The Spectrum of management Population densities in an area will always affect the level of protection that can be afforded – Antarctica vs. Lake District for example. Stakeholders (players) help conserve and protect landscapes (e.g. Friends of the Lake District) and...
Natural Threats Avalanches An avalanche is a sudden downhill movement of snow. Two types- ‘Loose snow’ and ‘Slab avalanches’. A Slab avalanche is the most dangerous form of movement they can be caused by: • Heavy snowfall • Deforestation, making the slopes less stable...
Wilderness There are two types of wilderness they consist of: active and relict landscapes, which can be characterised by the following: Active- • Tend to be remote regions • Consist of a harsh physical environment • Are sparsely populated (indigenous populations)....
Water Movement within the Glacier System - Glacier hydrology is the study of the flow of water through glaciers. - Water running on the surface of the glacier can disappear through cracks and holes in the glaciers and powerful rivers can later emerge from the glacier...
Glacial Deposition Processes There are two principle depositional processes: Lodgement Occurs beneath the ice mass when subglacial debris, being carried, becomes ‘lodged’ or stuck on the glacier bed. It occurs when friction is greater than the drag force of the...
Erosional Processes There are two main erosional processes that you need to be able to explain and then link to different landforms: Abrasion – when sub-glacial basal ice rubs against the bedrock and valley sides. This causes the wearing away of the landscape as the...
Glacial Erosion Processes There are two types of glacial erosion: Abrasion Occurs when rocks and stones become embedded in the base and sides of the glacier. These are then rubbed against the bedrock (at the bottom of the glacier) and rock faces (at the sides of the...
Glacial Movement Glacier movement is not constant over time, or even through the glacier itself. Factors Affecting Rate of Movement: Thickness: a glacier moves because pressure generated by its own weight causes it to deform and/or slide, consequently, thick glaciers...
Formation of Glaciers - Snow accumulates and compacts into an upland nivation hollow. - Over 3-4yrs, water is squeezed out of the ice, percolates down and refreezes onto the bottom of the glacier (firn/nevé). - Gravity and the weight of the ice above will gradually...
The Cryosphere • Consists of ice sheets and glaciers, combined with sea ice • Parts of Earth’s crust and atmosphere subject to temperatures below 0 degrees C for at least part of the year Ice Coverage • Ice cover at Pleistocene maximum was more than 3X greater than...
Periglacial Environments: a cold climate, typically near glacial regions. The periglacial environment is a cold climate, often marginal to (next to) the glacial environment, and is subject to intense cycles of freezing and thawing Permafrost Environments: where the...
Glacier - A slowly moving mass or river of ice formed by the accumulation and compaction of snow on mountains or near the poles. Ice Cap - Mass that covers less than 50,000 km² of land area (usually covering a highland area). E.g Iceland Ice Sheet - Mass of glacier...
Abrasion- rock and sediment smash and grind against rocks and cliffs, breaking bits off and smoothing surfaces. Hydraulic action- air in cracks in cliffs is compressed when waves crash in. The pressure exerted by the compressed air break off pieces of rock....
The energyprovided by waves, tides and currents transports eroded material. There are four transportational processes: Traction- very big rocks/boulders are rolled along the sea bed by the force of the water. Saltation- pebbles and gravel are bounced along the sea bed...
Deposition- when material being transported is dropped on the coast. Marine deposition- when sediment carried by seawater is deposited. Aeolian deposition- when sediment carried by wind is deposited. Happens when the sediment loadexceeds the ability of the water or...
Sub-aerial weatheringthe gradual break down of rock by agents such as ice, salt, plant roots and acids. Weathering weakens cliffs and makes them more vulnerable to Salt Weathering Caused by saline water. Enters pores/cracks at high tide. Tide goes out, rocks...
Cliffs and Wave-cut Platforms Cliffs- form as the sea erodes the land. They retreat due to the action of waves and weathering. Weathering and wave erosion cause a notch to form at the high-water mark - a cave is formed. Rock above becomes unstable and collapses....
Beaches Form when constructive waves deposit sediment on the shore. Shingle beachesare steep and narrow; have large particles. Sand beachesare wide and flat; have small particles. Berms- ridges of sand and pebbles found at high tide marks. Runnels- grooves in the sand...
Eustatic sea level change - caused by a change in the volume of water in the sea, or by a change in the shape of the ocean basins. Causes: Climate change. Tectonic movements. Isostatic sea level change - caused by vertical movements of the land relative to the sea....
Last century: global temperature has increased rapidly - global warming. Temperature increase has been very fast; changes in climate are a result of human activities. Activities increase the concentration of greenhouse gases in the atmosphere. Concentration increases,...
Storms are likely to be more frequent and more intense. More frequent and more severe coastal flooding of low-lying areas. Submergence of low-lying islands. Changes in the coastline, islands are created. Contamination of water sources and farmland - salt water may...
Rias: Formed where river valleys are partially submerged. Gentle, long- and cross-profiles. Wide and deep at their mouth. Fjords: Drowned glacial valleys rather than drowned river valleys. Straight and narrow with steep sides. Shallow mouth formed by deposition of...
Aims Protect homes. Protect businesses. Protect the environment from erosion & flooding. Flooding and erosion of the coastline can have severe social, economic and environmental impacts. All coastal settlements want to be defended, but the amount of money...
Sea wall- reflects waves back out to sea, preventing erosion and flooding, expensive creates a strong backwash which erodes under the wall. Revetment- slanted structures built at the foot of cliffs; waves break against them which reduces their power, expensive to...
Beach nourishment- sand and shingle are added to beaches from elsewhere to create wider beaches to reduce erosion of cliffs. Beach stabilisation- reducing the slope angle and planting vegetation, or by sticking stakes and old tree trunks in the beach to stabilise the...
Strategies used shouldn't cause too much damage to the environmentor to people's homes and livelihoods and shouldn't cost too much. Hard engineering is often expensive,and it disrupts natural processes. Soft engineering schemes tend to be cheaperand require less...
Inputs of Sediment into the System Rivers carry sediment from inland. Sea level rise can flood river valleys, forming estuaries. Eroded material from cliffs by waves, weathering and landslides. Waves, tides and currents can transport sediment into the coastal zone...
Inputs- sediment; energy from wind, waves, tides and currents. Outputs- sediment can be transported at sea or deposited further down. Flows/transfers- erosion, weathering, transportation and deposition occur. Stores/components- landforms are stores of sediment....
Wind Created by air moving from areas of high pressure to low pressure. Storms - pressure gradient is high and so strong winds. Generate powerful waves. Waves Created by the wind blowing over the surface of the sea. Friction gives its circular motion. Height is...
High Energy Coasts Receive high inputs of energy in the form of large, powerful waves. Caused by strong winds, long fetches and steeply shelving offshore zones. Sandy coves and rocky landforms. Erosion is higher than deposition. Low Energy Coasts Receive low inputs of...