million people rely on Andean glaciers as a source of water and electricity (Hydro-electric Power) and with temperatures rising as they currently are, there are many people at risk.

The image shows how far the glacier had receded from 1940 to 2007. However, in 2009 the glacier had completely disappeared.

Karakoram Glaciers

Glaciers located in the Himalaya Mountains; in particular those flowing in the Karakoram mountain range on the border of China and Pakistan, have actually been growing over the past decade, despite the global pattern of glaciers receding and is due to an increase in snowfall to the region.

Looking at a range of different websites and text books, it is clear that the global general pattern of movement is that of glaciers receding. Although there are some exceptions (mainly those in the Karakoram region) the increasing average temperature of the Earth is resulting in the melting of glacial ice which is contributing to a rise in sea levels. This section could be taught as a round up of the glacier topic with students using the knowledge that they have gained from learning about glaciers and putting it all together to look at the effect of climate change on them (for example, using key words such as calving and ablation) as well as using their locational knowledge to find the glaciers that are receding and those that are growing.

Links used:

http://www.bbc.co.uk/science/earth/water_and_ice/glacier#p00gbg92 – Glacier video

http://nsidc.org/cryosphere/glaciers/questions/climate.html - National Snow and Ice Data Centre

http://www.extremeicesurvey.org/index.php/education_toc/glaciers_and_global_warming - Extreme Ice Survey

http://education.nationalgeographic.com/education/encyclopedia/glacier/?ar_a=1#page=3 – National Geographic

http://www.bbc.co.uk/climate/impact/glaciers.shtml - BBC

http://www.guardian.co.uk/environment/2010/dec/21/what-is-climate-change The Guardian

http://news.bbc.co.uk/1/hi/8046540.stm#image – BBC, Bolivian glacier

http://www.guardian.co.uk/environment/2012/apr/15/karakoram-glaciers-grown-research - The Guardian, Karakoram glaciers