Accounting of Transportation Networks
Frequent image captures combined with high resolution imagery make it possible to monitor the progress of infrastructure projects, road traffic and structure integrity. Satellite imagery and analysis techniques can provide the underlying data to inform infrastructure investments. As next-generation Earth imaging satellites such as Maxar’s Worldview Legion proliferate, daily updates on infrastructure and its uses will become possible. In countries lacking regional road maps, imagery can offer a relatively cheap base layer from which to map rural road networks. The images below explore the suitability of imagery at various resolutions for identifying road features, which exemplifies the necessary compromise between detail and acquisition cost. The highest-resolution commercial imagery regularly offered (0.3 meters per pixel) allows for the detection of narrow, unpaved footpaths. These become invisible at 1.5 meters, at which the gridded residential roads are the smallest observable feature. This grid remains recognizable at 2.5 meters but is more likely to become with the surrounding vegetation. At 5-meter resolution, even the relatively large secondary road which cuts through the neighborhood becomes difficult to distinguish reliably, making the single primary road that travels the length of Palawan the only visible linear feature.