Google Earth Engine comes to South Africa

By Glenn Moncrieff, Data Scientist, SAEON Fynbos Node Tweet

The data collected by Earth observing satellites has revolutionised the way we monitor the planet.

Every day new images are acquired that help document changes in ocean currents, global atmospheric circulation and the productivity of plants.

New satellites such as Sentinel 2 operated by the European Space Agency, or Landsat 8 operated by NASA, have opened up a new realm of possibilities by making their data freely available to the public.

But the vast amount of data they provide poses a challenge to scientists trying to use this information. Most researchers do not have at their disposal the many terabytes (1 000 gigabytes) of storage required or massive computer processing power.

To overcome these issues, and democratise the power of satellite remote sensing, Google invented a tool called Google Earth Engine that combines satellite imagery with planetary-scale analysis capabilities, making it possible for scientists, researchers and developers to detect changes, map trends and quantify differences on the Earth's surface. Google Earth Engine [https://earthengine.google.com] is a free Google product supported by the Google Earth Outreach programme.

When using Google Earth Engine, researchers perform all their analysis on data hosted on Google's servers, and only view or download the results they need. The raw data never has to be housed on their own computers, nor do their local machines need to do any of the processing.

New satellites such as Sentinel 2 operated by the European Space Agency have opened up a new realm of possibilities by making their data freely available to the public (Picture: ESA) Dr David Gibson of Google demonstrates the use of Google Earth Engine to workshop participants at Stellenbosch University

South African workshop

SAEON scientists Jasper Slingsby and Glenn Moncrieff helped to organise South Africa's first-ever workshop on Google Earth Engine. The two-day course, presented by Dr David Gibson of Google and Dr Madhu Mysore from the Nature Conservation Foundation in India, was held from 25–26 June. It was hosted by the Department of Geography and Environmental Studies at Stellenbosch University.

Organised in conjunction with Rhodes University and funded through the SAEON RReTool (Rapid and repeatable tools for monitoring and mitigating global change impacts on natural resources) project, the workshop brought together over 50 researchers from universities and research institutions around Southern Africa to learn more about Google Earth Engine.

Alta de Vos, a senior lecturer at the Department of Environmental Science at Rhodes University and one of the key organisers of the workshop said, “The real advantage of Google Earth Engine is that you can run analyses that used to require extensive hardware and expensive software on a regular PC. Whilst virtually anyone can access Google Earth Engine, some technical skill is required to use it productively. This workshop is an attempt to develop some of these technical skills among scientists and practitioners who can put Google Earth Engine to work to understand and solve real-world problems. We also wanted to build connections between people who use Google Earth Engine locally.”

After two days of instruction and hands-on experience, participants presented the results of a 'buildathon' – mini-projects completed in just a few hours. The true power of Google Earth Engine was on display as great results on projects such as 'Classifying Prosopis in the Northern Cape province' and 'Fire mapping across Africa' were achieved in a very short period of time.

Participants left feeling empowered to go forward and continue using Google Earth Engine in their own work. Many expressed their interest in, and anticipation of the next event that will bring users of Google Earth Engine in Africa together.