Keywords: Time-distance visualization, Distance cartogram, Travel time, Cognitive distance, Distance perception
Abstract. Traditional maps are often direct visualizations of the Euclidean distances in space. As the concepts of time and distance are intrinsically intertwined in the human cognitive systems for environmental perception, the mapping of a unity of time and distance is thus either intuitive or convenient in many occasions. This paper presents three examples to demonstrate the value of visualizing time-distance instead of the physical Euclidean distance in contemporary mapping. The first example maps travel time as perceived distance in an urban environment. Visualizations of the time-space reflecting modern high-speed travel behaviours make it convenient to detect patterns and identify anomalies that matter for the functions in such space. The second example concerns trail mapping in a remote rainforest, where hand-drawn maps reflecting travel effort are more desirable than accurate GIS maps for local navigation and trail hiking purposes. The last example shows that traditional maps are ineffective in communicating hurricane flooding risks since the conventional spatial model based on surficial distance does not reflect non-surficial spatiotemporal dynamics for realistic representations of the risk space. While the Euclidean distance on the physical earth surface is what traditional maps chart and what our modern spatial thinking has been accustomed to, these examples show that such distance is limited in portraying many aspects of our perceived and experienced dynamic distances that affect our living. The adoption of spatial representations such as time-distance maps breaks the mental set accustomed to the traditional distance maps and is worth considering in many occasions.