Where is Urban, Exactly?

What is urban and where is it? Seemingly so simple question, but it is not easy to define what exactly constitutes urban/rural and where we should draw the boundary between them.

At the 2017 CSI Meeting in Cali, Zhe Guo from IFPRI presented a study measuring urbanization trends between 1992 and 2013 in Africa and China using remote sensing imagery from six different sensors. For the cross-sensor calibration, curiously non-changing nighttime light of Sicily, Italy, was used.

Urban extents for major metropolitan areas measured using multiple sensors

Resulting analysis outputs showed unique spatio-temporal patterns of urban growth across major metropolitan areas across Africa and China. This study is being developed as a journal article, expected to be published in early 2018.

Learn more about the methodology and other geospatial work at IFPRI from Zhe’s presentation: Zhe Guo (IFPRI) 2017 – Center Update – CGIAR-CSI in Cali (Sep 22)