Using geospatial data involves numerous uncertainties stemming from various sources such as inaccurate or erroneous measurements, inherent ambiguity of the described phenomena, or subjectivity of human interpretation. If the uncertain nature of the data is not represented, ill-informed interpretations and decisions can be the consequence. Accordingly, there has been significant research activity describing and visualizing uncertainty in data rather than ignoring it. Multiple typologies have been proposed to identify and quantify relevant types of uncertainty and a multitude of techniques to visualize uncertainty have been developed. However, the use of such techniques in practice is still rare because standardized methods and guidelines are few and largely untested. This contribution provides an introduction to the conceptualization and representation of uncertainty in geospatial data, focusing on strategies for the selection of suitable representation and visualization techniques.
Maps, just like text, paintings, and other media, are open to interpretation. Map interpretation describes the process of extracting meaning from a map to make sense of the real world. To arrive at an interpretation of the real world, an individual must reconcile their mental model of the world with that of the cartographer’s through the map. Because everyone has a different mental model of the world, a single map can connote a variety of meanings, and therefore, be interpreted differently. Cartographers can prime individuals to interpret a map in a particular way through selection, classification, symbolization, and other cartographic tools in the map design process. However, individual differences like beliefs and knowledge ultimately dictate the meaning someone forms from a map. Equally important to the formation of meaning is questioning the meaning of the map. Questioning the meaning considers why patterns or relations are a certain way and whether they should be trusted. Information is more contested than ever, so understanding a map is one thing, trusting it is another. In seeking out explanations for what is shown on a map, one can better understand the world around them.