The Importance of Glaciers for the Planet and Climate

Our planet’s glaciers are found mainly in Antarctica, Greenland, the Arctic, and Patagonia. They are major sources of freshwater. So, why do they exist, and what role do they play in our environment?

Chugach State Park, Alaska, United States

Glaciers are immense formations of ice, primarily comprised of a significant volume of compacted snow. Their development spans an extensive duration, stretching up to 30,000 years for the largest ones.

The genesis of a glacier transpires within the frigid polar zones of the planet, where temperatures plummet to their nadir. Within these regions, the process of water’s cooling and crystallization unfolds. Water molecules draw intimately together and solidify, initiating the formation of ice crystals that accrue stratum upon stratum across the Earth’s surface, amassing considerable depths. The ice resulting from this natural activity has an extremely low melting point, even reaching hundreds of degrees below zero.

Types of Glaciers

u-shaped valley, valley glacier hanging glacier.
Hanging glacier. Image: CMU.

In order to better study glaciers, differences appear according to their size and shape. There are two main types of glaciers and their subtypes, the glacier types:

  1. U-shaped valleys or Valley Glacier, referred to as a glacial structure with a tongue-like form, courses its way through a valley landscape. It can exhibit either a relatively slender shape or a broader expanse, extending over substantial areas. Among the most prevalent, these valley glaciers serve as crucial subjects for investigating shifts in climate patterns.
  2. Ice sheet or Continental Glacier, commonly labeled as an ice cap, stands as a monumental and extensive mass of ice enshrouding an expansive tract of land. These ice caps are predominantly situated in Antarctica and Greenland.
  3. Alpine Glacier, emerging within mountainous terrains at elevated altitudes, gracefully descends along the steep inclines of these peaks, adopting diverse manifestations like cirque glaciers, corrie glaciers, and hanging glaciers.
  4. Piedmont Glacier, a distinctive glacier classification, materializes at the foothills of mountains or mountain ranges, gracefully fanning out into lowland plains. The characteristic fan-shaped appearance commonly defines these piedmont glaciers.
  5. Tidewater Glacier, arising from the progression of ice towards the ocean, gives rise to floating ice shelves as it meets the waters. With a pivotal role in regulating sea levels, tidewater glaciers hold significant importance.
  6. Icefield Glacier, enshrouding expansive plateaus, presents a predominantly level or slightly inclined profile. These glaciers exhibit gradual movement over extensive distances, covering vast swaths of terrain.
  7. Rock Glacier, characterized by a covering of rock fragments and moraines, usually takes form in mountainous locales where rocky materials accumulate atop icy surfaces.
  8. Hanging Glacier, a petite glacial entity, clings tenaciously to the mountainside, often positioned above larger glaciers or valleys. Adorned with picturesque charm, these hanging glaciers form captivating natural sights.

Why Do Glaciers Matter?

Edge of the Antarctic ice sheet on Mather Island, Prydz Bay, Antarctica.
Edge of the Antarctic ice sheet on Mather Island, Prydz Bay, Antarctica. Image: Hannes Grobe, Alfred Wegener Institute.

Glaciers possess a critical role in maintaining life on our planet due to their possession of approximately 70% of the Earth’s fresh water in solid form. The process of glacier melting, beyond simply depleting our freshwater reservoir, sets off a cascade of socio-environmental predicaments. These include the escalation of sea levels, occurrences of floods, alterations in oceanic water temperatures, a decline in biodiversity, and various other issues. As a result, it becomes imperative to mitigate the glacier melting phenomenon that has been observable for numerous decades.

Furthermore, glaciers exert a substantial influence on the Earth’s albedo, which signifies the proportion of solar energy that gets reflected from the planet’s atmosphere and surface. This reflection of solar flux from Earth’s surface has a noteworthy influence on the global climate. The high albedo possessed by ice causes it to reflect incoming light radiation, thereby contributing to this intricate process. As glaciers melt, the terrestrial albedo experiences a reduction in its overall magnitude. Consequently, the energy that was previously emitted into space undergoes conversion into heat, thereby contributing to the escalation in temperature.

Lastly, it is noteworthy that glaciers encapsulate traces of air and water that originated thousands of years ago. The scientific examination of these elements by researchers significantly enhances our comprehension of our planet and the alterations in climate that it has undergone.