On our planet there are large masses of ice that cover the north and south poles. This ice is not only in the sea but is also found in the mountain ranges. These ice masses are known as glaciers. When these glaciers reach such a large magnitude that they usually cover entire and extensive areas, they are called polar ice caps.
In this article we are going to tell you all the characteristics, importance, dynamics of these polar caps and what would happen if all these ice masses end up melting.
Formation of glaciers
To make way for the polar caps, it is first necessary to know how glaciers are formed so that they can spread in such a way that they eventually build a polar cap. All the ice coverage that spread during the last glaciation or ice age make up glaciers. These glaciers are of great importance as erosive agents and builders of relief, soil and landscape.
Another reason why they are important is because they constitute a great source of fresh water on the planet. There are many living beings that take advantage of the summer meltwater of the glaciers to stay alive, reproduce or make it their natural habitat.
These glaciers are formed by accumulating, year after year, the snow that falls on the bottoms and slopes of the valleys. They are located in high mountain areas. The thickness can reach a large proportion if the snow that is lost due to the summer thaw is less than that which accumulates during the snow season.
The compact mass of this snow is produced because each snowfall is compressed on the one that was previously deposited previously. If the heat of the melt succeeds in melting the ice, it will cause it to thicken and begin to move toward the bottom of the valley.
Snow density tends to increase with depth, as there is a greater amount of snow per unit area, making it more compact. This layer forms the base of the glacier and flows like a liquid. Inside the glacier, it moves more rapidly than in the lateral areas, which is why fractures, tensions, and stretching often occur, causing crevasses to appear at the top. These processes, along with the impact of the climate change, affect the dynamics of glaciers and their advance.
Glacial dynamics
The glacier is moving and uprooting the rocks that are projections that are in its path. The rock fragments that result from this movement of the glaciers are known as moraines. The area at the end of the glacier is where the thaw is formed. Here, you can see the formation of some small hills that are called terminal moraine.
As long as the glacier maintains an accumulation zone at the top of the snow from precipitation, the glacier cycle will continue. Finally, at the lowest level, the glacier melts, forming small streams of fresh water. It is important to note that the global warming is accelerating this thawing process in many regions.
There are some glaciers that flow through the valleys at the foot of a mountain system. When they come together to form a larger glacier it is known as the piedmont.
Polar caps and ice cap
Once we understand what a glacier is, how it forms, and its dynamics, we move on to describe the ice caps. If the aforementioned glacier covers plateaus and islands at high and low latitudes, it is known as a polar ice cap. These ice caps usually originate in alpine glaciers and descend through the valleys. Finally, they reach the sea on some occasions.
If a glacier is so extensive that it covers the surface of an entire continent, it is called a continental ice sheet. This is the case with the Arctic and Antarctic ice caps. This large sheet of ice flows outward until it reaches the oceans, where it breaks up into different sizes, forming icebergs. The evolution of these icebergs is also influenced by the Rising sea levels due to thawing.
The term polar caps is used to describe the different ice masses found in Antarctica and Greenland. Thus, Whenever we talk about global warming or climate change we talk about the melting of the polar ice caps. These polar caps at both poles were formed in the Pleistocene ice age, in the Quaternary period and came to cover most of the entire Northern Hemisphere.
A polar cap is known as a glacial mantle and usually have an extension of more than 1,8 million square kilometers of surface. In terms of thickness, they are at 2.700 meters maximum. These polar caps are covering most of the surface of Greenland. The bedrock only emerges near the coast where the glacier is not strong enough and it fragments forming ice tongues. When the tongues reach the sea, they break further into pieces of ice during the thaw season, forming icebergs.
Icebergs have their own dynamics and they disappear over the years. A polar cap of this dynamic covers Antarctica, only this glacier it has an area of 13 million square kilometers.
What would happen if the ice caps melted?
With climate change and the increase in the greenhouse effect, there is talk of the melting of the polar ice caps. The immediate effect of this is that the sea level would rise. Consider that the ice masses concentrate almost 70% of all the fresh water on the planet. If this water, that is on a land surface ends up melting, it will end up in the sea.
Scientists estimate that by the year 2100, sea level will have risen an average of 50 centimeters from sea level. This means that many coastal cities will be negatively affected and many other ecosystems will have to adapt again. In addition, the albedo of the earth it will also be affected since there is less white surface that reflects more incident solar radiation.
The relationship between thawing and climate change is crucial, and the consequences of melting ice caps are complex and multifaceted.
I hope that with this information you can learn more about the polar caps and the consequences of their melting.