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Chapter 17 Physical Geography of North Africa, Southwest Asia and Central Asia 1. The Land The vast region of North Africa, Southwest Asia and Central Asia spans portions of Africa and Asia Early civilizations thrived here thousands of years ago in fertile river valleys Today, ancient rivers such as the Nile remain vital to the people of the region Landforms In NA, SWA and CA, dramatic landforms can be found It is a region dominated by deserts and mountains Tectonic activity responsible for shaping the landscape in many parts of NA, SWA and CA. Earthquakes The African, Arabian, Anatolian and Eurasian plates come together in NA, SWA and CA As the plates move they: build mountains shift landmasses cause earthquakes Tectonic activity built Atlas Mtns. of Morocco and Algeria, the Zagros of southern Iran and the Taurus of Turkey Earthquakes occur regularly in the region In 1999, Turkey experienced an earthquake measuring 7.4 on the Richter scale Mountains Physical Map on p. 412 Africa’s longest mountain range, the Atlas Mountains, extends across Morocco and Algeria In Southwest Asia, two mountain ranges, the Hejaz and Asir, stretch along the western coast of the Arabian Peninsula Precipitation received by the Asir region makes it the most agriculturally productive on the Ariabian Peninsula Turkey possesses the Pontic Mountains and the Taurus mountains, and in between the two sits the Anatolian Plateau (2000 to 5000 ft above sea level) Mountains Mount Ararat (almost 17000 ft), near Turkish/Iranian boder The Caucasus Mountains, located N of Mount Ararat between the Black Sea and Caspian Sea West of Tian Shan range, the Turan Lowlands, made up by irrigated farmland To the south are dune-covered kums, or deserts The Kara-Kum, or black sand desert, covers most of Turkmenistan The Kyzl Kum, or red sand desert, blankets half of Uzbekistan Coastal Plains, Seas and Peninsulas Regions agricultural base are the fertile plains along the Mediterranean Sea, the Caspian Sea and the Persian Gulf To the E, the Red Sea and the Gulf of Aden separate Arabian Peninsula from Africa The northwest, the Gulf of Suez and the Gulf of Aquaba flank the Sinai Peninsula Coastal Plains, Seas and Peninsulas To the N, the peninsula of Anatolia points west to the Aegean Sea Black and Mediterranean Seas lie at the peninsula’s north and south Three landlocked bodies of salt water E of the Mediterranean Sea: Smallest – Dead Sea, near mouth of Jordan River In CA, the Caspian Sea, largest inland body of water on Earth East of the Caspian Sea is the Aral Sea, used to be fourth largest inland sea before Soviet irrigation Water Systems For thousand of years, people have depended on the region’s rivers and fertile river valleys’ where early civilizations thrived Rivers are the lifeblood of this region, which on the whole is quite dry or arid Major Rivers: Cradles of Civilization Egypt’s Nile River, world’s longest river at 4,160 miles long The Nile, provided one of the world's earliest civilizations Today, more than 90 percent of Egypt’s population live on only 3 percent of Egypt's land, located along the Nile River The Aswan High Dam and others now control the river’s flow Major Rivers: Cradles of Civilization Early civilizations also thrived in the Tigris-Euphrates River Valley, fertile farming valley in SWA Known by ancient peoples as Mesopotamia, Greek word for ‘land between two rivers’ Today the Tigris and Euphrates help irrigate Turkey, Syria and Iraq The Euphrates is the longer river of the two (2,335 m), versus the Tigris (1,180m) Streambeds Many streams in the region flow only intermittently In the region’s deserts, runoff from infrequent rainstorms creates wadis, or streambeds that remain dry until a heavy rain Rainstorms often produce flash flooding During a flash flood, wadis fill with so much sediment they become mud flows, or moving masses of west soil, which are dangerous to humans and animals Natural Resources Some of NA, SWA and CA’s most abundant resources are important to the world economy Include petroleum and natural gas Oil and Natural Gas Over 60 percent of the world’s known oil reserves are beneath this region About 50 percent of known natural gas reserves are here as well Petroleum exports have enriched the region However, reliance on oil exports is risky, due to fluctuation in oil prices Minerals Turkmenistan, worlds’ largest deposits of sulfur largest deposits of sulfate, used in paperboard, glass and detergents Morocco – a leading producer in phosphate, chemical used in fertilizers Building Diverse Economies Some countries are diversifying to reduce reliance on oil and mineral exports United Arab Emirates is investing oil wealth in banking, information technology and tourism Libya is investing in infrastructure, agriculture and fisheries 2. Climate and Vegetation Large expanses of North Africa, Southwest Asia and Central Asia have an average annual rainfall of 10 inches or less As a result, much of the region arid, unfertile, desert Water and Climate Lack of water affects climate, natural vegetation, and human activities in these regions Water scarcity defines the region's climates Ancient cave paintings in North Africa, show us this part of Africa was once wet and green Desert Climate Scientific definition of desert: an area which averages 10 inches or less precipitation per year Deserts make up almost 50 percent of North Africa, Southwest Asia and Central Asia Sahara Desert – largest desert in the world, 3.5 million square miles, covers most of North Africa, expanded by recent droughts Desert weather patterns tend to be extreme, with relatively cold winters with freezing temperatures, and summers that are long and hot A traveler crossing any of the region's deserts would probably see only a few Ergs, but man Regs Ergs – sandy, dune covered area Regs - stony plains covered with rocky gravel (desert pavement) and hamada, a flat sandstone plateau Desert Climate Sand covers less than 10 percent of the Sahara. Mountains, barren rock and desert pavement cover the rest Rub’ al-Khali Desert – largest area of sand in the region, 250,000 square miles, covers almost the entire southern quarter of the Arabian Peninsula The Sahara and other deserts support some vegetation , such as cacti and shrubs. Small-scale farming is possible in an oasis, or place in the desert where underground water surfaces. Oases such as these are often the sites of villages, towns and cities in the Sahara Steppe Climate Steppe is the second largest climate region in the region Steppe borders the Sahara to the north and south Precipitation in this semi-arid climate region usually averages less than 14 inches per year Supports short grasses, providing pasture for sheep, goats and camels, as well as shrubs and some trees Pastoralism, the raising and grazing of livestock, is a way of life for people who live in a steppe climate Midlatititude Regions Countries within the region’s mid-latitudes benefit from rainfall in the Mediterranean highland, and humid subtropical climates Mediterranean climates have cool, rainy winters and hot, dry summers Exports and Tourists Morocco, Tunisia, Syria boost their economies by exporting citrus fruits, olives and grapes Some Mediterranean countries benefit from tourism Moroccan city of Agadir has 360 days of sunshine per year Higher area, like the Caucasus Mountains, are generally wetter and colder Highland climate varies with elevation and exposure to wind and sun Rainfall Coastal and highland areas near mountain ranges usually receive the most rainfall North African coast near the Atlas Mountains averages more than 30 inches of rain/year More than 60 inches of rain falls each year at the foot of the Elburz Mountains in northern Iran Batumi, in the Republic of Georgia, receives more than 100 inches of rain per year In areas where more than 14 inches of rain falls yearly, farmers can raise cereals, such as barley, oats and wheat, without irrigation
