Building a Crowd-Sourcing Tool for the Validation of Urban Extent and Gridded Population

  • Steffen Fritz
  • Linda See
  • Ian McCallum
  • Christian Schill
  • Christoph Perger
  • Michael Obersteiner
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6783)


This paper provides an overview of the crowd-sourcing tool Geo-Wiki, which is used to collect in-situ land cover validation data from the public. This tool is now being modularized in order to allow for domain specific land cover validation. Agriculture and biomass versions of Geo-Wiki are already operational. The next module, which is called, is aimed at the validation of urban extent and gridded population data. The aim of this paper is to outline the structure of this module and the datasets that will aid in the validation of this land cover type and gridded population data. The ultimate aim of Geo-Wiki is to produce a hybrid land cover map that is better than existing products, including estimates of urban extent.


Crowd-sourcing urban areas land cover validation Google Earth 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Steffen Fritz
    • 1
  • Linda See
    • 1
  • Ian McCallum
    • 1
  • Christian Schill
    • 1
    • 2
  • Christoph Perger
    • 3
  • Michael Obersteiner
    • 1
  1. 1.International Institute for Applied Systems Analysis (IIASA)LaxenburgAustria
  2. 2.University of FreiburgFreiburgGermany
  3. 3.Fachhochschule Wiener NeustadtWiener NeustadtAustria

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