Why continental glaciers smooth the landscape

Geologists study moraines to figure out how far glaciers extended and how long it took them to melt away. Moraines are named by their location relative to the glacier:. Usually drumlins are found in groups called drumlin fields. While glaciers dump unsorted sediments, glacial meltwater can sort and re-transport the sediments Figure below.

A broad area of stratified drift from meltwater over broad region is an outwash plain. Several types of stratified deposits form in glacial regions but are not formed directly by the ice. Varves form where lakes are covered by ice in the winter. Dark, fine-grained clays sink to the bottom in winter but melting ice in spring brings running water that deposits lighter colored sands. If during a year, a glacier accumulates more ice than melts away, the glacier advances downhill.

If a glacier melts more than it accumulates over a year, it is retreating Figure below. Skip to main content. Search for:. Roche moutonnee is visible in many hilly areas as outcroppings of flat rock. In contrast to alpine glaciers, ice sheets do not create landscape features as they spread.

They tend to smooth out the land beneath them. Glaciers provide people with many useful resources. Glacial till provides fertile soil for growing crops. Deposits of sand and gravel are used to make concrete and asphalt. The most important resource provided by glaciers is freshwater. Many rivers are fed by the melting ice of glaciers. The Ganges is the most important source of freshwater and electricity in India and Bangladesh. Electricity is created by dams and hydroelectric power plants along the Ganges.

Some companies link glacial water to clean, fresh taste. Because water has been trapped in the glacier for so long, many people believe it has not been exposed to pollutants that liquid water is exposed to. The dramatic, diverse landscape of Yosemite Valley, California, was sculpted entirely by glaciers during the last Ice Age. Threats to Glaciers The processes that remove snow, ice, and moraine from a glacier or ice sheet are called ablation.

Ablation includes melting, evaporation, erosion, and calving. Glaciers melt when ice melts more quickly than firn can accumulate. Glaciers are important indicators of global warming and climate change in several ways.

Melting ice sheets contribute to rising sea levels. As ice sheets in Antarctica and Greenland melt, they raise the level of the ocean. Tons of fresh water are added to the ocean every day. Large icebergs created by such an event create hazards for shipping.

Large additions of fresh water also change the ocean ecosystem. Organisms, such as many types of corals, depend on salt water for survival. Some corals may not be able to adjust to a more freshwater habitat. The loss of glacial ice also reduces the amount of fresh water available for plants and animals that need fresh water to survive. Glaciers near the Equator , such as those on the tropical island of Papua or in South America, are especially at risk.

The residents below Chacaltaya Glacier in Bolivia, for instance, depended on the glacier for almost all of their fresh water and electricity. In , Chacaltaya Glacier melted entirely. A few glaciers may actually be benefiting from global warming.

Glaciers are growing quickly there. Less precipitation also affects some glaciers. This reduction is the result of few heavy snowfalls. Why So Blue? Some glaciers and icebergs are blue, for the same reason water is blue. The chemical bond between oxygen and hydrogen in water absorbs light in the red end of the visible light spectrum. Blue glaciers and icebergs are not blue for the same reason the sky is blue. The sky is blue due to atmospheric scattering of light Raleigh scattering , a different phenomenon.

Siachen Glacier is the worlds highest area of conflict. Although India controls Siachen, both India and Pakistan claim the area as part of their country. Siachen Glacier is the site of the worlds highest helicopter landing pad, which India built for military and emergency use. Icefall Glaciers are called "rivers of ice. Ice flows down the icefall just like water falls down a waterfall.

The Khumbu Icefall is one of the most difficult terrains on Mount Everest. Paleoclimatology Paleoclimatology is the study of the Earth's atmosphere in prehistoric times. Paleoclimatology depends on ice and bubbles in glaciers and ice sheets.

Scientists extract long tubes of ice, called ice cores, from thick ice sheets, usually in the Antarctic. Ice cores are layered, with the deepest ice having the oldest information.

Wide bands indicate a heavy snowfall. Darkly colored bands indicate smoke or other chemicals in the atmosphere. Ice cores can measure the state of the atmosphere as far back as 80, years. For instance, cores from ice sheets from the year contained chemicals from the massive eruption of Krakatoa, a volcanic island in Indonesia. Ice cores showed those chemicals drifted from the South Pacific to Antarctica and Greenland and stayed in the atmosphere for many years afterward.

Also called the Ganga. Also known as a pyramidal peak. Explain why continental glaciers smooth the landscape and alpine glaciers create a rugged landscape? How is the landscape carved by alpine glaciers? What glaciers create cirques on sides of mountains? What type of glaciers can create cirques on the side of mountains? What do glaciers create? Is a glaciers a mager land form? What types of landforms do glaciers create?

What landforms do glaciers create? How great lakes were create? What are two landforms that can be caused by glaciers? How did glaciers create landforms in NY? Can a cyclone create continental drift? What creates a continental rise? Landscape Materials? Did glaciers carve basins that filled with water to create lakes? When sediments fall out a glaciers they create a deposit called? What do glaciers and landslides tend to create? When glaciers drag attached rocks across the land they?

When glaciers drag attached rocks across the land? Sediments are scraped away then the exposed bedrock is carved and polished by the passing ice. This happens much faster if there are lots of rocks and sand poking out from the bottom of the ice.

Small flakes of rock can be removed by the ice forming small chattermarks or larger crescentic gouges and fractures. Glacial ice and meltwater can also carve out grooves and furrows. Some are lined up in the direction the ice flowed but sometimes they curve and bend. To be the provider of geoscience data globally Navigation Main content Bottom links. What is geology?