By Julia Cramwinckel
Global open geospatial products originating from Earth Observation (EO) and Volunteered Geographic Information (VGI) could potentially be used to measure the sustainable development goals (SDGs), in particular indicator 11.7.1: Average share of the built-up area of cities that is open space for public use. No research has yet focused on analysing the potential of these products for measuring this indicator, while they could provide a solution for data-poor countries. The objective of this thesis was therefore to investigate the role of open global geospatial data products in measuring SDG indicator 11.7.1. In order to do so, potential useful geospatial products were identified. These were used to measure the elements (the urban extent, the street space, and the public open spaces) of the indicator for the city Nairobi, following and building upon the official proposed methodology of the indicator. The results of the different products were compared against each other and against reference data originating from a public open space assessment performed by UN-Habitat and Nairobi County. Additional reference data for the street space was created using high resolution satellite imagery. The results showed that global open geospatial products can play a role. They can provide reflection upon the UN-proposed methodology, assist in the delimiting of public open spaces if EO and VGI products are combined, and outperform local datasets.