Western Hemisphere

Western Hemisphere. The Western Hemisphere is a geographical term for the half of Earth that lies west of the Prime Meridian and east of the 180th meridian. It contains the continents of North America and South America in their entirety, along with surrounding islands and waters. This region encompasses a vast array of nations, from Canada and the United States to Brazil and Argentina, and is characterized by its significant cultural diversity and complex history of indigenous civilizations, European colonization, and modern geopolitical dynamics.

Definition and boundaries

The most common definition uses the Prime Meridian at 0° longitude, which passes through the Royal Observatory, Greenwich, and the antimeridian at 180° longitude as the dividing lines. This places the continents of North America and South America, as well as the Caribbean islands, entirely within this region. However, some alternative definitions, such as those used by the National Geographic Society, employ the 20°W and 160°E meridians to keep continents and related islands grouped together, thereby including parts of West Africa and Europe like Iceland and excluding the easternmost tip of Siberia. The International Date Line generally follows the 180th meridian, further cementing its role as a practical boundary. The Western Hemisphere is also one of two hemispheres created by the Greenwich Meridian, the other being the Eastern Hemisphere.

Geography and climate

The region is dominated by the American landmass, stretching from the Arctic Ocean in the north to the Drake Passage near Antarctica in the south. Major mountain ranges include the Rocky Mountains in North America and the Andes in South America, the latter being the world's longest continental mountain range. The Amazon rainforest, primarily within Brazil, represents the largest tropical rainforest on Earth, while other significant biomes include the Great Plains of the United States and the Patagonian Desert in Argentina. Climate zones range from the tundra of Alaska and Nunavut to the tropical climates of the Caribbean and Central America, influenced by systems like the Gulf Stream and the Humboldt Current. The Pacific Ocean borders the west, the Atlantic Ocean the east, and the region contains inland seas like the Great Lakes and the Gulf of Mexico.

Demographics and culture

With an estimated population of one billion, the region is linguistically and ethnically diverse. Dominant languages include Spanish, Portuguese, English, French, and Dutch, reflecting its colonial history under powers like Spain, Portugal, Great Britain, and France. Indigenous peoples, such as the Quechua, Nahuatl, and Mapuche, maintain vibrant cultures alongside communities of African, European, and Asian descent. Major cultural hubs include Mexico City, New York City, São Paulo, and Buenos Aires. The region is the birthplace of diverse musical forms like jazz, samba, reggae, and mariachi, and is home to global religious movements and a wide array of UNESCO World Heritage Sites, from Machu Picchu to The Statue of Liberty.

History

Human habitation began with migrations across the Bering land bridge, leading to advanced civilizations like the Maya, Aztec, and Inca. The Age of Discovery, marked by the voyages of Christopher Columbus in 1492 and Ferdinand Magellan's expedition, initiated widespread Spanish and Portuguese colonization. This period saw the Columbian Exchange, the Atlantic slave trade, and devastating conflicts such as the Spanish conquest of the Aztec Empire. The American Revolution and Haitian Revolution sparked waves of independence, with leaders like Simón Bolívar and José de San Martín liberating much of South America. The 20th century was defined by the World Wars, the Cold War—including events like the Cuban Missile Crisis—and the rise of influential figures from Franklin D. Roosevelt to Fidel Castro.

Geopolitical and economic significance

The region is a major center of global economic and political power, anchored by the United States and including other significant economies like Canada, Brazil, and Mexico. Key multilateral organizations include the Organization of American States (OAS), the North American Free Trade Agreement (NAFTA, now USMCA), and Mercosur. It holds vast natural resources, from the Athabasca oil sands to Chilean copper and Brazilian agricultural output. Strategic waterways like the Panama Canal and the Strait of Magellan are critical for global trade. Contemporary challenges and collaborations often focus on issues such as narcotics trafficking, migration, environmental agreements, and diplomatic forums like the Summit of the Americas.

Category:Western Hemisphere Category:Hemispheres of Earth