WEBVTT 00:00:00.500 --> 00:00:03.975 Welcome to GCSE A Q A Geography revision. 00:00:04.125 --> 00:00:07.469 Topic G 12: Glacial landscapes in the UK. 00:00:07.619 --> 00:00:09.603 This is an optional topic. 00:00:09.753 --> 00:00:13.004 Study it if it is one of the options taught by your school. 00:00:13.154 --> 00:00:18.007 Use your school’s selected case studies if they differ from these revision examples. 00:00:20.667 --> 00:00:27.736 During the last ice age, much of Scotland, Wales, northern England and Northern Ireland was covered by ice at different times. 00:00:27.886 --> 00:00:37.505 At its maximum around 27,000 years ago, the British to Irish Ice Sheet extended beyond today's coastline; southern England was largely outside it. 00:00:40.167 --> 00:00:43.546 A glacier is a mass of ice that moves under its own weight. 00:00:43.696 --> 00:00:52.020 Snow accumulates and is compressed into ice; movement involves deformation of the ice and, where conditions allow, sliding at its base. 00:00:54.700 --> 00:00:59.670 Freeze to thaw weathering happens when water enters rock cracks, freezes and expands. 00:00:59.820 --> 00:01:06.881 Repeated cycles can break off fragments; it needs temperatures to cross freezing, not permanently frozen conditions. 00:01:09.533 --> 00:01:16.497 Abrasion occurs when rocks carried in the glacier's base scrape the bedrock, smoothing it and leaving scratches called striations. 00:01:19.167 --> 00:01:24.765 Plucking happens where meltwater freezes around cracked rock and moving ice pulls fragments away. 00:01:24.915 --> 00:01:28.763 The glacier can then use these fragments to abrade other surfaces. 00:01:31.433 --> 00:01:36.213 Rotational slip is curved movement of ice in a corrie, helping deepen its hollow. 00:01:36.363 --> 00:01:39.964 Bulldozing pushes loose sediment in front of advancing ice. 00:01:42.633 --> 00:01:46.434 Glaciers carry debris on their surface, within the ice and at the base. 00:01:46.584 --> 00:01:50.669 Debris comes from weathering on valley sides and erosion beneath the glacier. 00:01:53.333 --> 00:01:56.627 When ice melts it leaves unsorted sediment called till. 00:01:56.777 --> 00:02:04.723 Meltwater deposits outwash, which is more often sorted and layered because flowing water transports different particle sizes differently. 00:02:07.400 --> 00:02:10.461 A corrie begins as a hollow where snow accumulates. 00:02:10.611 --> 00:02:18.993 Ice movement, plucking and abrasion deepen it; rotational movement and less erosion at the edge leave a steep back wall, deep basin and rock lip. 00:02:19.143 --> 00:02:20.581 Ice in a corrie. 00:02:20.731 --> 00:02:24.204 Curved ice movement, abrasion and plucking deepen the hollow. 00:02:24.354 --> 00:02:28.235 After melting, a tarn may occupy the basin; not to scale. 00:02:32.900 --> 00:02:36.215 After ice melts, a tarn may occupy the corrie basin. 00:02:36.365 --> 00:02:38.541 Not every corrie contains a lake. 00:02:41.200 --> 00:02:45.367 An arête is a narrow ridge between neighbouring corries or glacial valleys. 00:02:45.517 --> 00:02:51.052 A pyramidal peak forms where several corries erode back towards a summit from different sides. 00:02:53.733 --> 00:03:00.100 A glacial trough is a broad valley with steep sides and a relatively flat floor, often described as U-shaped. 00:03:00.250 --> 00:03:04.213 A glacier widens, deepens and straightens a former river valley. 00:03:06.867 --> 00:03:12.519 Truncated spurs are steep valley-side ends where ice has cut through former interlocking spurs. 00:03:12.669 --> 00:03:16.726 They help distinguish a glacial trough from a river's V-shaped valley. 00:03:19.400 --> 00:03:24.475 A hanging valley is a smaller tributary valley left above a deeply eroded main trough. 00:03:24.625 --> 00:03:28.155 A stream may fall as a waterfall where it joins the main valley. 00:03:30.833 --> 00:03:35.698 A ribbon lake is a long narrow lake in an over-deepened section of a glacial valley. 00:03:35.848 --> 00:03:44.497 Differential erosion of less resistant rock or changes in ice thickness can create the basin, sometimes held by a rock or moraine barrier. 00:03:47.167 --> 00:03:52.455 An erratic is a boulder transported by ice and deposited on different local bedrock. 00:03:52.605 --> 00:03:56.366 Its rock type can help show the direction from which the ice travelled. 00:03:59.033 --> 00:04:04.589 Drumlins are streamlined hills made largely of glacial sediment, shaped beneath moving ice. 00:04:04.739 --> 00:04:11.874 Their long axes broadly indicate ice-flow direction; formation is more complex than simply dropping a pile of stones. 00:04:14.533 --> 00:04:17.627 Lateral moraine accumulates along a glacier's sides. 00:04:17.777 --> 00:04:23.738 Medial moraine forms where the lateral debris of joining glaciers combines, leaving a band down the middle. 00:04:26.400 --> 00:04:32.255 Terminal moraine marks a former glacier limit, and recessional moraines mark pauses during retreat. 00:04:32.405 --> 00:04:35.839 Ground moraine is debris spread across the former glacier bed. 00:04:38.500 --> 00:04:43.757 Glaciated uplands offer tourism through dramatic scenery, lakes, walking and climbing. 00:04:43.907 --> 00:04:49.644 Farming often includes sheep grazing, while forestry and quarrying use land and natural resources. 00:04:52.300 --> 00:04:56.685 Tourism creates jobs and supports shops, accommodation and transport. 00:04:56.835 --> 00:05:03.639 Seasonal demand can make employment insecure, and busy periods can increase congestion and pressure on services. 00:05:06.300 --> 00:05:11.067 Second homes or holiday lets can raise housing pressure in some communities. 00:05:11.217 --> 00:05:17.231 Visitors may also support local culture and fund conservation, so impacts are not all negative. 00:05:19.900 --> 00:05:24.977 Walkers can erode paths and disturb wildlife; traffic adds noise and emissions. 00:05:25.127 --> 00:05:32.581 Quarrying provides materials and jobs but changes scenery, creates dust and can conflict with tourism or conservation. 00:05:35.233 --> 00:05:41.377 Forestry can provide timber and employment, but planting choices affect habitats and landscape character. 00:05:41.527 --> 00:05:48.289 Farming maintains livelihoods and some valued landscapes, while heavy grazing can restrict vegetation recovery. 00:05:50.967 --> 00:05:55.888 Path repair, drainage and directing walkers onto durable routes reduce erosion. 00:05:56.038 --> 00:06:03.450 Restricting access in sensitive places may protect habitats but needs clear explanation and practical alternatives. 00:06:06.100 --> 00:06:10.562 Public transport, park-and-ride and suitable parking can reduce traffic. 00:06:10.712 --> 00:06:15.564 Services need funding and must be frequent enough for visitors and residents to use. 00:06:18.233 --> 00:06:24.981 Visitor information, ranger work and codes of conduct can reduce litter, disturbance and unsafe behaviour. 00:06:25.131 --> 00:06:30.773 Conservation organisations and local businesses can work together on long-term management. 00:06:33.433 --> 00:06:40.323 Planning controls and protected-area management aim to balance conservation, local livelihoods and recreation. 00:06:40.473 --> 00:06:46.423 Evaluate a named area's strategy using evidence about both benefits and remaining conflicts. 00:06:49.100 --> 00:06:55.115 The Lake District in northwest England contains glacial troughs, corries, narrow ridges and long lakes. 00:06:55.265 --> 00:07:01.675 Its landscape reflects repeated glaciation, the underlying rocks and later river and slope processes. 00:07:04.333 --> 00:07:07.107 Red Tarn lies in a corrie beneath Helvellyn. 00:07:07.257 --> 00:07:13.943 Striding Edge is a sharp ridge beside it, while valleys such as Great Langdale show glacial widening and steep sides. 00:07:16.600 --> 00:07:21.075 Long lakes such as Ullswater and Windermere occupy glacially shaped valleys. 00:07:21.225 --> 00:07:28.113 Ice transported and deposited debris across the region, leaving glacial sediments as well as erosional landforms. 00:07:30.767 --> 00:07:36.270 Near Keswick, till in the Thornsgill and Mosedale valleys records deposition by former ice. 00:07:36.420 --> 00:07:44.119 Shap Granite erratics carried beyond their source in the eastern Lake District show how rock type can provide evidence of ice transport. 00:07:46.800 --> 00:07:51.809 Lakes, mountain scenery, walking routes, climbing and cultural attractions draw visitors. 00:07:51.959 --> 00:07:58.964 Tourism supports accommodation, shops, boat services and guides, alongside farming and other local activities. 00:08:01.633 --> 00:08:05.700 Busy routes suffer trampling, vegetation loss and soil erosion. 00:08:05.850 --> 00:08:13.986 Rainwater then deepens damaged paths; walkers avoiding muddy sections can widen the scar, affecting both scenery and habitats. 00:08:16.667 --> 00:08:20.944 Traffic and parking pressure can disrupt residents and increase emissions. 00:08:21.094 --> 00:08:27.835 Tourism supports income, but seasonal jobs and housing pressures mean the benefits and costs are unevenly shared. 00:08:30.500 --> 00:08:36.131 Fix the Fells repairs and maintains upland paths using stone work, drainage and regular care. 00:08:36.281 --> 00:08:42.072 This keeps foot traffic on more durable routes and reduces sediment being washed into rivers and lakes. 00:08:44.733 --> 00:08:49.608 Visitor information and public transport can help reduce traffic and disturbance. 00:08:49.758 --> 00:08:57.661 Effective management needs funding, cooperation with residents and businesses, and continued maintenance as visitor use and weather change. 00:09:00.333 --> 00:09:06.316 Path repairs help conservation and continued access, but they do not remove all tourism impacts. 00:09:06.466 --> 00:09:13.207 Evaluate the Lake District by linking a specific measure to the problem it addresses and the limitations that remain. 00:09:15.867 --> 00:09:18.640 That completes Glacial landscapes in the UK. 00:09:18.790 --> 00:09:22.135 Revisit the notes and test yourself on the revision website.