Encyclopedia of Geography Terms, Themes, and Concepts

accounted for about 86 percent of global energy usage, a startling figure that high- lights the essential function such resource ...

fisheries, and other similar products are all biotic resources, as are hydrocarbon fuels, because they are derived from living m ...

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O Ocean Currents Earthis a water planet and the world ocean is always in large-scalemotion, slowly rearranging its waters over l ...

instance, the Gulf Stream leaves the vicinity of Florida with surface temperatures in excess of 27°C in the summer and the tempe ...

and especially pronounced in the latitudes of Peru and northern Chile. Its origins are at the latitudes of southern Chile (43°S) ...

oceans. At times, the Peru Current weakens causing rains in the Atacama Desert and catastrophic die-offs of ocean life; this phe ...

confined to continents and islands, and navigation was strictly on the surface until the 20th century, the ocean has been a real ...

Tropic of Cancer to Antarctica between 30°east longitude and 120°east longi- tude. The smallest ocean delineated is the Arctic a ...

deglaciation heralding the end of the last glacial episode 18,000 years ago, the sea level has risen 120 meters and the ocean ha ...

convection against the force of gravity. Interestingly, the troposphere—the lowest portion of Earth’s fluid atmosphere—is comple ...

characterized bypopulationgrowth and a stablecultural identity. Ratzel’s great admirer, the Swedish scholar Rudolf Kjellen, carr ...

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P Particularism A broadly applied term with several meanings in the social sciences and human- ities. Particularism in geography ...

the culturallandscapeand appeared later in the idea ofsequent occupance. Eventually, Sauer’s views led to the emergence of the f ...

centuries. In Central Asia, for example, the Kazakhs and Kyrgyz were nomadic pas- toralists for centuries, but were forced onto ...

Increasing world knowledge and science led Alfred Wegener (the son-in-law of the climate classifier Vladimir Ko ̈ppen) to publis ...

(N-S) of the planet at the time magma cools into volcanic rock. Earth scientists had previously realized that the polarity of Ea ...

for instance, has opened up in the last quarter of a billion years at an average rate of the growth of a human finger- nail. Thi ...

volcanic arc of the Mariana Islands of the western Pacific. (4) Other convergences are continental-continental collisions. In th ...