Physical Geography

views updated May 21 2018

Physical Geography

THE SARGASSO SEA

Sources

Borders. Europe is bordered by water on three sides. The western boundary is the Atlantic Ocean, the northern boundary is the Arctic Ocean, and the southern boundary includes the Mediterranean Sea and the Black Sea. These bodies of water provide clear boundaries but are themselves so distinct that Europeans living on the shores of one body of water have a radically different experience with the water than inhabitants living on a different body of water. The sheltered coasts and many natural harbors fostered sea-oriented, or maritime, economies that prospered during the late Renaissance and Reformation periods as naval developments turned the vast stretches of water into highways for trade and travel. The Ural Mountains, the Caspian Sea, and the Caucasus Mountains form an eastern frontier that is more ambiguous than the other borders.

Great European Plain. Between the low Ural Mountains and the relatively high Caucasus Mountains lies the eastern edge of the Great European Plain. This vast flat-land stretches from the Pyrenees Mountains that divide modern France and Spain and across Germany, Poland, and Russia before ending at the Ural Mountains. The Caspian Gate, a mountain pass south of the Urals and north of the landlocked Caspian Sea, allows one to pass from Amsterdam in the west straight through to the borders of Western China, with elevations that barely exceed sea level. Glaciers on the northwestern edge of the plain, in what is now the eastern border of modern Finland, have receded and left more varied geography with tens of thousands of small lakes, but other regions of the plain have relatively few lakes.

Rivers. The Great European Plain is drained by various rivers, such as the Volga, Dneiper, Vistula, Oder, Elbe, Seine, and Loire. These and other rivers of Europe provided access to the seas and better transportation opportunities for early-modern Europeans than overland routes. As a result, most major cities in Europe are located along waterways: London on the Thames; Paris on the Seine; Vienna and Budapest on the Danube; Warsaw on the Vistula; Copenhagen, Stockholm, and St. Petersburg on the Baltic Sea; Amsterdam on the North Sea; Lisbon on the Atlantic; and a shoreline full of cities on the Mediterranean. Furthermore, river valleys tend to be suitable for intensive agriculture, which is a prerequisite for urban development. Cities even dot the shores of rivers that were not navigable in the Renaissance and Reformation periods because river valleys also provided an opportunity to travel long distances with only slight variation in altitude. In fact, one can travel at water level from the Mediterranean Sea to the Atlantic Ocean over the French isthmus, a land bridge that connects two bodies of land. In the early Renaissance these travel opportunities made France the only area of Europe that clearly belonged to both the Atlantic world of Northern Europe and the Mediterranean world of Southern Europe.

Peninsulas and Isthmuses. France is part of a long isthmus that connects the Iberian Peninsula (Spain and Portugal) to the Asian continent. France also includes smaller peninsulas, such as Brittany and Normandy, which jut into the English Channel toward the British Isles. The European continent itself is a peninsula of smaller peninsulas, or landmasses that jut into water. These peninsulas are connected to the great Eurasian landmass by a wide isthmus known as the Great European Plain. The Iberian, Italian, Balkan, Scandinavian, and Danish peninsulas are the five most prominent peninsulas. Inhabitants of four of these peninsulas were forced to turn to the seas for trade because mountains hindered land travel: the Pyrennees isolated Spain and Portugal on the Iberian Peninsula, the Alps isolated the Italian peninsula, the Balkans isolated the Balkan peninsula, and the mountains of the Scandinavian peninsula limited travel across it. Island and peninsular inhabitants therefore turned to the seas at an unprecedented pace in the Renaissance and Reformation. The ability to cross the oceans dramatically changed Europe because remote outposts such as Portugal suddenly became the center of European shipping.

Islands. Advances in shipping were also significant for the many large inhabitable islands that are located in the Atlantic Ocean to the west of the continent. The largest of these islands, Iceland and the British Isles, are virtually small-scale continents. Access to these islands was greatly enhanced by Renaissance shipping technology, yet many Atlantic islands remained largely isolated. Danish islands in the Baltic Sea formed a bridge from the Danish to the Swedish peninsula and were important for Hanseatic trade in the Baltic. Mediterranean islands prospered in the late Middle Ages from Venetian and Genoese trade routes. Sardinia, Corsica, Sicily, Cyprus, Crete, and Rhodes, the largest of the Mediterranean islands, provided stopping points for sea routes and visual points for navigation. When these islands were integrated into shipping routes, their main port cities flourished, but the economic prosperity rarely spread to the interior of the islands. The interior of wealthy Sicily lacked the roads, bridges, and agricultural production found on the continent. Changes in shipping routes, due to technology or political factors, could quickly demolish the economic prosperity of port cities. Smaller islands also had a pattern of boom and bust as nonnative crops such as sugar cane were introduced. The shift from Mediterranean to Atlantic trade negatively influenced Mediterranean islands but proved to be a tremendous boon to Atlantic islands.

Three Geographical Regions. European geography can be broken into three general regions: the fold mountains, the highlands or uplands, and the lowlands. Each region can be further divided, such as dividing the highlands into the Central Uplands and the Northwestern Highlands, but the three general regions have distinct features that influence inhabitants. Higher elevations, be they uplands or fold mountains, border Europe on the northwest, the east, and the south. Nestled between these higher elevation areas are fertile plains, coastal lowlands, and river-valley basins.

Fold Mountains. The Alpine mountain system in Europe consists of high mountains and rugged plateaus that extend on a west-east axis from the Sierra Nevada and Pyrenees to the Caucasus Mountains. The Pyrenean Mountains, or Pyrenees, form a boundary between France and Spain on the western Mediterranean basin. The Baetic cordillera, or Sierra Nevada, is the westernmost alpine range situated in the southeast of Spain. The Balearic Islands are part of a submerged ridge of mountains that rises above the sea to form Cabrera, Formentera, Ibiza, Majorca, Minorca, and eleven other smaller islands. The Alpes Maritimes form an east-west line of mountains in southern France. To their north the Alps run from the French Riviera to Austria. Rugged peaks, such as the Matterhorn, and deep valleys are evidence of earlier glacial erosion that created this majestic band of mountains. Rugged peaks are also evident to the west of the Alps, in the Jura, which stretch from the cities of Basel and Geneva in Switzerland westward into eastern France. East of the Alps the Carpathians are a long range of rounded, forested mountains that consist of three distinct sections: the northern Carpathians in Czechoslovakia and Poland; the eastern Carpathians, which arc from the Ukraine to Romania; and the Transylvanian Alps, or southern Carpathians, which run from east to west across Romania. The Appennines run south of the Alps through the Italian peninsula. To their south the triangular island of Sicily is itself a mountain range famous for the volcanic Mount Etna, although the highest peak is Mount Madonie. Parallel to the Italian Appennines and to the east, across the Adriatic Sea, run the Dinaric Alps. A southern continuation of the Dinaric mountains is called the Hellenic mountains, or Greek mountains. The Cretan arc on the Island of Crete is the southern extent of the Alps. The Balkan highlands run west-east parallel to and just south of the Danube River through Bulgaria to the Black Sea. The Crimean peninsula on the northern side of the Black Sea has mountains on the south that fall to the Crimean steppes, or highlands, to the north and then fall further north into the Great European Plain. The easternmost Alpine region of Europe is the Caucasus Mountains that form the southeastern border of Europe. This rugged range can be divided into the greater Caucasus to the north and the lesser Caucasus to the south. The highest peaks are in the western edges of the greater Caucasus. The eastern border of Europe is formed by the Ural mountain range that consists of the heavily glaciated northern Urals and the wide central and southern Urals.

Interior Trade. The southern Alpine belt would appear to hamper European trade, but in fact the topography allows for trade within Europe. Wide river valleys are suitable for land transportation in the French Languedoc, between the Alps and the Pyrenees, the long Danube valley between the Alps and the Carpathians, and the valleys of the Morava and Vardar rivers that flow through the Balkan ranges. Glaciers carved deep valleys into the Alps and the Carpathians, the longest mountain ranges, which are connected by mountain passes for transportation. However, the Pyrenees to the southwest and the Caucasus to the southeast pose severe hindrances to trade except along the narrow seashores. Mountains thus pose serious boundaries for trade into and out of Europe on the southeast and southwest but only limited hindrances to trade within Europe.

THE SARGASSO SEA

During the initial voyage of Christopher Columbus to the New World in 1492, his ships encountered a strange expanse of water in the central North Atlantic west of the Azores. This large tract of comparatively still but clear water was oval in shape and filled with seaweed. Columbus took the presence of the weed as a sign that land was near, although his sailors had misplaced fears that their ships would become ensnared in the tangle of floating vegetation.

What Columbus did not know at the time was that he was still hundreds of miles from land. The area of water he encountered has been dubbed the Sargasso Sea by mariners and scientists. (Free-floating brown seaweed is from the genus Sargassum.) The Sargasso Sea covers approximately 2 million square miles (two-thirds the size of the contiguous United States) and because of clockwise-flowing currents it can be found in the area bordered by the parallels 20°N and 35°N and the meridians 30°W and 70°W. A shallow warm pool covers deeper, colder waters with depths ranging from 5,000 feet to 23,000 feet. Light winds, weak currents, low precipitation, and high evaporation all combine to create an aquatic desert almost totally devoid of plankton, the basic food source for most marine life, although the sea is home to certain species of crabs, shrimp, eels, and flying fish.

Source: John and Mildred Teal, The Sargasso Sea (Boston: Little, Brown, 1975).

Highlands. Running alongside the diverse mountains of Europe are the half-mountain plateaus, hills, and foothills that are quite distinct from the mountains. The Massifs, or Central Uplands, are highlands that border or lay between the southern Alpine mountain ranges and thus also follow a west-east axis: Spanish Meseta (Iberian Peninsula), Massif Central (France), Ardennes Plateau, Bavarian Plateau, Volga Heights, and Podolian Plateau (north of the Carpathians). These scattered uplands are grassy and suitable for fodder crops. As a result, they are areas which developed intensive animal husbandry. The Northwestern or Atlantic Highlands follow a southwest-northeast axis running from the Breton Peninsula in northwestern France northeast to Lapland: France, Ireland, Scotland, Iceland, Norway, Sweden, and Lapland. These highlands have thin soil and rugged topography that is suitable for sheep and cattle grazing. The craggy, hilly uplands in many areas are known for their isolation and ruggedness.

Lowlands and Plains. The coastal lowlands and river-valley plains consist of rolling plains that are suitable for intensive agricultural development: the Great European Plain, Po Basin, Paris Basin, Southern England and Eastern Ireland, Hungarian Plain, Wallachian Plain, and the Bohemian Plain. The Great European Plain is a vast flatland that stretches from western France to the Ural Mountains. The name plains suggests abundance, fertility, and good living, but in fact the Great European Plain was easily traversed and thus susceptible to outside invasions. This situation allowed Russia to move eastward and create an empire, but it also left Poland vulnerable to attacks from the east and the west. The cleared forests of the northern European plains are quite different from the much smaller Mediterranean plains. The Mediterranean plains frequently faced severe water and drainage problems. Communal efforts to alleviate these problems resulted in fertile farmland that was conducive to intensive agricultural production. All European plains shared the responsibility of providing agricultural resources for an urban world that existed quite distinctly from the rural plains.

Sources

Fernand Braudel, The Mediterranean and the Mediterranean World in the Age of Philip II, 2 volumes (New York: Harper & Row, 1972-1973).

Edwin Michael Bridges, World Geomorphology (Cambridge & New York: Cambridge University Press, 1990).

David L. Clawson and James S. Fisher, World Regional Geography, sixth edition (Upper Saddle River, N.J.: Prentice Hall, 1998).

Physical Geography

views updated Jun 11 2018

Physical geography

Physical geography is a scientific discipline that addresses the distribution of natural features and processes within a spatial, or geographical, reference frame. This subdiscipline of geography is an interdisciplinary amalgam of such diverse subjects as geology , ecology, environmental science, computer science, and aerospace engineering. When examined, the narrow definition of physical geography as the study and creation of physical maps expands into a broad array of topics from satellite remote sensing to computer-aided mapping known as geographic information systems (GIS ), to the study of surficial geological processes. The basic work of physical geology lies in determining how natural phenomena are spatially ordered, and in illuminating these geographic patterns using maps and images; the fundamental question behind physical geographic studies is why these patterns exist in nature.

The history of physical geography spans nearly four thousand years. Archeologists have discovered maps created by ancient Chinese, Phoenician, and Egyptian explorers, including a Babylonian map carved in a clay tablet dated at about 2300 b.c.Aristotle (384322 b.c.) suggested that the earth is a sphere based on his observations of lunar cycles. Eratosthenes (circa 276194 b.c.) accurately calculated the circumference of the earth using a geometric proof. Ptolemy (circaa.d.100170) developed a number of map projection schemes, as well as the coordinate system using latitude and longitude . Most of these early Greek and Roman geographical insights were forgotten during the Middle Ages (6001400), especially in Europe . In fact, the idea of a spherical Earth did not resurface until the Renaissance when European navigators, including Christopher Columbus, Ferdinand Magellan , and Sir Francis Drake, explored the oceans and the Americas. Increasingly detailed physical and cultural geographic studies accompanied the rapid population growth, European colonization, and exploration of the American frontier that took place from the late 1700s the early 1900s.

Physical geography underwent a quantitative revolution beginning in the 1950s, when geographic investigations became more scientifically rigorous. This revolution continues today with ever-improving geographical methods and tools like satellite-aided navigation using the Global Positioning System (GPS ), and images of the earth collected from space . Another change in the science of physical geography since the 1950s has been an increasing focus on the ways that humans affect their natural environment. Precise geographical information that documents or explains anthropogenic changes in the natural world is valuable to decision-makers across the ideological spectrum, from environmentalists, to government resource managers, to insurance actuaries.

See also History of exploration I (Ancient and classical); History of exploration II (Age of exploration); Mapping techniques; Projections