If you have not already, go check out the other article: “Hydrology...Oceanography...Limnology...Glaciology! Oh, too many to count! - Introduction to Glaciology” before coming to this one! That gives an introduction to glaciology while this article provides a more in-depth view of the field. The introduction article ended with an overview of how global warming is connected to glaciology.

In the last article, you learned about glaciers and how they form, where they are found, and how they are classified. However, glaciology is not limited to the study of glaciers, it encompasses all ice forms. Because there are so many to talk about, we will only be discussing a few others here, but feel free to research on your own and discover more about this cool field of study!

Another type of ice formation is an ice cap. Ice caps are actually often bigger than glaciers, so they can reach incredible weights. The force from their weight on the land allows them to flow. The center of an ice cap or ice sheet has an ice dome while the outside of the cap is made of smaller ice shelves and outlet glaciers. The ice dome is just a thick symmetrical collection of ice that often looks like a bowl. Meanwhile, the outlet glacier is a stream of ice coming from the ice dome. Ice shelves will extend into the ocean and look like cliffs of ice. They can be super high, even nearly 100 feet up in the air! Ice fields are similar to these ice caps, but they do not typically have ice domes, and they may have fewer ice shelves. These are typically smaller but do not underestimate them. There are historical scientific records of ice fields as large as some continents!

Although ice caps and fields are clearly impressive, the most astounding of ice structures is an ice sheet. An ice sheet is an extension of ice spreading from the inside out. They are also made of many ice domes and outlet glaciers, and they have ice shelves on the exterior. A big difference between these ice sheets and ice caps is that ice sheets put pressure on Earth, so if an ice sheet melts, Earth’s crust will rise in the melted area. These sheets are typically a minimum of 19,300 square miles (almost the size of what you could get if you put 13 copies of the state of Rhode Island and placed them next to each other)! There are a lot of impressive ice sheets, but one of the most incredible include the Antarctic ice sheets covering the majority of Antarctica. The sheet is the size of the United States, Mexico, and Central America combined! Crazy right? We know this because sometimes scientists can travel to it for temporary study missions. However, because of the terribly cold and dangerous conditions, no one can live on the ice sheet.

An interesting piece of information that is not a part of glaciology, but is still fun to know, is that Antarctica also does have several miles of ice-free spaces. In these spaces, you can see rocks underneath the normal Antarctic surface! These areas are called “dry valleys” and it is estimated that it has not rained or snowed in these regions for at least a million years because winds keep the air incredibly dry and cause snow to evaporate before touching the ground. Here, nothing decomposes, everything remains completely intact. Due to this, if the lands were in hotter areas of the world, they would be much more dangerous than even the Sahara desert!

Going back to glaciology, you may be wondering why the rocks underneath Antarctica can only be seen in these dry valleys. It is because the ice on the rocks is normally extremely thick. In fact, across the continent, ice has an average depth of over a mile, and can even get to be two miles thick. This causes Antarctica to have an elevation level that makes it very difficult to be inhabited. Glaciologists have taken deep ice-core samples in Antarctica (vertical sections of the ice) to help determine what the climate was like in history. These samples show that over the past 160,000 years, Earth has had climate patterns connected to carbon dioxide and methane in the atmosphere. This supports theories of global warming, especially because scientists have seen patterns that represent an increase in warm temperatures over the past couple of centuries. Because of its incredible thickness, the ice weighs down the ground underneath it. If the ice melted, the land would pop up and raise global sea levels by approximately 200 feet, flooding all ports and places with low land including New York City and America’s Eastern seaboard. Even only 10% of the ice melting would raise the sea level by 20 feet and cause damage. This is a major reason why we need to fight against global warming and protect our environment!! Next time you and your friends plan to go somewhere, try to carpool. If your parents ask if they can drive you to school, ask if you can walk or take the bus instead. Make sure to practice safe habits like looking both ways when you cross the street and not talking to strangers, but even small practices like this can have a grand impact on the longevity of our world.