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Deserts Formandthephysical That Createtheconditionsinwhich Focus Ontheclimaticextremes Living Indesertareas Chapter focus 7 Learning focus Deserts Deserts are sparse and extreme. Unlike rainforests and coral reefs, life struggles to exist. Human impact is limited but well adapted to the harsh conditions. At the other Deserts are stark but spectacular Geographical tools end of the atmospheric movements environments, portrayed in books and motion pictures as places of adventure and Maps that create the conditions suitable mystery. They have very little precipitation • use various types of maps for tropical rainforests, the and high levels of evaporation, leading • locate features using latitude and longitude, plants and animals of the desert to scattered vegetation and highly area and grid references live with little of Earth’s most adapted flora and fauna. Almost one • identify physical and cultural features on a Definitions map important compound—water. The third of Earth’s land surface is classified aeolian—processes to do with the wind GLOBAL ENVIRONMENTS • measure distances on a map using linear arable—land that is capable of growing crops as arid or semi‑arid desert. This global scale adaptations and ingenuity of its arid—dry, parched climate or land environment is located on every continent inhabitants make deserts fascinating • use the points of the compass to determine atmospheric pressure—the weight of the air on the environments to study. except Europe. Geographers study direction Earth’s surface the geographical processes in desert • identify and interpret relief desertification—the spread of desert lands and land Students can get a sense of the degradation across more arable land environments and the adaptations people • construct a sketch map desert through some of the many ecosystem—a community of organisms interacting with one have made to live in them. Graphs and statistics another and with the environment in which they live movies using the desert as their • identify and calculate maximum and evaporation—the process by which water turns from liquid backdrop. Some films, such as The minimum, total, range, rank and average to vapour • construct and interpret bar, column, climatic nomadic—a lifestyle where people move around an Gods Must Be Crazy and Walkabout environment to a range of locations, usually related to the Syllabus outcomes and proportional graphs also give a glimpse of the life and seasons and the availability of food A student: Photographs oasis—an area in the desert where groundwater is close to character of the indigenous people the surface and plants can grow 4.1 identifies and gathers geographical information • draw a line drawing playa—a flat basin in the desert that is covered in water every living in desert areas. • collect and interpret photographic images 4.2 organises and interprets geographical so often To study deserts, students will information • distinguish between oblique, aerial, ground‑ salinisation—the process by which soil and water become focus on the climatic extremes 4.3 uses a range of written, oral and graphic forms level photographs and satellite imagery salty due to salts moving in soils to communicate geographical information ICT semi-arid—the transition zone between desert and grassland that create the conditions in which that receives an average 250–500 millimetres of rain per year 4.4 uses a range of geographical tools • collect and interpret electronic information deserts form and the physical subsistence—crops or food grown to satisfy a community 4.6 describes the geographical processes that • design and create a multimedia presentation and not for sale processes that shape the desert form and transform environments subtropical—climates close to the Tropics of Cancer and landscape. Life is simple but 4.8 describes the interrelationships between Capricorn but not between them delicate, with each plant and people and environments sustainable—using resources in a way that does not degrade 4.10 explains how geographical knowledge, them animal depending on only a few understanding and skills combine with wadi—a stream or river course in a valley of a desert others for survival. Human impacts, knowledge of civics to contribute to informed xerophyte—a plant adapted to living in the desert or in citizenship drought directly through activities such as mining, or indirectly through climate change, can have marked effects on the environment. ICT/Research skills Sample pages The year 2006 was designated by the United Nations to be the International Year of Deserts and Desertification. World Environment Day 2006 was therefore dedicated to raising the awareness of the environmental issues facing desert regions and the large numbers of people who live in these areas. Look up the United Nations Environment Programme website at http://www. unep.org/wed/2006/english/Information_Material/index.asp and have a look at the multimedia presentation on the issue of deserts and desertification. This short film shows some graphic images on the environmental and human issues facing many of the desert regions of the world. The website also features other presentations, booklets and posters that can be used as stimulus material. They are free to download for non-commercial, educational purposes. Chapter 7 Deserts 157 ARCTIC OCEAN 1 662°N Siberia Arctic 7.1 7.4 The global distribution of desert environments Circle Focus 7.1 World deserts Kara Kum Syrian Gobi ATLANTIC OCEAN Answers to Desert Chihuahuan Desert Deserts are spread around the world. Negev Taklimakan Great activities 1 Basin 232°N Sahara Thar Desert Tropic of They are found in all continents and their people Desert Sonoran Cancer Desert Mojave except Europe. The people who Libyan Rub’ al-Khali Desert Peruvian Knowledge 0° Desert Nubian PACIFIC OCEAN Desert Equator make their homes in these harsh Deserts cover about 30 per cent of Earth’s land surface Desert SOUTH 1 Deserts are environments that and their area is increasing. They cover parts of at least environments are equally diverse. Great Sandy Desert AMERICA 40 countries. All deserts have low rainfall but they are 1 Tanami Desert Atacama receive low rainfall. They can 232°S Tropic of Many of these groups have been the not all the same in appearance—there are different Desert Namib INDIAN OCEAN Simpson Desert Capricorn be cold or hot, but they are types of deserts. People have always lived in the desert N stuff of stories and legends, such as Desert Gibson Desert Sturt Stony Desert environment and there are communities associated with always dry. the Navajo of the Mojave Desert in Kalahari Great Victoria Desert Patagonian Desert specific desert locations. Desert 2 Deserts cover 30 per cent of the the USA, the Mongols from the Gobi Earth’s land surface. 661°S Desert in Mongolia, and the Bedouin What are deserts? 2 SOUTHERN OCEAN Antarctic Circle 3 Typically, hot deserts are found from Saudi Arabia. In this unit, Deserts are environments that receive very low rainfall. Antarctica Deserts can be hot or cold, but they are always dry. They Key Hot dry desert Rainshadow desert Monsoon desert Cold Ocean in latitudes 30°N and 30°S. students will identify the location 0 2000 4000 km support sparse and specialised vegetation and limited Mid-latitude desert Coastal desert Polar desert currents 4 The six main types of deserts of deserts around the world and populations of animals and people. are: learn of the communities that have A desert environment can be classified as: 7.5 Deserts (excluding polar lands), their people and area • hot, dry deserts or trade • extremely arid—where there might be no precipitation survived in each location. 7.1 A Berber woman Activities for years, for example the Atacama Desert of Chile, of the Sahara Rank Name Location Communities Area wind deserts South America of people (× 1000 km2) Knowledge • mid-latitude or semi-arid • arid—where there is less than 250 millimetres of rain 1 Sahara North Africa Taureg, Berber, 9065 1 What is the definition of a desert? per year, for example the Sahara of northern Africa desert Nubian 2 How much of Earth’s land surface is covered by desert? • semi-arid—where there is between 250 and types of deserts • rainshadow deserts 2 Gobi Mongolia and Mongol 1295 3 Where are typical hot, dry deserts generally found? 500 millimetres of rain annually and usually in a There are six main types of deserts, as summarised in the • coastal deserts Vocabulary China 4 Name the six main types of deserts. distinct wet season, for example the Tanami Desert in table below. the Northern Territory, Australia. 3 Patagonia Argentina Mapuche 673 5 What is the largest desert in the world? Where is it located • monsoon deserts preview 7.3 Main types of desert environment and what communities of people live there? 4 Rub’ al-Khali Saudi Arabia Bedouin, 650 • polar deserts. Where are deserts Name Location Examples Qashquai Skills 5 The largest desert is the arid leeward located? Hot, dry desert or Close to or between Sahara, Simpson, 5 Kalahari Southern !Kung, San 582 6 Use an atlas and 7.3 to name 10 countries that contain Sahara, which is located trade wind desert 20º and 30ºN and Great Victoria, deserts. The world map in 7.4 shows the global distribution of Africa 20º and 30ºS Kalahari, Rub al-Khali in North Africa. Three Atacama Mojave deserts. Deserts are not restricted by latitude, longitude or 7 Refer to 7.4. Draw a column graph to show the area of the 6 Chihuahuan United States; Huichol 455 six largest deserts. communities of people live in height above sea level, but in general the typical hot, dry Mid-latitude or semi- Between 30º and 50º Sonoran, Gobi, Negev, Mexico global distribution rainshadow deserts are located between 20° and 30°N and between arid desert from the Equator Sinai, Patagonian, Application this desert: the Taureg, Berber 20° and 30°S due to global patterns of air circulation.
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