7 billion ‘extra’ trees have been discovered in Africa - part of the continent’s ongoing efforts to restore and reforest the land

Scientists have discovered billions of previously unrecorded trees in Africa, thanks to a collaboration between Google and the UN Food and Agriculture Organization (FAO).

Using an open-source tech tool called Collect Earth, a team of more than 350 African experts helped review, scan and analyze data from 88,000 sites across the continent. They examined land use and changes in that use over the past 20 years. One of their findings has been almost seven billion trees that, until now, hadn’t been counted.

The newly discovered trees are located outside of forests, and are distributed across an area equivalent to 537 million hectares. It wasn’t just trees that were discovered. The team concluded that there are more forests and more arable land than had been recorded in the past.

Collect Earth pulls in high-resolution satellite imagery and mapping data from Google Earth and Bing Maps. It can be used to check and validate existing maps, monitor land in rural and urban areas, collect data that can be used for socio-economic analysis and measure deforestation, reforestation and desertification.

Desertification has transformed an area called the Sahel in western and north-central Africa. Large tracts of fertile land have dried up and been assimilated into the nearby Sahara desert. Many African nations are on the front lines of climate-related upheavals like this and are taking steps to fight back.

In 2007, more than 20 African countries actively began working on an initiative called the Great Green Wall – a green belt of trees and forests stretching 8,000km from Senegal in the west, to Djibouti in the east.

“A decade in and roughly 15% underway, the initiative is already bringing life back to Africa’s degraded landscapes at an unprecedented scale,” the Great Green Wall website says.

As well as providing food security and jobs, the Wall “promises to be a compelling solution to the many urgent threats not only facing the African Continent, but the global community as a whole – notably climate change, drought, famine, conflict and migration,” it continues.

Reversing the deforestation trend could be one of the most effective ways to limit the harmful effects of climate change. Teaming up with organizations like the Tropical Forest Alliance and the One Trillion Trees movement, the World Economic Forum is working towards the creation of a series of global public-private partnerships made up of businesses, governments, civil society, indigenous people and international organizations.

The Collect Earth project’s name was the Africa Open DEAL, which stands for Data for Environment, Agriculture and Land. “Africa [is] the first continent to complete the collection of accurate, comprehensive, and harmonized digital land use and land-use change data,” the FAO says.

A team of more than 350 people with knowledge of the landscapes and land uses, gathered data using Collect Earth and then worked on in it a series of group sessions called Mapathons. These were run and organized by the Panafrican Agency of the Great Green Wall and the Southern Africa Development Community, along with the FAO.

The survey has assessed the Great Green Wall initiative to have 393 million hectares of land that could be planted and restored. It has also identified opportunities for agricultural land management that could deliver improved, sustainable yields.