WEBVTT 00:00:00.500 --> 00:00:03.975 Welcome to GCSE A Q A Geography revision. 00:00:04.125 --> 00:00:06.767 Topic G 8: Cold environments. 00:00:06.917 --> 00:00:08.901 This is an optional topic. 00:00:09.051 --> 00:00:12.303 Study it if it is one of the options taught by your school. 00:00:12.453 --> 00:00:17.306 Use your school’s selected case studies if they differ from these revision examples. 00:00:19.967 --> 00:00:27.602 Polar environments occur around the Arctic and Antarctic and have very cold conditions, long dark winters and short summers. 00:00:27.752 --> 00:00:32.691 Antarctica is a continent; the Arctic includes an ocean surrounded by land. 00:00:35.367 --> 00:00:39.086 Tundra lies mainly at high northern latitudes beyond the tree line. 00:00:39.236 --> 00:00:45.017 Its short growing season supports mosses, lichens, grasses and low shrubs rather than tall trees. 00:00:47.667 --> 00:00:53.638 Permafrost is ground that stays at or below 0 degrees Celsius for at least two consecutive years. 00:00:53.788 --> 00:00:57.625 The active layer above it thaws in summer and refreezes in winter. 00:00:57.775 --> 00:00:59.845 Active layer and permafrost. 00:00:59.995 --> 00:01:01.787 Layer thickness varies. 00:01:01.937 --> 00:01:05.968 Permafrost is frozen ground and may include soil, rock and ice. 00:01:10.633 --> 00:01:17.054 Low temperatures slow decomposition, so dead material breaks down slowly and nutrient cycling is slow. 00:01:17.204 --> 00:01:24.221 Frozen ground limits rooting depth; summer melt can leave waterlogged soils because water cannot drain through permafrost. 00:01:26.900 --> 00:01:31.088 Climate, frozen ground, soils and vegetation are closely linked. 00:01:31.238 --> 00:01:37.636 Warming can thaw permafrost, change drainage and damage buildings while also changing plant communities. 00:01:40.300 --> 00:01:44.147 Low-growing plants avoid strong winds and grow near warmer ground. 00:01:44.297 --> 00:01:49.044 Some have small hairy leaves or rapid summer growth to make use of the short season. 00:01:51.700 --> 00:01:58.054 Thick fur, fat layers, migration and seasonal changes in coat colour help different animals survive. 00:01:58.204 --> 00:02:03.323 Adaptations vary between species; not every Arctic animal has every feature. 00:02:06.000 --> 00:02:11.451 Biodiversity is limited by harsh conditions, and food webs can be relatively simple. 00:02:11.601 --> 00:02:16.902 Damage to vegetation may recover slowly because growth and decomposition are slow. 00:02:19.567 --> 00:02:22.731 Cold regions may contain oil, gas and minerals. 00:02:22.881 --> 00:02:30.901 Extraction can create jobs, tax revenue and energy supplies, but pollution is difficult to clean up and habitats can be disturbed. 00:02:33.567 --> 00:02:36.935 Fishing supports livelihoods in productive northern seas. 00:02:37.085 --> 00:02:42.982 Overfishing and bycatch can damage ecosystems, so catch limits and monitoring are important. 00:02:45.633 --> 00:02:50.251 Tourism brings income from wildlife, landscapes and outdoor activities. 00:02:50.401 --> 00:02:56.106 Visitors, ships and new facilities can disturb animals and increase waste or accident risks. 00:02:58.767 --> 00:03:04.441 Extreme cold makes work harder and requires insulation, protective equipment and more energy. 00:03:04.591 --> 00:03:08.001 Winter darkness and severe weather can interrupt transport. 00:03:10.667 --> 00:03:16.777 Remote locations and long distances make supplies, emergency care and construction expensive. 00:03:16.927 --> 00:03:20.772 Ice and seasonal thaw can restrict when equipment can be moved. 00:03:23.433 --> 00:03:28.254 Buildings and roads on permafrost need designs that limit warming of the ground. 00:03:28.404 --> 00:03:33.981 If frozen ground thaws, uneven subsidence can crack foundations and damage pipelines. 00:03:36.633 --> 00:03:46.115 Cold environments have wilderness value: extensive areas with limited human modification, distinctive wildlife and opportunities for scientific research. 00:03:46.265 --> 00:03:51.162 They also have cultural value and are homes to Indigenous peoples in the Arctic. 00:03:53.833 --> 00:04:02.066 Fragile habitats need protection because damage may last for decades and species depend on linked feeding grounds or migration routes. 00:04:02.216 --> 00:04:06.275 Wilderness does not mean an area has no inhabitants or human history. 00:04:08.933 --> 00:04:17.604 Technology can reduce impacts through insulated or raised pipelines, carefully designed foundations, leak monitoring and seasonal access routes. 00:04:17.754 --> 00:04:20.985 It reduces risks but cannot remove them completely. 00:04:23.667 --> 00:04:30.588 Governments can create protected areas, require environmental assessments and regulate extraction or tourism. 00:04:30.738 --> 00:04:35.526 Enforcement and consultation with residents affect whether these measures work. 00:04:38.200 --> 00:04:41.409 International agreements can protect shared environments. 00:04:41.559 --> 00:04:52.576 The Antarctic Treaty System supports peaceful scientific cooperation, and its environmental protocol prohibits mineral resource activities other than scientific research. 00:04:55.233 --> 00:05:01.291 Antarctic agreements do not govern the Arctic, where countries have sovereignty over land and parts of the sea. 00:05:01.441 --> 00:05:06.423 Arctic conservation involves national laws, cooperation and community rights. 00:05:09.100 --> 00:05:14.433 Conservation groups can monitor wildlife, campaign for protection and support research. 00:05:14.583 --> 00:05:23.071 Balancing development and conservation requires considering income, local needs, long-term environmental damage and alternatives. 00:05:25.733 --> 00:05:35.971 Alaska contains tundra, polar and other environments; this case study focuses on its cold northern areas while recognising that not all of the state is treeless tundra. 00:05:36.121 --> 00:05:39.065 Permafrost and remoteness constrain development. 00:05:41.733 --> 00:05:46.776 Oil and gas from the North Slope, including Prudhoe Bay, supply energy and income. 00:05:46.926 --> 00:05:54.145 The Trans-Alaska Pipeline carries oil south to Valdez, showing how infrastructure connects remote extraction to markets. 00:05:56.800 --> 00:06:02.655 Mining, including zinc extraction at Red Dog in northwest Alaska, creates jobs and exports. 00:06:02.805 --> 00:06:07.965 Access roads, transport and waste management increase costs and can affect habitats. 00:06:10.633 --> 00:06:17.595 Fishing in Alaska's surrounding seas provides food, employment and exports, including pollock, salmon and crab fisheries. 00:06:17.745 --> 00:06:23.919 Fish stocks need management, and this marine activity should not be confused with fishing on the tundra itself. 00:06:26.600 --> 00:06:32.284 Tourism includes wildlife viewing, outdoor recreation and visits to protected landscapes. 00:06:32.434 --> 00:06:39.429 Gates of the Arctic has no road network for visitors, illustrating both wilderness appeal and the challenge of access. 00:06:42.100 --> 00:06:48.023 Cold, darkness, long distances and frozen ground make construction and supplies expensive. 00:06:48.173 --> 00:06:54.529 Permafrost thaw can damage roads and foundations, while spills are difficult to clean up in remote locations. 00:06:57.200 --> 00:07:04.761 Protected areas and environmental rules limit some development, while carefully designed infrastructure can reduce disturbance. 00:07:04.911 --> 00:07:12.686 Decisions involve Indigenous and other local communities whose livelihoods include both paid employment and subsistence use. 00:07:15.367 --> 00:07:20.443 Alaska shows a tension between resource income and protection of fragile habitats. 00:07:20.593 --> 00:07:28.161 A scheme should be judged by local benefits, long-term risks, enforcement and whether less damaging alternatives are practical. 00:07:30.833 --> 00:07:33.052 That completes Cold environments. 00:07:33.202 --> 00:07:36.547 Revisit the notes and test yourself on the revision website.