21 June 2018: The Joint Research Centre (JRC) of the European Commission has published a follow-up edition of the ‘World Atlas of Desertification.’ It aims to provide “the first comprehensive, evidence-based assessment of land degradation at a global level,” to highlight the urgency of adopting corrective measures and to offer decision makers a tool for improving local responses to soil loss and land degradation. The previous edition of the Atlas was published two decades prior.

Unlike the first two Atlases, the third World Atlas on Desertification (WAD3) does not attempt to present a comprehensive global model of desertification, but aims to shed light on the complex human-driven interactions among social, economic and environmental systems that contribute to land degradation. Building on diverse sources of scientific data and socio-economic analysis undertaken over the past two decades, WAD3 aims to serve as a decision making tool through which policy makers and practitioners can pursue solutions for land degradation challenges at different scales.

The analysis of global land degradation trends is organized under five key themes: global patterns of human domination; feeding a growing global population; limits to sustainability; convergence of evidence; and solutions.

Assessing the evidence

Summarizing the evidence so far, as contained in the Thematic Assessment of Land Degradation and Restoration of the Intergovernmental Science Policy Platform on Biodiversity and Ecosystem Services (IPBES), the JRC notes that, inter alia, over 75% of the Earth’s land area is already degraded, and over 90% could become degraded by 2050. Globally and on an annual basis, a total area half of the size of the European Union (4.18 million km²) is degraded, with Africa and Asia most affected. The data estimate the economic cost of soil degradation in the European Union to be in the order of tens of billions of euros every year. Regarding agriculture, the findings show how land degradation and climate change could lead to a reduction of global crop yields by approximately 10% by 2050, largely in India, China and sub-Saharan Africa, where land degradation could halve crop production. On migration, per the publication, issues linked to scarce land resources could displace an estimated 700 million people, by 2050. The figure could reach up to 10 billion by the end of this century.

Reflecting on land degradation trends over the past two decades, the Atlas highlights a number of key messages, including the “alarming urgency” of some recurring global issues, such as surface and ground water, as well as the growing importance of issues “that were only suspected previously” – such as the role of smallholder farmers – in shaping both processes and solutions. Furthermore, the Atlas “reconfirms” some regional patterns of potential degradation in areas such as south Asia China, while revealing new regional patterns of potential land degradation, especially in central Asia. The Atlas notes that these region-specific insights raise concerns about the world’s ability to meet the demands of future populations through maintaining and increasing yields on high-density croplands, while closing yield gaps with low-density and low-input croplands.

The Atlas also highlights complementary strategies that can help avert further land degradation, including more sustainable consumption and production, shifting to plant-based diets, consuming animal proteins from sustainable sources and reducing food loss and waste.

Using the Atlas

WAD3 builds on new data processing methods, including the linking of thousands of high-performance computers, as well as 1.8 petabytes of satellite data. The volume of data generated is equated to “2.7 million CD-ROM discs or more than six years of 24/7 full, high definition video recording.” This information is used to derive a set of global “convergence of evidence” maps covering 14 variables associated with land degradation that can be combined or overlaid to help identify patterns of convergence that may signal potential stress on land resources. The maps replace desertification maps contained in previous editions of the Atlas.

The accompanying WAD3 web platform aims to facilitate this user-driven approach by providing access to global data sets that can be further analysed to help identify areas where degradation might be expected within a specific locality or region of interest. The web platform is designed to support users to validate or discard findings by comparing them with more geographically specific local data. The platform further aims to support comparisons of results with similar sites in other parts of the world, and to help determine conditions under which solutions that have been applied elsewhere could be applied or adapted to the local context.

Previous editions of the Atlas were published in 1992, ahead of the Earth Summit in Rio de Janeiro, with a follow up edition in 1998 containing additional case studies. Under the Sustainable Development Goal on life on land (SDG 15), target 15.3 calls on the global community to “combat desertification, restore degraded land and soil, including land affected by desertification, drought and floods, and strive to achieve a land degradation-neutral world,” by 2030. [UNCCD Press Release] [JRC Press Release] [Publication: World Atlas of Desertification] [Publication: IPBES Thematic Assessment of Land Degradation and Restoration – Summary for Policy Makers]

This story has been amended to focus on the information contained in the Atlas. The original press release for the Atlas included information from additional sources.