Different Types of Isolines in Geography

Different Types of Isolines in Geography Topographic maps use a wide variety of symbols to represent human and physical features, including isolines, which are often used on maps to represent points of equal value. The Basics of Isolines and Contour Lines Isolines, also referred to as contour lines, can be used to represent elevation on a map by connecting points of equal elevation, for instance. These imaginary lines provide a good visual representation of  the terrain. As with all isolines, when contour lines lie close together, they represent a steep slope; lines far apart represent a gradual slope. But isolines can also be used to show other variables on a map besides terrain, and in other themes of study. For example, the first map of Paris used isolines to depict population distribution in that city, rather than physical geography. Maps using isolines and their variations have been used by astronomer Edmond Halley (of Halleys comet) and by doctor John Snow to better understand an 1854 cholera epidemic in England. This is a list of some common (as well as obscure) types of isolines used on maps to represent different features of the terrain, such as elevation and atmosphere,  distances, magnetism and other visual representations not easily shown on a two-dimensional depiction. The prefix iso- means equal. Isobar A line representing points of equal atmospheric pressure. Isobath A line representing points of equal depth under water. Isobathytherm A line representing depths of water with equal temperature. Isochasm A line representing points of equal recurrence of auroras. Isocheim A line representing points of equal mean winter temperature. Isochrone A line representing points of equal time-distance from a point, such as the transportation time from a particular point. Isodapane A line representing points of equal transport costs for products from production to markets. Isodose A line representing points of equal intensity of radiation. Isodrosotherm A line representing points of equal dew point. Isogeotherm A line representing points of equal mean temperature. Isogloss A line separating linguistic features. Isogonal A line representing points of equal magnetic declination. Isohaline A line representing points of equal salinity in the ocean. Isohel A line representing points receiving equal amounts of sunshine. Isohume A line representing points of equal humidity. Isohyet A line representing points of equal precipitation. Isoneph A line representing points of equal amounts of cloud cover. Isopectic A line representing points where ice begins to form at the same time each fall or winter. Isophene A line representing points where biological events occur at the same time, such as crops flowering. Isoplat A line representing points of equal acidity, as in acid precipitation. Isopleth A line representing points of equal numerical value, such as population. Isopor A line representing points of equal annual change in magnetic declination. Isostere A line representing points of equal atmospheric density. Isotac A line representing points where ice begins to melt at the same time each spring. Isotach A line representing points of equal wind speed. Isothere A line representing points of equal mean summer temperature. Isotherm A line representing points of equal temperature. Isotim A line representing points of equal transport costs from the source of a raw material.

The Asch Conformity Experiments and Social Pressure

The Asch Conformity Experiments and Social Pressure The Asch Conformity Experiments, conducted by psychologist Solomon Asch in the 1950s, demonstrated the power of conformity in groups and showed that even simple objective facts cannot withstand the distorting pressure of group influence. The Experiment In the experiments, groups of male university students were asked to participate in a perception test. In reality, all but one of the participants were confederates (collaborators with the experimenter who only pretended to be participants). The study was about how the remaining student would react to the behavior of the other participants. The participants of the experiment (the subject as well as the confederates) were seated in a classroom and were presented with a card with a simple vertical black line drawn on it. Then, they were given a second card with three lines of varying length labeled A, B, and C. One line on the second card was the same length as that on the first, and the other two lines were obviously longer and shorter. Participants were asked to state out loud in front of each other which line, A, B, or C, matched the length of the line on the first card. In each experimental case, the confederates answered first, and the real participant was seated so that he would answer last. In some cases, the confederates answered correctly, while in others, the answered incorrectly. Aschs goal was to see if the real participant would be pressured to answer incorrectly in the instances when the Confederates did so, or whether their belief in their own perception and correctness would outweigh the social pressure provided by the responses of the other group members. Results Asch found that one-third of real participants gave the same wrong answers as the Confederates at least half the time. Forty percent gave some wrong answers, and only one-fourth gave correct answers in defiance of the pressure to conform to the wrong answers provided by the group. In interviews he conducted following the trials, Asch found that those that answered incorrectly, in conformance with the group, believed that the answers given by the Confederates were correct, some thought that they were suffering a lapse in perception for originally thinking an answer that differed from the group, while others admitted that they knew that they had the correct answer, but conformed to the incorrect answer because they didnt want to break from the majority. The Asch experiments have been repeated many times over the years with students and non-students, old and young, and in groups of different sizes and different settings. The results are consistently the same with one-third to one-half of the participants making a judgment contrary to fact, yet in conformity with the group, demonstrating the strong power of social influences. Connection to Sociology The results of Aschs experiment resonate with what we know to be true about the nature of social forces and norms in our lives. The behavior and expectations of others shape how we think and act on a daily basis because what we observe among others teaches us what is normal, and expected of us. The results of the study also raise interesting questions and concerns about how knowledge is constructed and disseminated, and how we can address social problems that stem from conformity, among others. Updated  by Nicki Lisa Cole, Ph.D.