Earth Science: Geography

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Earth Science: Geography

Introduction

Many people think of geography simply as the study of maps and places. Although the science of geography requires understanding these things, the field is much broader than that. Geography is the study of Earth's surface and the way it affects people, the environment, politics, and other events or physical features.

The science of geography has three main branches: Physical geography is the study of Earth, its physical features, landforms, weather, soils, oceans, water, and attributes such as size and shape, both in the present and the past. Human geography is the study of people and their distribution, particularly with respect to culture, religion, politics, economics, health, demographics, and other characteristics. Environmental geography examines how people interact with the environment in relation to the space they occupy. Each branch overlaps the others in some ways, but differs in the kinds of questions it seeks to answer and in the focus of its work.

Historical Background and Scientific Foundations

As a science, geography relies heavily on the use of maps to show and explain the concepts it studies in the places they occur. Without maps, geographers would have a difficult time expressing and analyzing the data they collect. Cartography is the ancient art, and recent science, of mapmaking. People have used maps for thousands of years; the oldest ones known come from the Middle East, where the earliest civilizations began. One map of a Babylonian city shows hills, rivers or canals, and a specific plot of land with its size and owner labeled on it. Another ancient map from Turkey shows a city plan with individual buildings and roads, as well as a volcano. The advanced nature of these maps, showing both human-made and natural features in different scales, indicates that the idea of maps was not new when they were drawn. The Babylonians also produced a world map, showing a circular world surrounded by an ocean.

The Greeks and Romans were advanced cartographers. Ancient Greek geographers were interested in both physical and human geography, though those terms were not in use at the time. The poet Homer (fl. 8th or 9th century BC) was famous as a geographer for describing the shape of Earth as he knew it: land surrounded by sea. Later, Pythagoras (580–500 BC) advanced the idea that Earth was spherical; Aristotle (384–322 BC) verified this with experiments. The Roman historian Herodotus (c.484–c.430 BC) included a great deal of geographical information in his writing. His descriptions of places such as Egypt are so accurate that they have been used to guide archaeological expeditions. A famous passage from Herodotus speculates that the reason for the annual Nile River floods must be melting snow far upstream, although he was unsure where the snows fell since Africa is so hot. He was also interested in the people of the world and described their customs, though it should be noted that some of his work is based on observations and interviews, while other parts were mostly rumor and speculation.

One of the most important uses of maps in the ancient world was for travel. The Romans built an extensive network of roads that allowed armies and commerce to move through their huge empire. By the fifth century AD, a map known today as the Peutinger Table had been developed that showed a great number of roads with towns, cities, and inns along them. Remarkably, the map stretches from Ireland, Spain, and Morocco in the west to Sri Lanka and perhaps even China in the east. Though the dimension representing longitude is compressed, many features are easily recognizable even today. The original ancient map does not survive, but a medieval copy was discovered and published in the sixteenth century. The Romans were also skilled surveyors and made maps to plan colonies and towns. One of the largest city maps was of Rome, carved on marble by order of the Emperor Septimius Severus (AD 146–211). It showed the plans of temples and public buildings like theaters and even simple homes and apartment buildings.

The study of geography reached its most advanced state in the ancient world in the book Geography by Ptolemy (AD c.90–c.168), a Romanized Greek-Egyptian geographer. Ptolemy set out to record and update all the knowledge of the world that he was able to obtain. He stands out because he did not base his ideas on a philosophical ideal, but instead used data to shape his

conclusions. Ptolemy was the first to use a latitude and longitude grid to position features on his map, though its proportions were flawed since it was impossible for the Romans to measure longitude accurately. Ptolemy's work, lost or ignored for almost 1,000 years, was rediscovered in Europe during the late Middle Ages and provided a basis for the maps during the Renaissance and the age of exploration.

During the Middle Ages, the study of geography (and science in general) declined in Europe. However, people of other cultures at the time were studying Earth, using principles of geography to map and understand it. As early as the fifth century BC, the Chinese wrote about the geography of their empire. They described the physical characteristics of the land, rivers, lakes, and other features. They were also interested in agricultural crops, goods produced, and trades practiced in each particular area. Later, Chinese geographers drew maps with accurate scales and included geography as an important part of their imperial bureaucracy. Islamic geographers in the Middle East preserved the works of the Greek geographers and produced detailed works that included maps of the hajj, or yearly religious pilgrimage to Mecca.

The field of geography grew from cartography as scholars sought to understand more about the world and wanted to locate their data in specific places. In the nineteenth century, scientists such as the German Alexander von Humboldt (1769–1859) traveled widely to study the physical features of Earth, transforming the study of geography from a literary or philosophical pursuit to one of rigorous scientific inquiry. Humboldt insisted on using the scientific method and inductive reasoning to understand the phenomena he observed, including plants, weather, and agriculture.

The study of human geography was also taking shape at this time. German geographer Carl Ritter (1779–1859) is considered the father of the field. More of an academic than an explorer like Humboldt, Ritter concentrated his work on human habits and settlements. He was also concerned with how people used, changed, and adapted to particular areas, climates, or habitats. Humboldt, too, was interested in human geography, investigating rates of disease with respect to temperature.

Modern Cultural Connections

In the second half of the twentieth century, the study of geography became more systematic. Instead of simply collecting data, geographers began to analyze its meaning and connect it with other data and ideas. They also began to develop theories about the nature of their knowledge and to challenge themselves with new models and ways of thinking. Where their predecessors concentrated on facts and measurements, present-day geographers are concerned with the study of systems and the way individual factors influence one another. With these foundations, the modern study of geography has expanded into a vast field with numerous individual areas of study.

The study of geography is important because it helps us comprehend the world, its people, and the environment. At its most basic, physical geography is the knowledge of where things are located. It also attempts to understand what features are located in what

places, and in what relation to one another. Sometimes these features are not obvious to an uninformed observer. Beyond plotting the location and properties of mountains and rivers, physical geography also includes things that are important to our changing world and environment. Locations and frequency of wildfires; soil types and erosion rates; the sizes, locations, and effects of earthquakes; frequency and severity of floods, all of these topics and more are relevant to our lives, especially when viewed in the context of global climate change.

Human geography studies the distribution of people, their effect on the environment, and vice versa. It includes the physical presentation of social sciences such as economics, sociology, linguistics, politics, and demographics. Human geographers might examine how the environment influences disease in a community, for example, or why some people practice a traditional religion while others converted to a different faith. Cultural geography is a broad type of human geography that looks at many aspects of a culture, for example language, religion, food, and the economy, and how these things vary by location. Some human geographers are guided by philosophical principles; these include Marxist geographers who study the relationships between the perceived exploitation of workers and the places they inhabit, and feminist geographers who study gender equality based on location. All categories of human geography study people and how their lives are affected by the spaces they inhabit, although the focus of each subdiscipline may be very different.

The third branch, environmental geography, is the study of the way people use and perceive space in the natural world. It links physical and human geography because it deals with aspects of both disciplines. It is easy to understand how people might cut away hills for a highway or fill in coastal areas to create more land for building, but environmental geography addresses more than this. It is most heavily concerned with how human activity influences natural patterns like weather and water cycles. For example, an environmental geographer might be interested in a new water table forming under Las Vegas, where none had existed before the rapid population growth of the past 50 years. To understand how it developed, geographers would look at its physical location, extent, composition, and other characteristics. They would also study the population growth rate and the way that residents use water resources to determine how this influences the environment. Geographers would be equally interested in the ways that the physical environment in that location influences human behavior.

One of the most important developments in the field is the idea of “applied geography.” Going beyond research, applied geography uses science to solve problems. For example, determining past wildfire patterns might help predict future outbreaks, or the study of earthquake damage might reveal new techniques for construction or urban planning. Applied geography also helps explain the distribution of natural resources and how to manage them effectively.

From the development of the earliest maps to the most recent achievements, the science of geography will continue to influence the growth and development of the world's societies, environments, and people.

bibliography

Books

Gregory, Kenneth J. The Changing Nature of Physical Geography. New York: Oxford University Press, 2000.

Mitchell, Don. Cultural Geography: A Critical Introduction. Boston: Blackwell, 2000.

Periodicals

Pattison, William D. “The Four Traditions of Geography.” Journal of Geography 63, no. 5 (May 1964):211–216.

Web Sites

Newberry Library: The Hermon Dunlap Smith Center for the History of Cartography. “Cartographic Images of the World on the Eve of the Discoveries.” http://www.newberry.org/smith/slidesets/ss08.html (accessed November 13, 2007).

Valparaiso University. Department of Geography and Meteorology. “Von Humboldt and Ritter.” October 14, 1996. http://www.valpo.edu/geomet/geo/courses/geo466/topics/humboldt.html (accessed November 13, 2007).

René Nougayrède

Kenneth T. LaPensee

Scientific Thought: In Context