“Examine how glaciers operate as system”(25)
Glaciers are moving bodies of ice which can form at high latitude and/or altitudes across the world. Glaciers can be described as systems as they have inputs, output, stores and flows within them; this is what makes up a system. Topics to be discussed are glacial inputs, outputs, it’s mass balance at a cold and warm base glacier as well as how a system may be altered due to the climate change in the atmosphere of the glacier. Glaciers can vary in movement distance however within a surge, a glacier can move up to 300m per day.
Within a glacial system, there are inputs, outputs, stores and flows. The inputs within a glacier could be: any form of precipitation, gravity, insolation, melt water from other glaciers as well is rock debris. An example of a store within a glacier may be air pockets within the structure of the glacier and a flow/transfer of a glacier would be: streams or lakes and melt water transferring. Lastly, an output of a glacier may be: lakes, melt water in liquid form and sediment.
The mass balance of a glacier is the relationship between the inputs and outputs within the seasons of a year. Within the winter, there’s a high accumulation curve, where inputs are high through precipitation as well as a low ablation curve which is the outputs of melting; this causes the glacier to be at its most gaining period. However, in summer this is where the ablation is at its highest as well as the accumulation is at it least and so, this is where the glacier is at its highest melting period. This can be shown within a mass balance diagram:

There are two types of glaciers, warm and cold based glaciers. Warm based glaciers are found at low latitude, high altitude locations such as the Alps. Here, movement comes in the form of pressure melting; where the temperature of the surrounding area is the melting point temperature or just below, causing basal sliding which allows a rapid movement of the glacier of 20-300m per year. Secondly, cold base glaciers are found in high latitude, low altitude areas such as those in the Arctic. Here, there is very little erosion taking place due to the slow movement that it takes due to the cold temperatures not allowing basal sliding or pressure melting to take place.
The first cause of movement is Basal sliding which occurs at a warm based glacier, where the temperature is at or just below the pressure melting point and so, this allows melt-water to form between the ice and valley floor which reduces the friction. Basal sliding has many components of mechanisms to it. Firstly, slippage occurs when ice slides over the valley floor due to the lessened friction from the melt water between the ice and the bedrock. Secondly, ‘creep’ is where the glacier experiences deforming within its structure due to obstacles such as rocks and boulders within the path of the glacier; in this case, glaciers experience ‘plastic flow’ which allows them to spread out and around the obstacles in order to carry on moving. Next, regelation slip occurs where added pressure on the up-glacier side of a bedrock obstacle which causes further melting. This melt water then adds to the sliding of the glacier, which allows easier movement over the obstacle; after the glacier has moved over the obstacle, the ice refreezes where the pressure is lessened. Finally, bed deformation is where the glacier is carried by saturated sediments on a gentle gradient where the water is under high pressure. The high pressure within the sediment reduces frictions between individual grains of the glacier which causes the sediment to deform and thus, flow.
Secondly, due to cold based glaciers staying at an extremely cold temperature, they do not move through the process of basal sliding, but internal deformation which is made up of two components. The first is intergranular flow. This is where the individual crystals move in relation to each other, which allows a very steady movement of the glacier. Next, laminar flow is the movement of layers within the glacier which is often layers of annual accumulation. This is at a steady pace and so, the movement of cold base glaciers is much slower than that of a warm base glacier; due to the ice characteristics, this depends on the amount of movement which is experienced within a year.
Climate change can also have a great impact on the system of a glacier. The first long term impact on the glacier system is the changes in the Milankovitch cycle causing glacial and interglacial periods. During relatively cold glacial periods, there has been a positive balance within the glaciers, leading to their growth. However, during periods of warmer interglacial periods, there has been a negative balance of the glaciers leading to their reduction. As well as natural climate change, there have also been changes in the climate which are due to anthropogenic reasons. Humans have invested heavily in industrialisation which has led to an increased output of co2 emissions which have increased the greenhouse effect; which raises the global temperature and thus, has an adverse effect on the world’s glaciers. In Greenland and Antarctica, there has been a recorded continuous decrease of ice on both ice sheets at a huge pace. In 2009, Greenland lost 230 gigatons and Antarctica, 140 gigatons. Adding to this, the Gangotri glacier in the Himalayas has been rapidly receding since 1980s and within the last 25 years, has receded more than 850 metres.
To conclude, glaciers are dependent on the climate around them to determine their inputs, outputs, stores and flows and a change in their surroundings such as climate change, can have both positive and negative effects on their growth. Within the future, glaciers could be recorded to experience further negative balance by the anthropogenic causes of climate change.

There are two types of glaciers; warm and cold based glaciers. Warm based glaciers are found in low latitude and high altitude locations such as the Alps, where their inputs and outputs are increased by the climate, whereas cold based glaciers such as those in the Arctic, which are found at high latitude and low altitude, are limited by their climate.