Despite our propensity to consider Earth as static, the is in reality a dynamic and also ever-changing planet. Wind, water, and also ice erode and also shape the land. Volcanic activity and earthquakes alter the landscape in a dramatic and also often violent manner. And also on a much longer timescale, the movement of earth’s plates gradually reconfigures oceans and also continents.

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Each among these procedures plays a duty in the Arctic and Antarctica. We’ll discuss each in general and specifically in the polar regions.


EROSION

Wind, water, and also ice are the 3 agents the erosion, or the moving away that rock, sediment, and also soil. Erosion is identified from weathering — the physics or chemical break down of the minerals in rock. However, weathering and erosion can take place simultaneously. Erosion is a herbal process, despite it is frequently increased by humans’ use of the land. Deforestation, overgrazing, construction, and also road structure often expose soil and also sediments and lead to raised erosion. Extreme erosion leader to ns of soil, ecosystem damage, and a buildup of sediments in water sources. Building terraces and also planting trees can help reduce erosion.

GLACIERS

In the Arctic and also sub-Arctic, glacial erosion has shaped lot of the landscape. Glaciers primarily erode v plucking and also abrasion. Plucking occurs together a glacier flows over bedrock, softening and lifting block of rock that are carried into the ice. The intense push at the basic of the glacier causes some that the ice cream to melt, forming a slim layer that subglacial water. This water flows into cracks in the bedrock. Together the water refreezes, the ice cream acts together a bar loosening the absent by lifting it. The broken rock is for this reason incorporated right into the glacier’s load and is brought along together the glacier gradually moves.


Abrasion happens when the glacier’s ice and rock pieces act together sandpaper, crushing the rock into carefully grained absent flour and smoothing the rock below. Meltwater streams of countless glaciers room grayish in shade due come high quantities of rock flour.
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Mt. Erebus lava lake in 1983. Photograph courtesy that Mt. Erebus Volcano Observatory.


Mt. Erebus is additionally notable for its persistent low-level eruptive activity (with nearly daily eruptions). While the volcano has had actually some background of violent activity, most eruptions room passive lava flows comparable to the volcanoes the Hawaii.

EARTHQUAKES

Seismic activity (earthquakes) is most often connected with tectonic plate boundaries. Together plates slowly move, their jagged edges stick and also suddenly slip, causing an earthquake.

The Gakkel Ridge under the Arctic s experiences tiny earthquakes that accompany the volcanic task found in the area. Antarctica, which lies in the facility of a tectonic plate, does not experience plenty of earthquakes. However, seismic activity is associated with eruptions of Mt. Erebus.


RELATED RESOURCES

Use these resources to learn an ext about erosion, volcanoes, earthquakes, and also plate tectonics and also how these agents of change affect the polar regions.

All about GlaciersLearn exactly how glaciers form, move, and shape the landscape.

Katabatic WindsBasic information around the winds that Antarctica.

National Geographic: pressures of NatureExplore volcanoes and earthquakes in this internet site. Don’t miss out on the interactive activities that permit you to basically erupt volcanoes and trigger earthquakes!

Polar Discovery: Arctic Seafloor ExpeditionDuring summer 2007, a team the scientists provided autonomous underwater vehicles to explore the Gakkel Ridge. The Polar discovery web site papers the expedition and provides lift information, images, and also video.

Mt. Erebus Volcano ObservatoryProvides general information around Mt. Erebus, continuous research, video, and a photo gallery.


National Science education and learning Standards: science Content Standards

The entire National Science education and learning Standards record can be check out online or download for cost-free from the nationwide Academies Press internet site. The complying with excerpt to be taken from thing 6.

A study of changes in the Earth’s surface ar aligns with the planet and space Science, and the science in personal and society Perspectives content standards of the National Science education and learning Standards:

K-4 planet and room Science: alters in the Earth and also Sky

The surface of the earth changes. Some changes are due to slow processes, such together erosion and weathering, and also some changes are as result of rapid processes, such as landslides, volcano eruptions, and earthquakes.

5-8 planet and room Science: structure of the earth System

The solid earth is layered through a lithosphere; hot, convecting mantle; and dense, metallic core.Lithospheric bowl on the scales of continents and also oceans constantly move at prices of centimeters per year in an answer to activities in the mantle. Major geological events, such as earthquakes, volcanic eruptions, and mountain building, an outcome from these plate motions.Land forms are the an outcome of a mix of constructive and also destructive forces. Constructive forces encompass crustal deformation, volcanic eruption, and deposition that sediment, while damaging forces encompass weathering and erosion.

5-8 planet and room Science: earth History

The earth processes we view today, including erosion, movement of lithospheric plates, and also changes in atmospheric composition, are comparable to those that occurred in the past.Fossils carry out important proof of how life and also environmental conditions have changed.

K-4 science in personal and society Perspectives: transforms in Environments

Changes in environments can be organic or affected by humans. Some alters are good, some room bad, and also some are neither good nor bad.Some environmental transforms occur slowly, and others occur rapidly.

5-8 scientific research in an individual and social Perspectives: organic Hazards

Internal and external procedures of the planet system cause natural hazards, occasions that adjust or destroy human and also wildlife habitats, damages property, and also harm or death humans.

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This post was written by Jessica Fries-Gaither. For much more information, check out the Contributors page. Email Kimberly Lightle, primary Investigator, with any kind of questions around the content of this site.