Geo-Wiki Global Built-up Surface Validation Campaign

Aim of the Campaign

The Global Built-up Surface Validation campaign aims to collect valuable information on built-up surfaces. There is a great deal of interest in mapping built-up surfaces because of urban expansion and the impacts related to soil degradation, increased flooding risk and biodiversity.

Built-up surfaces are defined as areas where buildings can be found. Buildings are defined as enclosed constructions above ground, which are intended or used for the shelter of humans, animals, things or for the production of economic goods and that refer to any structure constructed or erected on its site.

In this campaign, we will collect information on built-up surfaces at around 50,000 unique locations, where each location will be visited by 5 different participants during the campaign.

This information will help IIASA and the Joint Research Centre of the European Commission (JRC) to validate their Global Human Settlement Layer (GHSL), which consists of current and past built-up surface layers. The JRC has developed a series of atlases based on these layers, which can be found here.

In addition to identifying built-up areas during the campaign, we will also ask you to look for change in built-up features between the Google Maps and Microsoft Bing images, since satellite imagery in Google Maps is often more recent than Bing. This will help us to quantify how much change is happening in urban areas.

Join our campaign, contribute to scientific research on validating the GHSL, and help us to meet our goal!

Prizes

We would like to reward our citizen scientists with prizes! The campaign's top 30 participants who contribute the most data (measured by both quality and quantity) will win prizes based on their place on the leaderboard as follows:

• The top 11 contributors on the leaderboard will be offered:
  • o An Amazon voucher (valued from 175 to 500 Euros) AND co-authorship on a peer-reviewed scientific journal paper summarizing and making openly available the information collected.
• Contributors ranking between 12 and 25 on the leaderboard will be offered a choice of:
  • o An Amazon voucher of 100 to 150 Euros, OR, alternatively,
  • o Co-authorship on a scientific paper.
• Contributors ranking between 26 and 30 on the leaderboard will be offered an Amazon voucher ranging between 50 to 75 Euros.

Please note:

• Working in groups using one user account is forbidden.
• To receive any of the prizes mentioned above, your relative quality score should exceed a certain threshold. We will determine this threshold during the campaign based on patterns in performance and the quality of the imagery. This is to ensure that we are as fair as possible while maintaining a minimum level of quality. However, we require a minimum of 2000 validations to qualify for a prize.
• If you disagree with a control classification, please send us an email with the reasons why. If this is our mistake, we will adjust your score, removing any penalties and applying the correct points to your overall score.

Please contact us for further information and enquiries.