What is the cryosphere?
The cryosphere is the Earth’s frozen water system and frozen water can be found all over the world, for example, during the winter, snow blankets the ground at mid and high latitudes, and in icy waters of the polar oceans, sea ice and icebergs float.
Lands in the Earth’s polar regions are surrounded by ice shelves and in these regions, glaciers and larger ice sheets move slowly over land. The glaciers are found on high mountain peaks all over the world while polar soils, known as permafrost, are soils filled with ice water either sea ice water or arctic ice. The cryosphere of the Earth is made up of these various types of frozen water and it contains roughly three-quarters of the world’s freshwater.
Snow, ice on ponds and lakes in mid-latitude locations which are some components of the cryosphere, is only present during the winter months whereas the glaciers and ice sheets the remaining components of the cryosphere, remain frozen all year and can do so for tens of thousands, if not hundreds of thousands, of years. Some of the ice areas in the Antarctic ice sheet, which covers the majority of the continent, have been there for nearly a million years.
Definition of the cryosphere
The term “cryosphere” is derived from the Greek word “kryos,” which means “cold,” and shaira which means “sphere.”
Our planet’s cold regions have an impact on the climate of the entire planet, this means that the cryosphere is essential to the daily lives of the people, plants, and animals who call it home. When scientists refer to the cryosphere, they are referring to areas where water is solid, where low temperatures freeze water and turn it into ice and this is the simple meaning of the cryosphere.
The cryosphere is commonly thought to be at the top and bottom of our planet, in the polar regions. The area surrounding the North Pole which is the top of our planet is known as the Arctic, and the area surrounding the South Pole known as the bottom of our planet is known as the Antarctic. These regions can be found on the Arctic maps. However, snow and ice can also be found in many other places on Earth and not only at the top and bottom of the Earth as commonly thought.
Where is the cryosphere located?
Location of the cryosphere
- The Arctic
- Other places in between the Arctic and Antarctic
The above-listed regions are the places where the cryosphere is can be found.
The Arctic Ocean, which is cold, surrounds the North Pole and contains sea ice (the arctic ice) that grows in the winter and shrinks in the summer. The Arctic Ocean is surrounded by frozen ground and permafrost while the glaciers, snow, and ice cover the surrounding land, which includes Greenland (The land is in a thick sheet of snow and ice area).
Antarctica is a continent filled with ice commonly termed the icy continent and it is located at the South Pole of the earth. Antarctica’s landmass is covered by a massive ice sheet, and in some places, floating ice shelves extending into the ocean. Icebergs form when the outer sections of ice break off or “calve” from these shelves. The icebergs float in the oceans, melting and dissolving as they drift into warmer waters.
Other places in between the Arctic and Antarctic
The cryosphere can also be found at high elevations far from the cold poles. The snow on Mount Kilimanjaro, for example, is in Africa, and the top contains some components of the cryosphere. Another example is the frozen soil found high in the mountains of the United States, as well as in Canada’s, China’s, and Russia’s northern reaches. During the cold winter months, the cryosphere expands when snow falls and soil, rivers, and lakes freeze.
Components of the cryosphere
- • Snow
• Sea ice
• Ice sheets
• Ice shelves and icebergs
• Solid precipitation
Snow forms when moisture in clouds freezes into ice crystals that stick together at temperatures below 0º C (32º F). When these frozen clouds accumulate to a sufficient weight, snow falls as precipitation. Snow comes in a variety of forms, including snowflakes, graupel, and sleet.
Snow can be classified based on its type and formation after it has fallen. Some common examples include firn, slush, cornice, and sastrugi.
Firn, also known as névé, is high-density snow that has been present for more than a year and slush is snow that has melted and become mixed with water; whereas a cornice is an overhanging accumulation of snow and ice caused by wind (usually found on a ridge or cliff face).
Sastrugi on the other hand are sharp, irregularly formed ridges on a snow surface that grow many meters long and up to a meter high, parallel to the wind direction. Where there are strong winds, sastrugi and cornices are common.
Terrestrial snow has the greatest geographic range of the cryosphere components. In the winter, it covers nearly 50 million km2 of the Northern Hemisphere, affecting both heavily populated mid-latitude regions and higher latitudes. Snow’s high albedo reduces solar energy absorption and encourages lower surface temperatures and it also protects the land surface from large energy losses during the winter and lessens the severity of soil frost and smoothes the land surface, lowering wind resistance, and altering energy exchanges with the atmosphere. These interactions have a significant impact on the land surface energy budget, as well as local and regional effects on atmospheric circulation.
Sea ice forms at the sea surface when seawater freezes, which happens at a lower temperature than pure water due to salinity. Sea ice, unlike icebergs, glaciers, ice sheets, and ice shelves, forms and melts entirely in the ocean because it is relatively thin, ranging in thickness from a few centimeters to a few meters. Sea ice is classified according to its age, thickness, and shape. For example, frazil ice, drift ice, pancake ice, floes, and pack ice are all different classes of sea ice.
Sea ice acts as a “thermal blanket,” limiting heat and moisture exchanges between the ocean and the atmosphere as the large difference in reflectivity between ice (bright) and ocean (dark), results in more heat being absorbed by the ocean rather than reflected back into the atmosphere.
The seasonal sea-ice zone is highly productive biologically, as it is an important component of the carbon cycle. For instance, fast ice provides important wildlife habitat, and the shear zone between fast and drifting ice frequently results in open water in these areas, which benefits the biota.
Glaciers are ice masses that form on land and the ice is formed as a result of multiple seasons of snowfall and they move very slowly downhill.
Facts about the glaciers
- • Glaciers cover 10% of the world’s land
• Because of climate change, they are now smaller than they were previously.
• They change the land through which they flow, sculpting landscapes with their weight
• Because of the algae that live in the top layers of the ocean, it can appear pink at times in the ice and snow
• Glaciers store 69 percent of the world’s fresh water and provide water to millions of people worldwide
Permafrost or frozen ground is soil or rock that has had some or all of its water frozen and when the ground remains frozen all year, or it is termed a permanently frozen soil.
Facts about permafrost
- • It is mostly found in the Arctic and Antarctic, but it can also be found at high elevations on the Earth.
• As the climate warms, permafrost melts.
• Because the soil is thawed for at least part of the year, it frequently has an “active layer” near the surface where plants can live.
• Permafrost causes issues for people who are constructing structures, roads, or dams because it can shift when it melts.
• It stores greenhouse gases such as carbon dioxide and methane; scientists are investigating how these gases will affect the climate as temperatures rise and permafrost thaws.
An ice sheet is a body of ice on a continental scale that flows towards the ocean under its own weight and for the past thousands of years, ice sheets forms as snow accumulates from year to year, gaining mass and compressing older layers into ice. The last ice age’s two major ice sheets cover the majority of Greenland and Antarctica.
Ice sheets are of great importance to the Earth’s past climates because ice cores collected from ice sheets provide detailed information about past climate and environmental conditions on timescales ranging from (seasons – decades – hundreds of millennia), depending on accumulation rate.
Ice shelves and icebergs
Ice shelves are ice platforms formed when ice sheets and glaciers move out into the oceans. The majority of ice shelves are found in Antarctica and Greenland, as well as in the Arctic near Canada and Alaska. Whereas icebergs are ice chunks that break off from glaciers and ice shelves and float in the oceans.
Facts about ice shelves and icebergs
- • Only when ice shelves leave the land and push into the water do they raise sea level and not when they melt in the water.
• As temperatures rise, they break off and melt; in 2002, Antarctica’s massive Larsen B Ice Shelf shattered in a matter of months, sending hundreds of icebergs into the ocean.
• They provide a home for krill, which are small fish eaten by penguins, seals, whales, and sea birds.
• They are an important area of study for many scientists who study biology, glaciers, climate, and other subjects.
• They could reveal information about the future of ice sheets and glaciers in a warming world.
Ice forms when temperatures fall below the freezing point and liquid water solidifies, resulting in a tightly bonded substance. Ice is a component of the glaciers, sea ice, ice shelves, icebergs, and frozen ground.
Facts about ice
- • It exists all over the world, but it is most common in high latitudes, high elevations, or at night when temperatures are low.
• If the climate continues to change and temperatures rise, life in the oceans, lakes, and rivers may become less common.
• It provides water for people, animals, and plants.
• Ice on lakes and oceans can become so thick that special ships known as icebreakers must cut a path through it.
Solid precipitation forms in clouds where air temperatures are below zero degrees Celsius (32 degrees Fahrenheit). Snow (collection of ice crystals), snow grains, snow pellets (white, opaque ice particles that fall from the sky), diamond dust (small ice crystals that float with the wind and fall slowly), snowflakes (very small opaque white ice particles that fall from a cloud and are relatively flat or elongated) hail, and ice pellets are all types of solid precipitation.
Examples of the cryosphere
- • Snow
• Sea ice
• Arctic ice
• The glaciers
• Ice sheets
• Ice shelves
• Ice pellets
The above listed are some of the examples of cryosphere that are found on the Earth.
Facts about the cryosphere
- It exists all over the world, but it is most common in high latitudes, high elevations, or at night when temperatures are low.
- If the climate continues to change and temperatures rise, life in the oceans, lakes, and rivers may become less common.
- It provides water for people, animals, and plants.
- Ice on lakes and oceans can become so thick that special ships known as icebreakers must cut a path through it.
- Only when ice shelves leave the land and push into the water do they raise sea level and not when they melt in the water.
- As temperatures rise, they break off and melt; in 2002, Antarctica’s massive Larsen B Ice Shelf shattered in a matter of months, sending hundreds of icebergs into the ocean.
- They provide a home for krill, which are small fish eaten by penguins, seals, whales, and sea birds.
- They are an important area of study for many scientists who study biology, glaciers, climate, and other subjects.
- They could reveal information about the future of ice sheets and glaciers in a warming world.
- It is mostly found in the Arctic and Antarctic, but it can also be found at high elevations on the Earth.
- As the climate warms, permafrost melts.
- Because the soil is thawed for at least part of the year, it frequently has an “active layer” near the surface where plants can live.
- Permafrost causes issues for people who are constructing structures, roads, or dams because it can shift when it melts.
- It stores greenhouse gases such as carbon dioxide and methane; scientists are investigating how these gases will affect the climate as temperatures rise and permafrost thaws.
- Glaciers cover 10% of the world’s land
- Because of climate change, they are now smaller than they were previously.
- They change the land through which they flow, sculpting landscapes with their weight.
- Because of the algae that live in the top layers of the ocean, it can appear pink at times in the ice and snow
- Glaciers store 69 percent of the world’s fresh water and provide water to millions of people worldwide
- Cryosphere today can be obtained from the latest sites that give daily updates of the components around the globe.
- The Arctic maps can be used to know more about the cryosphere in that region.
- Cryosphere journals are also a helpful tool to learn about it.
- Arctic sea ice keeps the polar regions cool and contributes to global climate regulation.
- Because satellites measure extent more accurately than other aspects of sea ice, such as thickness, the Arctic sea ice extent is more closely monitored than other aspects of sea ice.
- Ice area is the part that is covered by sea ice and it is measured in kilometers
- Each year, the Arctic sea ice minimum marks the day when the sea ice extent is at its lowest.
How does the cryosphere interact with the geosphere?
When glaciers and sheets of ice from the cryosphere erode the rocks on the geosphere, there you can see that geosphere interacts with the cryosphere.