A map of plant hardiness regions, as in Figure 1. Other formal regions might include religious or political affiliation, agricultural crop zones, or ethnicity. Formal regions might also be established by governmental organizations, such as the case with state or provincial boundaries.
Functional regions , unlike formal regions, are not homogenous in the sense that they do not share a single cultural or physical characteristic. Rather, functional regions are united by a particular function, often economic.
Functional regions are sometimes called nodal regions and have a nodal arrangement, with a core and surrounding nodes. A metropolitan area, for example, often includes a central city and its surrounding suburbs.
Los Angeles, for example, is the second-most populous city in the United States. However, the region of Los Angeles extends far beyond its official city limits as show in Figure 1. In fact, over , workers commute into Los Angeles County from the surrounding region every day.
Los Angeles, as with all metropolitan areas, functions economically as a single region and is thus considered a functional region. Other examples of functional regions include church parishes, radio station listening areas, and newspaper subscription areas.
Some people might include all of the states that formed the Confederacy during the Civil War. Others might exclude Missouri or Oklahoma. Vernacular regions exist at a variety of scales. Vernacular regions are real in the sense that our perceptions are real, but their boundaries are not uniformly agreed upon. As geographers, we can divide the world into a number of different regions based upon formal criteria and functional interaction. However, there is a matter of perception, as well. We might divide the world based on landmasses, since landmasses often share physical and cultural characteristics.
Sometimes water connects people more than land, though. In the case of Europe, for example, the Mediterranean Sea historically provided economic and cultural links to the surrounding countries though we consider them to be three separate continents. Do you have fewer regions united by only a couple characteristics, or more regions that share a great deal in common?
These regions are largely vernacular, however. Why is Russia its own region? These transition zones are marked by gradual spatial change. Moscow, Russia, for example, is quite similar to other areas of Eastern Europe, though they are considered two different regions on the map.
Even within regions, country borders often mark spaces of gradual transition rather than a stark delineation between two completely different spaces. The border between Peru and Ecuador, for example, is quite relaxed as international borders go and residents of the countries can move freely across the boundary to the towns on either side see Figure 1. Geography has two primary branches, physical and human geography, but numerous sub-disciplines, many of which include both physical and human elements.
A geographer might be a human geographer who specializes in culture who further specializes in religion. That same geographer might also conduct side research on environmental issues. And she might, in her spare time, investigate geographies of fictional landscapes. One benefit of geography is that its breadth offers a wide array of phenomena to explore. Everything happens somewhere, and thus everything is geographical.
This list is not inclusive, however. Some geographers study geodesy, the scientific measurement and representation of Earth. Others study pedology, the exploration of soils.
What unites physical geographers is an emphasis on the scientific study of the physical features of Earth in all of its many forms. Human geography, too, consists of a number of sub-disciplines that often overlap and interact. The main sub-disciplines of human geography include: cultural geography the study of the spatial dimension of culture , economic geography the study of the distribution and spatial organization of economic systems , medical geography the study of the spatial distribution of health and medicine , political geography the study of the spatial dimension of political processes , population geography also known as demography, the study of the characteristics of human populations , and urban geography the study of urban systems and landscapes.
Human geographers essentially explore how humans interact with and affect the earth. Political geography provides the foundation for investigating what many people understand as geography: countries and governmental structures.
The question is not as easy to answer as it might seem. What if a state declares itself independent, but is not recognized by the entirety of the international community?
What if a state collaborates so closely with its neighbor that it gives up some of its sovereignty? What happens if a state is taken over by another state?
As of , there are states that could be considered sovereign, though some are disputed and are only recognized by one other country. Only states are members of the United Nations.
In addition to questions of sovereignty, political geographers investigate the various forms of government found around the world see Figure 1. States govern themselves in a variety of ways, but the two main types of government are unitary and federal. In a unitary state , the central government has the most power. Local or regional governments might have some decision-making power, but only at the command of the central government.
Most of the states of the world have unitary systems. A federal state , on the other hand, has numerous regional governments or self-governing states in addition to a national government. Several large states like the United States, Russia, and Brazil are federations. Economic geographers explore the spatial distribution of economic activities. Why are certain states wealthier than others? Why are there regional differences related to economic development within a country?
All countries have some sort of economic system but have different resources, styles of development, and government regulations. So how can we compare countries in terms of economic development? Do not confuse the International Date Line with the prime meridian 0 longitude. The actual International Date Line does not follow the degree meridian exactly.
A number of alterations have been made to the International Date Line to accommodate political agreements to include an island or country on one side of the line or another.
The earth is tilted on its axis Places receiving more direct sunlight experience a warmer climate. The Tropic of Cancer is the parallel at Remember that the earth is tilted The Tropic of Capricorn is the parallel at The tropics Cancer and Capricorn are the two imaginary lines directly above which the sun shines on the two solstices , which occur on or near June 20 or 21 summer solstice in the Northern Hemisphere and December 21 or 22 winter solstice in the Northern Hemisphere.
The sun is directly above the Tropic of Cancer at noon on June 20 or 21, marking the beginning of summer in the Northern Hemisphere and the beginning of winter in the Southern Hemisphere.
The sun is directly above the Tropic of Capricorn at noon on December 21 or 22, marking the beginning of winter in the Northern Hemisphere and the beginning of summer in the Southern Hemisphere. Solstices are the extreme ends of the seasons, when the line of direct sunlight is either the farthest north or the farthest south that it ever goes. The region between the Tropics of Cancer and Capricorn is known as the tropics. This area does not experience dramatic seasonal changes because the amount of direct sunlight received does not vary widely.
The higher latitudes north of the Tropic of Cancer and south of the Tropic of Capricorn experience significant seasonal variation in climate. This sign was placed in this desert location by the Budapest-Bamako rally participants. The non-English portion is in Hungarian because of the European participants in the race. Wikimedia Commons — public domain.
The Arctic Circle is a line of latitude at During winter, the North Pole is away from the sun and does not receive much sunlight. At times, it is dark for most of the twenty-four-hour day. The Antarctic Circle is the corresponding line of latitude at When it is winter in the north, it is summer in the south.
The Arctic and Antarctic Circles mark the extremities southern and northern, respectively of the polar day twenty-four-hour sunlit day and the polar night twenty-four-hour sunless night. North of the Arctic Circle, the sun is above the horizon for twenty-four continuous hours at least once per year and below the horizon for twenty-four continuous hours at least once per year.
Equinoxes , when the line of direct sunlight hits the equator and days and nights are of equal length, occur in the spring and fall on or around March 20 or 21 and September 22 or Time Zones. This is the same time under which many military operations, international radio broadcasts, and air traffic control systems operate worldwide.
UTC is set in zero- to twenty-four-hour time periods, as opposed to two twelve-hour time periods a. The designations of a. For example, all air flights use the twenty-four-hour time system so the pilots can coordinate flights across time zones and around the world. Time zones are established roughly every 15 degrees longitude so that local times correspond to similar hours of day and night.
With this system, the sun is generally overhead at noon in every time zone that follows the degree-wide system. The continental United States has four main time zones see Table 1.
Table 1. Local time zones are either plus or minus determined by the distance from the prime meridian. In this diagram, 75 W is the central meridian for the eastern standard time zone in the United States.
For example, if it is noon in London, then it is 7 a. Since there are twenty-four hours in a day, there are twenty-four time zones on Earth.
Each time zone is 15 degrees wide. A problem with the degree time zones is that the zones do not necessarily follow state, regional, or local boundaries. The result is that time zones are seldom exactly 15 degrees wide and usually have varied boundary lines.
In the United States, the boundaries between the different time zones are inconsistent with the lines of longitude; in some cases, time zones zigzag to follow state lines or to keep cities within a single time zone.
Other countries address the problem differently. China, for example, is as large in land area as the United States yet operates on only one time zone for the entire country. A region is a basic unit of study in geography—a unit of space characterized by a feature such as a common government, language, political situation, or landform.
A region can be a formal country governed by political boundaries, such as France or Canada; a region can be defined by a landform, such as the drainage basin of all the water that flows into the Mississippi River; and a region can even be defined by the area served by a shopping mall. Cultural regions can be defined by similarities in human activities, traditions, or cultural attributes. Geographers use the regional unit to map features of particular interest, and data can be compared between regions to help understand trends, identify patterns, or assist in explaining a particular phenomenon.
Regions are traditionally defined by internal characteristics that provide a sense of place. Their boundaries vary with the type of region, whether it is formal, functional, or vernacular; each type has its own meaning and defined purpose. A formal region has a governmental, administrative, or political boundary and can have political as well as geographic boundaries that are not open to dispute or debate.
Formal boundaries can separate states, provinces, or countries from one another. Physical regions can be included within formal boundaries, such as the Rocky Mountains or New England. Please subscribe or login to access full text content. If you have purchased a print title that contains an access token, please see the token for information about how to register your code. For questions on access or troubleshooting, please check our FAQs , and if you can''t find the answer there, please contact us.
All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single entry from a reference work in OR for personal use for details see Privacy Policy and Legal Notice. Oxford Reference. Publications Pages Publications Pages. Language , government , or religion can define a region, as can forest s, wildlife , or climate. Regions, large or small, are the basic units of geography. The Middle East is considered a political, environmental, and religious region that includes parts of Africa, Asia, and Europe.
The region is in a hot, dry climate. Although the styles of government are varied democracy in Israel and Syria, monarchy in Saudi Arabia , almost all of them have strong ties to religion. The region is where three of the worlds major religions were founded: Christianity , Judaism , and Islam. This region is characterize d by warm temperature s, heavy rainfall , a large diversity of plant and animal species, and little human impact on the environment.
Geographers also use regions to study prehistoric environments that no longer exist. Due to plate tectonics , or the movement of the Earths crust , geographic regions are constantly being created and destroyed over time.
Paleogeography is the study of these ancient environments. One paleogeographic region is Pangaea , the supercontinent that existed millions of years ago, during the Paleozoic and Mesozoic eras. The continents we know today split apart from the supercontinent of Pangaea. West : All states west of the Mississippi River.
Also called the Age of Dinosaurs. Regions are the basic units of geography. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
Caryl-Sue, National Geographic Society. Dunn, Margery G. For information on user permissions, please read our Terms of Service.
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