Mapping global urbanisation with satellite and social media in a revolutionary approach So2Sat is a pioneering European Research Council (ERC) project, led by Professor Xiaoxiang Zhu, using petabytes of data from Earth observational satellites and social media to create 3D/4D models of individual buildings on a global scale, in order to better understand the global urbanisation process. In the 20th Century alone, the global population has expanded from 1.65 billion to 6 billion and 50 years ago there were approximately half as many people in the world as there are today. A symptom of this exponential growth is worldwide urbanisation and spontaneously growing human settlements. Effectively tracking such amorphous developments globally was widely considered to be near impossible. City expansions, especially, are happening at pace, with migrations of people moving to urban areas. “Urbanisation is the second biggest important mega trend of global changes after climate change,” explains Professor
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Zhu. “If you look at the evolution of rural and urban population over time, there is actually a secret change of human history in 2008, when there were more people in the cities than in rural areas and if you look at the prediction for 2050, there are much more people who will eventually live in cities.” In 2050 we can expect three fourths of the population to be living in metropolises.
The challenges of urban expansion The evolution of very large cities can be chaotic, and how populations are distributed is not always known. For example, mega cities invariably include substantial informal
settlements such as slum areas with unknown numbers of people residing in them. These kinds of gaps in knowledge mean that sustainable planning for city planners and urban developers can be highly problematic. “Urban growth is mostly occurring in the developing areas: Africa, South America and Asia. Urbanisation, if not well controlled, will lead to informal settlements and slums. Without proper management this could endanger the lives of people who are living there. An example is in Mumbai, where in the past ten years more than fifty thousand fires happened in this city and about sixty seven percent of these fires are actually caused by faulty wiring. We need Geo-information.”
EU Research
