North America is the northern continent of the Western Hemisphere. From 1492 to 1504, Columbus led a Spanish fleet to explore the West Indies 4 times, and 4 voyages to the coastal areas of the Bahamas, Antilles and the Central American Isthmus. In 1497, Cabot and his son arrived in Newfoundland and entered along the St. Lawrence Estuary. About 40 years later, Cartier led the French army up the St. Lawrence River to reach Montreal. After the Europeans "discovered" the New World, they successively occupied and colonized the Indians, cruelly plundered and wanton slaughter of the Indians, and drove them from the land they lived in to the arid areas of the west.
In the mid-16th century, the Spaniards first established the colony of St. Augustine in the main part of the continent north of the border between the United States and Mexico. At the beginning of the 17th century, the French established their first settlement in Nova Scotia on the east coast of Canada, and subsequently established a colony of Quebec. Using this as a base, they went up the St. Lawrence River, crossed the Great Lakes, and descended along the Mississippi River to the south. The Gulf Coast region.
The British established the first permanent colony in Virginia at the beginning of the 17th century. Since then, the Netherlands, Finland and Sweden have colonized the Atlantic coast. By the early 18th century, the colonial power of the North American continent was basically one-third of the world. Britain occupied the narrow strip of Atlantic coast from Nova Scotia to Florida; France occupied the vast and fertile central plains from the St. Lawrence River, the Great Lakes to the Mississippi River; Spain occupied Florida, Texas, New Mexico, and the vast expanse of the Pacific coast west to the Pacific. The Far West.
Not long after the British colonial power took root in the eastern part of the mainland, British immigrants and their descendants staged an armed uprising, and separated from Britain in 1776 to establish the United States of America. At the same time, some pro-British imperial anti-independence activists moved northward to settle in the Canadian provinces of Ontario and Quebec. This is the embryonic form of the two major powers of the North American continent, the United States and Canada.
In the middle of the 19th century, the United States expanded to the Pacific coast. Canada became a dominion in 1867, and its territory advanced to the Pacific coast in the 1870s. After the completion of the trans-continental railway line, it set off an upsurge in the development of the central and western regions. So far, the main part of the North American continent has basically been controlled by British colonial forces. Only two small islands, St. Pierre and Miquelon, south of Newfoundland, remain in France. After expanding its territory to the Gulf of Mexico, the United States began to expand to the Central American Isthmus and the West Indies. It occupied Puerto Rico, controlled the Panama Canal Zone, purchased three islands in the Virgin Islands, and took over several more during World War II. British colony. As a result, the influence of the United States in the southern part of the North American continent, the Central American Isthmus, and the West Indies, which were monopolized by the early Latin-speaking suzerainty, has grown day by day.
Geographical overview
Topography
The plains below 200 meters above sea level account for about 20%, and the plains and hills above 200-500 meters above sea level account for about 22% , Plateaus and mountains above 500 meters above sea level account for about 58%, with an average elevation of 700 meters across the continent. The basic feature of the continental topography is that the north-south mountain ranges are distributed on the east and west sides parallel to the coast, and the large plains are distributed in the middle. The terrain is clearly divided into three zones.
Eastern mountains and plateaus: the Labrador Plateau to the north of the St. Lawrence River, and the Appalachian Mountains to the south. The terrain is high in the south and low in the north. The elevation is generally 300-500 meters. On the east side of the Appalachian Mountains, there is a narrow coastal plain along the Atlantic Ocean, and the west side gradually descends to meet the central plain.
Central Plain: Located between the Labrador Plateau, the Appalachian Mountains and the Rocky Mountains, it extends from the Hudson Bay in the north to the Gulf of Mexico in the south and runs through the middle of the mainland. There are many lakes and rapids in the northern half of the plain, and the Mississippi River plain in the southern half. The western part of the plain is the world-famous Great Plain.
Western mountains and plateaus: It belongs to the northern section of the Cordillera Mountain System, extending from Alaska to the south of Mexico, mainly including three parallel mountains, and the eastern belt is the Rocky Mountains above 2000-3000 meters above sea level. , Extending 5,000 kilometers from north to south, is an important dividing line in the climate of North America; the western belt extends from the coastal mountains of the United States in the south and enters the sea north to form the coastal islands of western Canada. The altitude is generally 500-1000 meters; the middle belt includes the northern ones. The Alaska Mountains, the Coastal Mountains of Canada, the Sierra Nevada Mountains and the Cascade Range in the United States. Mount McKinley in Alaska is 6,193 meters above sea level and is the highest peak in North America.
There are plateaus and basins between the eastern and central belts. The bottom of the large basin is 800-1300 meters above sea level. The dead valley in the southern part of the basin is 86 meters below sea level, which is the lowest point of land in the western hemisphere. North America has a high average elevation and large undulations. The topography is divided into three north-south series: the west is a tall mountain system, the middle is a vast plain, and the east is a low plateau.
Volcanoes and earthquakes
The western coastal area of North America is part of the Pacific Coast Volcanic Belt. There are more than 90 active volcanoes in North America, including 28 in the Aleutian Islands, 20 in Alaska, and more than 40 in Central America. Western North America is also a zone where earthquakes are frequent and strong in the world.
Water system
The outflow area of North America accounts for about 88% of the continent's area, of which the Atlantic basin accounts for about 48% of the continent, and the Pacific basin accounts for about 20%. %. Except for the St. Lawrence River, all major rivers originated in the Rocky Mountains. Rivers east of the Rocky Mountains flow into the Atlantic and Arctic Oceans, and rivers to the west flow into the Pacific Ocean. The internal flow area (including the no-flow area) accounts for about 12% of the continent's area, mainly distributed in the western United States and Greenland. The Mississippi River is the largest river in North America and the fourth largest river in the world in terms of length. Followed by Mackenzie River, Yukon River, St. Lawrence River and Rio Grande River. Other more important rivers are: Colorado River, Ohio River, Columbia River, etc.
There are many waterfalls on the rivers of North America. The largest waterfall is Yosemite Falls in Yosemite National Park in the western United States, with a drop of 739 meters. Niagara Falls has a drop of 54 meters and a width of 1160 meters. North America is a continent with many lakes. The total area of freshwater lakes is about 400,000 square kilometers, ranking first among all continents. The lakes are mainly distributed in the northern half of the continent. The five great lakes in the Central Highlands: Lake Superior, Lake Huron, Lake Michigan, Lake Erie, Lake Ontario, with a total area of 245,273 square kilometers, are the largest freshwater lakes in the world and are known as the "Mediterranean North America". Among them, Lake Superior has the largest area and the largest freshwater lake in the world.
Climate
North America West America 2(15 photos)
North America straddles tropical, temperate, and frigid zones, and the climate is complex and diverse. It is dominated by temperate continental climate and sub-frigid coniferous forest climate. The northern part is in the Arctic Circle and is the world of ice and snow. The southern Caribbean Sea is benefited by the warm equatorial current, but it is hit by tropical hurricanes. The vast area in the central part of the mainland is located in the northern temperate zone, which is suitable for crop growth and human survival.Because all the mountains are north-south or nearly north-south, the humid air from the Pacific Ocean only reaches the western coastal areas; the cold air from the Arctic Ocean can drive southward through the central plain; the humid air from the tropical Atlantic also It can go deep into the north through the Central Plains, so the climate in North America is very unstable. Winter is sometimes cold and sometimes thawed. In the subtropical areas along the Gulf of Mexico, severe cold and snow will also occur in winter.
The coldest month (January) in North America where the average temperature is below 0°C accounts for about 3/4 of the continent's area. Collectively) and most areas of Greenland are below -32°C, and the central part of Greenland is as low as -50°C, becoming the cold polar region of the Western Hemisphere. In summer, the whole continent generally increases in temperature. The average temperature in the hottest month (July, mostly on the coast) is 0~3℃ in central Greenland, making it the coolest summer in the northern hemisphere; the rest of the vast areas are between 0-32℃ Among them, areas above 20°C account for more than half of the continent's area, and areas above 30°C are relatively small. Death Valley in the southwestern United States has an extreme maximum temperature of 56.7°C, making it the hottest region in the continent. The eastern part of North America has more precipitation.
The annual precipitation in the southeastern part of Canada and Greenland, the eastern part of the United States, the Pacific coast of Canada and Alaska is about 500-300 mm; the Pacific coast of Canada and Alaska is more than 2000 mm, which is North America The areas with the most precipitation; the annual precipitation of the Florida Peninsula is 1000-1500 mm, the eastern foothills of the Rocky Mountains and the Great Plains, and the Yukon Plateau have an annual precipitation of 250-100 mm; the Caribbean has a tropical rain forest climate with high temperature and rain throughout the year. The areas with the least amount of precipitation are the southwestern part of the Great Basin of the United States, the lower part of the Colorado River, and the northern part of the Arctic Islands and Greenland, with an average annual rainfall of less than 100 mm. In May each year, southeastern North America is often hit by hurricanes, often causing serious disasters. Winter in central and northern North America often blows cold and strong storms and land tornadoes. After the west wind crossed the Rocky Mountains, the Chinook wind formed at the eastern foot of the mountain.
Coastline
The continental coastline is about 60,000 kilometers long. The northern, northern and eastern coasts of the west are relatively tortuous, with many islands and fjords; the southern half of the coast is relatively straight.
Peninsula and islands
The total area of the peninsula is approximately 2.1 million square kilometers. The total area of the island is about 4 million square kilometers, ranking first among all continents. Greenland is the world's largest island, 80% covered by glaciers, and is a Danish colony.
Geographic Center
In a 2015 paper published in the academic journal "The Professional Geographer" (The Professional Geographer), Rogerson proposed a new method of defining the center of a spatial entity. This method improves on past techniques, he said, taking the curvature of the earth into account and using definitions (a reasonable mathematical method) to identify the geographic center. Rogerson uses a technique called equidistant azimuth projection by geographers. When a circular three-dimensional part of the earth is projected onto a two-dimensional plane, the technique makes the area on the map equal to the corresponding actual ground area.
At the end of 2016, he used this method to find the center of North America. The result was discovered by accident: According to his calculations, the center of the North American continent is in a place called Center (Center: the English name center), which is a small town of 570 people in North Dakota.
Regional division
Divided into nine regions: Eastern Region, Central Region, Western Region, Alaska, Canadian Arctic Islands, Greenland, Mexico, Central America and West Indies. It is bounded by the Bering Strait and Asia, and the Panama Canal and South America.
Eastern region
It is bordered by the Atlantic Ocean in the east, the coast is tortuous, and there are many harbors. Most of the ports in North America are concentrated in this area. The Labrador Plateau is north of the St. Lawrence Valley. At an altitude of 300-600 meters, there are many glacial lakes, known as the lake plateau; the Appalachian Mountains to the south, generally 1000-1500 meters above sea level, the Appalachian Plateau on the west side of the mountain, the mountains and the Atlantic Ocean are narrow The piedmont plateaus and coastal plains. Numerous short and turbulent rivers flow through the junction of hard and soft rock formations in the foothills, forming waterfalls, so the line from New York to the southwest to Columbus is known as the "waterfall line". This area is the earliest industrial and agricultural development area in North America, and it is also an important industrial, commercial and financial center.
Central Region
Located in the Labrador Plateau between the Appalachian Mountains and the Rocky Mountains, from the upper reaches of the Churchill River in the north to the Gulf of Mexico in the south, it is about 3000 in length An area about 2,000 kilometers wide. It is the most concentrated production area of wheat, corn, soybean, and cotton in North America and one of the most developed areas of meat animal husbandry.
Western Region
Composed of tall mountains and plateaus, it belongs to the northern section of the Cordillera Mountain System in the Americas. The Rocky Mountains are the backbone of the terrain of this region. There are many volcanoes, hot springs and frequent earthquakes. The inland has a dry climate and is dominated by animal husbandry. The horticulture industry for planting subtropical fruits in the Pacific coast is very developed. The mining industry in this area takes an important position, and the manufacturing industry is mainly aircraft and shipbuilding.
Alaska
Alaska is located in northwestern North America. In the continental part, the mountains are divided into north and south, and the central part is the Yukon Plateau. The Pacific coast is full of volcanoes and earthquakes are frequent. The main minerals include petroleum, gold, tin, copper, and coal. The economy is dominated by mining, fishery and fur industries. The Aleutian Islands are a group of volcanic islands in southwest Alaska, where earthquakes are frequent. The domestication and fishery of furry beasts.
Canadian Arctic Archipelago
is the collective name for the many islands north of the North American continent and west of Greenland. The area is about 1.6 million square kilometers. The population is sparse and the main residents are Inuit. There are many straits between the islands. Among them, the Hudson Strait between Baffin Island and the Labrador Peninsula is the main maritime traffic route between Hudson Bay and the Atlantic Ocean. The islands are exposed to hard rocks, mostly mountainous areas with an altitude of more than 500-1000 meters, lakes formed by long-term glaciers, multi-glacial terrains and glaciers. The coastal plains are narrow and the coasts are twisty and fjord. The climate is severely cold, with an average annual rainfall of less than 300 mm. Residents make a living by fishing and catching sea animals.
Mexico
Located in the southern part of North America, it is the origin of cultivated plants such as sisal and guayule.
Central America
is the collective name of Central Asia and America, referring to the central part of the American continent south of Mexico and north of Colombia. It borders the Caribbean Sea on the east and the Pacific Ocean on the west. It is a bridge connecting South and North America, including Guatemala, Honduras, Belize, El Salvador, Nicaragua, Costa Rica and Panama. The area is about 520,000 square kilometers and the population is about 29.84 million. The whole area is dominated by plateaus and mountains. The mountain is close to the Pacific coast and belongs to the middle section of the Cordillera Mountain System in America. The highest point is more than 4000 meters above sea level. There are many volcanoes, there are more than 40 active volcanoes, and earthquakes are frequent (see the text description of the map of China and the United States for details). Central America is the origin of sweet potatoes.
West Indies
It is located between the Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico. At the end of the 15th century, Italian navigator Columbus came here, mistakenly thinking that it was an island near India because it was located in the western hemisphere west of India, called the West Indies, and it has been in use all the time. Including the Bahamas, Cuba, Jamaica, Haiti, Dominican Republic, Antigua and Barbuda, Dominica, Saint Lucia, Saint Vincent and the Grenadines, Barbados, Grenada, Trinidad and Tobago, Saint Lucia Kitts and Nevis, etc., in addition to more than ten territories of the United States, Britain, France and the Netherlands. The area is about 240,000 square kilometers.
These islands are divided into three major groups: 1. The Bahamas, consisting of 14 larger islands, 700 small islands and reefs, and 2,400 atolls. Black people live mainly on the island. The highest islands are less than 60 meters above sea level. Tropical rain forest climate. 2. The Great Antilles, including Cuba, Haiti, Jamaica, Puerto Rico and its affiliated islands. Half with