Protecting the Planet with Postgis: How we are calculating complex protected area coverage statistics for all countries in the world. — Miguel Torres
ProtectedPlanet.net is the online interface for the World Database on Protected Areas (WDPA), a joint project of IUCN and UNEP, and the most comprehensive global database on terrestrial and marine protected areas.
The WDPA is released every month and consists of a point and polygon dataset of over 210 000 entries. Over 91% of this data is in polygon format and the remaining 8% are points that can have an area as attribute.
Displaying protected area coverage statistics is one of the main features of this website. It is very important for the users to know what percentage of the territory is covered by protected areas in a given country, region or the entire planet. Previously, these statistics were calculated manually and every year a team spends several days calculating them for a report using ESRI Software.
We had a great challenge this time:
Can we automatically calculate the statistics every month for all the protected areas and countries in the entire planet?
In this case time matters: if we want to calculate statistics every month, it can't take 2 or 3 days of processing. To work through this, we chose a full open source solution with PostGIS to do all the back end tasks that we need to calculate statistics.
We were able to limit all this to 6 hours and we can now run automatically every month keeping coverage statistics up to date.