This has been, so far, the most intense shriveling movement in transport history, when the maximum available speed raised from 700 km/h with jets to the supersonic speed of Concorde.
Considering, in a simplified model, terrestrial speed of 100 km/h, say on a motorway or by train, the slope of cones takes this geometry. During this Concorde period, terrestrial speed was 15 times slower than the maximum available speed.
This image is very close to the idea of the chestnut that I announced in 2007. High quality image download link.
Unlike all previous time-space relief representations (1997, 2009) where the surface is based on the edges of a graph, in the representations developed in 2016, we introduce conic shapes to represent time-space. The cone is the basic structure of this representation. Cones are characterized by a slope that follows the ratio between the speed of basic terrestrial networks, i.e. the road system, and the maximum available speed, which is attained, on the period we consider, through the air transport system.
On the figure we have two cities joined by a fast non-stop transport system, and also by a slower terrestrial transport mode. The fast transport link is represented through a red straight line, while the cones represent the surface on which slower terrestrial transport mode are drawn. Assuming that travel speed are similar in all the geographic space considered, the slope of the cones centered on the two cities is a coherent representation of time-space. The two cones intersect midway between the two cities. The slope of the cones implies that the length of the straight red line, and of the line drawn on the cone and joining the two cities, are proportional to the respective transport time. This forms a time space representation with different transport speed, and a time-space scale can be added, as in the USA map (p. 8).
Very excited when I first saw it on my computer screen. This is the first time this image, which I had in mind for years, finally materializes.
Unfortunately it has proven very difficult, for me at least, to control cones geometry. In addition in Cesium it is not possible to draw geometries under the surface of the globe. the problem is that, conceptually, the time-space relief map model, everything occurs under the surface.
An exchange with Cesium developers has indicated an alternative choice: the library three.js, which has less limitations for our purpose.
Time space relief cartography was invented in 1993 to map the time-space contraction assuming the coexistence of fast and slow transport modes. Initially applied locally to terrestrial modes (1993 p. 41), the principle has been applied to urban spaces (1997 p. 209 and 235) continental scales (1994 p. 253) and to the air mode (2009). The next major step, an ongoing work, is to create a cartographic representation of the earth, the global time-space.
At that time the model is not finished as illustrated by the incomplete bottom of facets. A triangle is missing but all the networks are visible, since they form the structure on which the relief is drawn. Relief comes as a surface along the deformed road network. Three terrestrial transport modes are represented here: classic road, motorway (mode 6) and high-speed rail (mode 3).
By lack of available color printer in the CESA laboratory, analog photo of computer screen was one of the few possible options to realize this cartography. Later we used print-screen software to produce bitmap images, and even later developed the software MapNod to produce direct vectorial images in the WMF format.