Introduction
Glaciers and icebergs are vast masses of snow that consolidate into dense ice over the centuries. Therefore, it is understandable why people use these terms interchangeably (snow is snow; does it matter what one calls a consolidated mass of snow? The short answer is yes, it does.). However, they differ in several ways – how they form, their location, size, and shape. Glaciers and icebergs are crucial because they are the reason oceans and rivers do not dry up. They are a critical source of freshwater, making them indispensable to people.
Glaciers hold 69% of the world’s freshwater. The meltwater from glaciers and icebergs is the predominant source of freshwater for animals, plants, and humans. The melting of icebergs (at the normal rate) is not a big concern, as they are small chunks of ice that melt and feed the rivers; however, it is a matter of great concern if the glaciers start to melt. Imagining a world without glaciers is horrifying (I hope it never comes to that and people do their best to preserve these freshwater reservoirs).
Glacier vs. Iceberg
Glaciers are bodies of dense ice that form only in land where the accumulation of snow exceeds its vaporization, erosion, etc. Icebergs are the freshwater ice that breaks off from glaciers.
Difference Between Glacier And Iceberg In Tabular Form
| Parameters of Comparison | Glacier | Iceberg |
| Size | Glaciers are humongous compared to icebergs. | Icebergs are small in comparison to glaciers, as they are merely chunks of ice that break off from glaciers. |
| Location | Glaciers are predominant in polar regions (continental glaciers) but are also found in mountains (alpine glaciers). | Icebergs float on fresh or saltwater bodies. |
| Surface Area exposed above water level | The entire glacier is visible as they form on land above water level. | Only the tip of an iceberg (around 10% of surface area) is visible above water level. |
| Formation | Continuous accumulation of snow transforms into ice over one or more centuries. (No wonder geologists are screaming at the top of their lungs about the dangerous effects of global warming!) | They break off from continental or alpine glaciers. However, icebergs created from alpine glaciers are fewer than the ones created from continental glaciers. |
| Composition | Glaciers are made up of pure snow and ice. | Icebergs are made up of pure ice. |
What Is A Glacier?
Glaciers have mesmerizing pockets of color caused by their ice's temporary thawing and refreezing. The breathtaking colors are worth braving the bone-chilling cold to see. These streaks of color may be seen in icebergs that calved (broke off) from that part of the glaciers. However, watching a colorful iceberg is not as stunning as the view vibrant glaciers provide. People with a penchant for large glaciers will have a fun time visiting Antarctica, whereas those fascinated by the glaciers’ varying shapes and sizes will be better off touring the Arctic (don’t worry, not everyone gets stranded like Overgård in Mads Mikkelsen’s film Arctic.).
Glaciers form in regions with heavy and continuous snowfall. The weight of the falling snow compacts the already accumulated snow, resulting in the formation of glacial ice. In temperate glaciers, the melted snow refreezes and changes into granular ice, better known as firn (a state between snow and ice). A firn transforms into glacial ice under compaction. Glacial ice is denser than ice formed from freshwater, as it contains fewer air pockets. It is easily recognizable by its unique bluish tint.
Monitoring glaciers is one of the best ways to track climate change (NASA and several others fascinated with these ice bodies keep an eye on them to study them carefully.). Increasing global warming causes glaciers to melt at a faster rate, resulting in increased global sea levels. Coastal cities will flood if a huge part of the glaciers melt.
Types Of Glaciers
The following are the various types of glaciers:
Continental Ice Sheets
Continental ice sheets are the largest glaciers and are present in Antarctica and Greenland (ever wondered why it is called Greenland when it is full of ice?). Any glacial body that extends to more than 19,000 sq. mi. qualifies as an ice sheet. The Antarctic Ice sheets extend to 5.4 million sq. miles (it is facts like these that make people truly feel like the specks of dust that they are in the universe.).
Alpine Glaciers
Alpine glaciers form on mountain crests and are classified as follows:
Valley Glaciers
Valley glaciers can carve through bedrock and change a region’s topography. Usually, U-shaped valleys such as the Yosemite Valley result when the glacier carves. The process takes several million years; therefore, the chances of present-day people witnessing such a phenomenon are negligible. A mass of interconnected valley glaciers is called an ice field.
Tidewater Glaciers
Tidewater glaciers extend out to the ocean (they are essentially mountain or valley glaciers terminating at the sea.). Icebergs calve from their fracture zones and are released into the sea. Seventy percent of the global ice loss into the ocean is because of them. The John Hopkins Glacier is an example of a Tidewater Glacier. People who love seals would love watching this glacier as many seals use it as their pupping habitat.
Rock Glaciers
All glaciers are covered with some amount of rock and debris; however, rock glaciers have more rocks than the standard amount. In fact, some rock glaciers have more rock than ice. Therefore, they do not resemble glaciers much (but hey, don’t judge a book by its cover.). The Atlin Glacier in British Columbia, Canada, is an example of Rock Glaciers.
Some Interesting Facts About Glaciers
Glaciers are fascinating in their own way. Aside from their beauty, several other facts make them interesting and worth getting to know about, and they are as follows:
- The Atlantic ice sheets are glaciers that have been around for 40 million years (no wonder glaciers are referred to as permanent bodies of ice!).
- Glacier growing is a common practice in the Himalayan Regions to increase the water supply for the crops. The ice from the natural glaciers is acquired and placed in man-made caves at high altitudes.
- Glaciers are present even in regions near the equator. In fact, 47 countries have glaciers, proving that glaciers do not form only in Polar Regions (Alaska has around 100,000 glaciers, most of which are unnamed.).
- Some glaciers form over active volcanoes under frigid temperatures (nature never ceases to surprise.).
- Tidewater glaciers shoot ice when they crack at the oceanfront every day (who wants to take a shot at recording the phenomenon?).
What Is An Iceberg?
A fracture in the ice sheets leads to the calving/separation of chunks of ice from it; these chunks are called icebergs. Icebergs detach from the glaciers and float away into water bodies. So, how do icebergs float (no, the answer is not magic.)? The density of frozen freshwater (icebergs are, in essence, exactly that) is less than the density of liquid saltwater. That is why an iceberg floats; however, since the difference in density is only around 10%, only a small part of the iceberg is visible above water level.
Ninety percent of an iceberg’s surface area is submerged in water, meaning the ships will never know what hit them if they are not on the lookout for icebergs. The Titanic sank because of an iceberg! Moreover, icebergs melt from the bottom rather than the top like most things that melt, making it near impossible to know just how big they are (so, that’s why the saying it is only the tip of the iceberg came into being.).
Icebergs contain 10% air bubbles, which are released when they melt. The release of air bubbles creates a fizzing sound called Bergie Seltzer. People may use these sounds to study an iceberg’s melting process. However, people are setting themselves up for disappointment if they expect to hear Beethoven’s Moonlight Sinatra; the Bergie Seltzer does not sound like ordinary music and is not worthy of being compared to the masterpiece.
An interesting fact about icebergs is that they are capable of generating energy equivalent to that of an atomic bomb when they break off from a glacier. The force is enough to push the entire glacier backward momentarily. This phenomenon is sometimes referred to as glacial earthquakes (who knew icebergs are that powerful? For a chunk of ice that melts slowly, an iceberg sure packs a punch.).
Hemingway compared his writing style to an iceberg. He believed that the unwritten part of the stories (similar to the submerged part of an iceberg) would affect the readers and have the same impact as the written part. (Authors have a knack for waxing poetry about anything and everything, don’t they? Their imagination and creativity are truly exceptional.)
Some people keep harping about the importance of icebergs as they are a major source of drinking water. However, people find it difficult to grasp the concept as they do not talk about real-life scenarios. So, here are a few facts about icebergs that explain its significance:
- Bottled water consists of meltwater from icebergs. Polewater (a German company) announced its plan to tow icebergs from Antarctica to South Africa in 2019 (too ambitious? Only time will tell.)
- Quidi Vidi Brewing Company’s Iceberg Beer is brewed using icebergs near Newfoundland. Some companies use icebergs to make other alcoholic drinks.
- Iceberg harvesting is taxed (people are already paying for bottled water and now, they have to pay taxes, too?), and a maximum export limit of freshwater was imposed in Newfoundland and Labrador in 2016.
Types Of Icebergs
Any chunk of ice that is larger than a bergy bit (2 – 5m in size) qualifies as an iceberg. The shape of icebergs undergoes several changes during the melting process. Icebergs are classified based on their shapes as follows:
Tabular Icebergs
A tabular berg has a flat top; usually, the icebergs that break off from the ice sheet are tabular. These icebergs are also called the ice islands, as the largest icebergs in the world are usually tabular. Pobeda Ice Island is an example of a tabular iceberg.
Non-Tabular Icebergs
Non-tabular icebergs have irregular shapes, and depending on those shapes, they are classified as follows:
- Domed Iceberg – These icebergs have a smooth and rounded top.
- Sloping Iceberg – Icebergs with an extremely steep side on one end and a smooth slope on the other are called sloping icebergs.
- Pinnacled Iceberg – Icebergs with one or more spires (pointed, slender, and tall structures).
- Dry-docked Iceberg – Icebergs that eroded and formed U-shaped slots or a channel (a landform outlining a shallow water body’s path).
- Weathered Iceberg – Icebergs that weathered the havoc the atmospheric and oceanic elements wrecked.
- Blocky Iceberg – Blocky icebergs resemble (it’s not that hard to guess) a block rather than a sheet of ice.
Main Difference Between Glacier And Iceberg (In Points)
- Glaciers are more permanent, whereas icebergs are temporary bodies of ice.
- Icebergs tend to melt with time. On the other hand, glaciers can grow without melting (however, global warming has raised some serious concerns that glaciers, too, may start melting.), and therefore, they grow over the years.
- Glaciers do not drift or float from the spot in which they formed (though they do keep moving due to their weight). On the contrary, icebergs drift or float with the ocean currents (like toddlers that want to see the world and can’t wait to get out of the house.).
- Icebergs are typically small; however, some icebergs are as large as an island and dwarf small glaciers. On the other hand, glaciers have more or less the same size and shape.
- Glaciers form if the rate of accumulation of snow is greater than the rate of ablation, whereas icebergs calve from glaciers due to high temperatures (that is, increased heat due to direct sunlight or increasing air temperature.).
Conclusion
The International Ice Patrol that was established after The Titanic sank continues today; therefore, people do not have to fear the same fate as those unfortunate passengers at the hands of an iceberg. As for glaciers, people should do their best to reduce or control global warming if they want to save them. The significance of glaciers and icebergs cannot be stressed enough, no matter how many times one speaks about it. Remember, people will suffer greatly if the major freshwater reservoirs melt entirely.
References
- https://oceanwide-expeditions.com/blog/majestic-glaciers-and-icebergs-of-the-arctic-and-antarctica#
- https://education.nationalgeographic.org/resource/iceberg/
- https://en.wikipedia.org/wiki/Iceberg
- https://www.antarctica.gov.au/about-antarctica/ice-and-atmosphere/sea-ice/pack-ice/icebergs/
- https://www.antarcticglaciers.org/glacier-processes/glacier-types/icebergs/
- https://en.wikipedia.org/wiki/Glacier
- https://www.worldwildlife.org/blogs/good-nature-travel/posts/ten-interesting-facts-about-glaciers
- https://eartheclipse.com/science/geology/facts-about-glaciers.html
- https://www.antarcticglaciers.org/glacier-processes/glacier-types/tidewater-glaciers/
