Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60Glossary of geographic terms 49 A aerial photograph: a photograph of part of the Earth’s surface usually taken from an airplane aquifer: an underground permeable rock layer within which water is stored and can flow, and from which water can be extracted for use at the surface arable land: an area suitable for growing crops artifacts: the material manifestations of a culture such as tools, clothing, and foods atlas*: a book of maps or charts B bedrock: the solid rock underlying unconsolidated (loose) surface materials. General types of bedrock include igneous rock, metamorphic rock, and sedimentary rock (see separate glossary entries for each of these). biodiversity: biological diversity in an environment as indicated by numbers of different species of plants and animals border*: a line separating two political or geographic areas, especially countries (e.g., Germany’s western border with France) or states (e.g., Indiana’s northern border with Michigan) boundary: a line marking the limit or extent within which a system exists or functions, including a social group, a neighborhood, a state, or physical feature C cardinal directions: the four main points of the compass: north, east, south, and west cartography: the study of making maps census: an official count of a population conducted by a government. Typically records trends among individuals and groups in the population choropleth map*: shows differences between areas by using colors or shading to represent distinct categories of qualities (such as vegetation type) or quantities (such as the high school graduation rate, population density, or birthrate) climate: long-term trends in weather and atmospheric conditions climate variability: changes in the patterns of weather and climate at both temporal and spatial scales climograph: a graphical depiction of average monthly temperatures and precipitation amounts for a particular location continental divide*: an area of high ground on each side of which water flows into a different ocean or sea, or flows into an internally draining basin contour map: a representation of some part of the Earth’s surface using lines along which all points are of equal elevation culture: learned behavior of people, which includes their belief systems and languages, their social relationships, their institutions and organizations, and their material goods (e.g., food, clothing, buildings, tools, machines) D data classification*: grouping similar data in order to more easily identify patterns. Different methods exist for grouping quantitative data (e.g., equal interval, quantile, natural breaks). Most quantitative maps in this Atlas have been classified using natural breaks, a method that looks for natural groups inherent in the data and maximizes differences between classes. demography: the study of population statistics, changes, and trends based on various measures of fertility (adding to a population), mortality (subtracting from a population), and migration (redistribution of a population) Definitions reproduced with permission from the National Geography Standards, 2nd edition (Heffron and Downs 2012) with minor modifications made to ensure consistency and improve readability. Entries denoted by * indicate terms acquired from alternate sources.