RAS MAINS WORLD GEOGRAPHY : General Studies Paper-II- RAS/RTS Mains Examination : RPSC RAS Mains General Studies Paper-II Unit-3 Part -A World Geography
Unit III- Earth Science (Geography & Geology)
Part A- World
• Broad Physical Feature: Mountains, Plateaus, Plains, Lakes and Glaciers
• Earthquakes and Volcanoes: Types, distribution and their impact
• Earth and its Geological time scale
• Current Geopolitical Problems – RAS MAINS WORLD GEOGRAPHY
The discipline of geography bridges the social sciences with the physical sciences and can provide a framework for understanding our world. By studying geography, we can begin to understand the relationships and common factors that tie our human community together. The world is undergoing globalization on a massive scale as a result of the rapid transfer of information and technology and the growth of modes of transportation and communication. The more we understand our world, the better prepared we will be to address the issues that confront our future. There are many approaches to studying world geography. Here we take a regional approach and focus on themes that illustrate the globalization process, which in turn assists us in better understanding our global community and its current affairs.
Geography helps us make sense of the world through four historical traditions:
- Spatial analysis of natural and human cultures
- Earth science
- Area studies
- Human-landscape interactions
Spatial analysis includes many of the concepts tied to geographic information science (GIS): the analysis of the interactions and distribution of many types of information using computer databases. The GIS data are entered into computer programs that convert location indicators to points or features on a map. Earth science includes the study of landforms, climates, and the distribution of plants and animals. Area or regional studies focuses on a particular region to understand the dynamics of a specific interaction between human activity and the environment. Researchers studying human-landscape interaction examine the impact of humans on their landscape and find out how different cultures have used and changed their environments. Geography provides the tools to integrate knowledge from many disciplines into a usable form by providing a sense of place to natural or human events. You will find that geography often explains why or how something occurs in a specific location. World geography utilizes the spatial approach to help understand the components of our global community.
Geography is the spatial study of the earth’s surface (from the Greek geo, which means “Earth,” and graphein, which means “to write”). Geographers study the earth’s physical characteristics, its inhabitants and cultures, phenomena such as climate, and the earth’s place within the universe. Geography examines the spatial relationships between all physical and cultural phenomena in the world. Geographers also look at how the earth, its climate, and its landscapes are changing due to cultural intervention.
The first known use of the word geography was by Eratosthenes of Cyrene (modern-day Libya in North Africa), an early Greek scholar who lived between 276 and 194 BCE. He devised one of the first systems of longitude and latitude and calculated the earth’s circumference. Additionally, he created one of the first maps of the world based on the available knowledge of the time. Around the same time, many ancient cultures in China, southern Asia, Polynesia, and the Arabian Peninsula also developed maps and navigation systems used in geography and cartography.
The discipline of geography can be broken down into two main areas of focus: physical geography and human geography. These two main areas are similar in that they both use a spatial perspective, and they both include the study of place and the comparison of one place with another.
Physical geography is the spatial study of natural phenomena that make up the environment, such as rivers, mountains, landforms, weather, climate, soils, plants, and any other physical aspects of the earth’s surface. Physical geography focuses on geography as a form of earth science. It tends to emphasize the main physical parts of the earth—the lithosphere (surface layer), the atmosphere (air), the hydrosphere (water), and the biosphere (living organisms)—and the relationships between these parts.
The major forms of study within physical geography include the following:
- Geomorphology (the study of the earth’s surface features)
- Glaciology (the study of glaciers)
- Coastal geography (the study of the coastal regions)
- Climatology (the study of climates and climate change)
- Biogeography (the study of the geographic patterns of species distribution)
Some physical geographers study the earth’s place in the solar system. Others are environmental geographers, part of an emerging field that studies the spatial aspects and cultural perceptions of the natural environment. Environmental geography requires an understanding of both physical and human geography, as well as an understanding of how humans conceptualize their environment and the physical landscape.
Physical landscape is the term used to describe the natural terrain at any one place on the planet. The natural forces of erosion, weather, tectonic plate action, and water have formed the earth’s physical features. Many US state and national parks attempt to preserve unique physical landscapes for the public to enjoy, such as Yellowstone, Yosemite, and the Grand Canyon.
Human geography is the study of human activity and its relationship to the earth’s surface. Human geographers examine the spatial distribution of human populations, religions, languages, ethnicities, political systems, economics, urban dynamics, and other components of human activity. They study patterns of interaction between human cultures and various environments and focus on the causes and consequences of human settlement and distribution over the landscape. While the economic and cultural aspects of humanity are primary focuses of human geography, these aspects cannot be understood without describing the landscape on which economic and cultural activities take place.
The cultural landscape is the term used to describe those parts of the earth’s surface that have been altered or created by humans. For example, the urban cultural landscape of a city may include buildings, streets, signs, parking lots, or vehicles, while the rural cultural landscape may include fields, orchards, fences, barns, or farmsteads. Cultural forces unique to a given place—such as religion, language, ethnicity, customs, or heritage—influence the cultural landscape of that place at a given time. The colors, sizes, and shapes of the cultural landscape usually symbolize some level of significance regarding societal norms. Spatial dynamics assist in identifying and evaluating cultural differences between places. RAS MAINS WORLD GEOGRAPHY
Traditionally, the field of cartography, or map making, has been a vital discipline for geographers. While cartography continues to be an extremely important part of geography, geographers also look at spatial (space) and temporal (time) relationships between many types of data, including physical landscape types, economies, and human activity. Geography also examines the relationships between and the processes of humans and their physical and cultural environments. Because maps are powerful graphic tools that allow us to illustrate relationships and processes at work in the world, cartography and geographic information systems have become important in modern sciences. Maps are the most common method of illustrating different spatial qualities, and geographers create and use maps to communicate spatial data about the earth’s surface.
Geospatial techniques are tools used by geographers to illustrate, manage, and manipulate spatial data. Cartography is the art and science of making maps, which illustrate data in a spatial form and are invaluable in understanding what is going on at a given place at a given time.
Making maps and verifying a location have become more exact with the development of the global positioning system (GPS). A GPS unit can receive signals from orbiting satellites and calculate an exact location in latitude and longitude, which is helpful for determining where one is located on the earth or for verifying a point on a map. GPS units are standard equipment for many transportation systems and have found their way into products such as cell phones, handheld computers, fish finders, and other mobile equipment. GPS technology is widely implemented in the transport of people, goods, and services around the world. RAS MAINS WORLD GEOGRAPHY
Remote sensing technology acquires data about the earth’s surface through aerial photographs taken from airplanes or images created from satellites orbiting the earth. Remotely sensed images allow geographers to identify, understand, or explain a particular landscape or determine the land use of a place. These images can serve as important components in the cartographic (map-making) process. These technologies provide the means to examine and analyze changes on the earth’s surface caused by natural or human forces. Google Earth is an excellent example of a computer tool that illustrates remotely sensed images of locations on the earth.